Microbial fertilizer regulates C:N:P stoichiometry and alleviates phosphorus limitation in flue-cured tobacco planting soil

Microbial fertilizer regulates C:N:P stoichiometry and alleviates phosphorus limitation in flue-cured tobacco planting soil | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Help Center Sign In Submit a Preprint Cite Share Download PDF Article Microbial fertilizer regulates C:N:P stoichiometry and alleviates phosphorus limitation in flue-cured tobacco planting soil Junna Feng, Lulu Chen, Tiyuan Xia, Yanan Ruan, Xiaolu Sun, Tian Wu, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-2145253/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 24 Jun, 2023 Read the published version in Scientific Reports → Version 1 posted 9 You are reading this latest preprint version Abstract By studying the response of soil and microbial biomass stoichiometric characteristics to fertilization, it is possible to optimize effective fertilization management during flue-cured tobacco growing periods. In this study, we studied the effect of compound fertilizers combined with microbial fertilizer treatments on stoichiometric characteristics of rhizosphere soil and the limitation of microbial resources during the flue-cured tobacco growth periods. The results indicated that soil and microbial C:N:P varied greatly with the growing period, the effect of sampling time was usually greater than fertilization treatment, and the microbial C: N:P did not vary with the soil resource stoichiometric ratios. With the extension of the growth period, the microbial metabolism of tobacco-growing soil was limited by phosphorus and showed a trend of increasing first and then decreasing. The rhizosphere soil microbial resources nitrogen and phosphorus limitation were mainly affected by soil water content, soil pH, microbial biomass carbon, and the ratio of microbial biomass carbon to microbial biomass phosphorus, and the application of microbial fertilizers can reduce phosphorus limitation. Therefore, the application of microbial fertilizers regulates the limitation of microbial resources by affecting the soil and microbial biomass C: N: P in flue-cured tobacco rhizosphere soils. Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction In the global biogeochemical cycle, carbon (C), nitrogen (N) and phosphorus (P) play pivotal roles in plant growth and soil fertility, and their interactions are closely intertwined through a series of physical, chemical, and biological processes 1 , 2 . Ecological stoichiometry provides an extremely effective and integrated approach to studying this coupling and knowing the changes in element ratios 3 . The ecological stoichiometric ratio of C, N, and P can reflect the relationship between soil, microorganisms, and enzymes, and have been widely used in the study of nutrient supply and demand balance in different ecosystems 4 – 7 . Soil C:N:P stoichiometry is a functional trait that reflects nutrient use efficiency and nutrient limitation 8 , and can maintain ecosystem functions against global change 9 . In plant-soil systems, the C:N:P ratio regulates microbial community composition and maintains a balance between element uptake and release. The decomposition of soil organic matter is controlled by soil microbes, which affects the balance of carbon, nitrogen, and phosphorus in the ecosystem 10 . The microbial C:N:P ratio determines the direction of microbial activity and the release of organic nutrients 11 . Soil C, N, and P availability generally limit the metabolism of microorganisms 12 – 14 . When soil microbial resources are limited, plant-microbe competition for nutrients increases, posing a threat to plant colonization and growth 15 , 16 . Therefore, It is important to know the relationship between soil C:N:P ratio and soil microbial C:N:P ratio to understand soil microbial nutrient limitations 17 . Additionally, the enzyme stoichiometric ratio can reflect the metabolic function of the microbial community and the biological cycle of nutrients in the environment 18 , 19 . As an indicator of the carbon, nitrogen, and phosphorus requirements of soil microorganisms, the enzyme stoichiometric ratio can also be calculated 20 , 21 . We believe that it is the result of the interaction of various microorganisms with other factors (including temperature, moisture, nitrogen, phosphorus, and crop roots), which indirectly reflects the availability of soil resources 22 , 23 . It is an effective indicator for evaluating the limit of soil microbial resources 12 – 14 . Currently, the most commonly used method to characterize soil microbial resource limitations is the ratio of carbon, nitrogen, and phosphorus-related enzyme activities, enzyme stoichiometric vector analysis (vector length and vector angle), and threshold elements ratios (TERC:N and TERC:P) 2 , 7 , 24 . Patterns of soil resource limitation in cultivated land based on enzyme stoichiometry have been reported in different regions. For instance, Cui et al. 2 reported that the C:N:P ratio of microbial enzyme activities, vector angle, threshold elements C:N, and C:P ratios for farmland in Jilin Province, China, arguing that microbial metabolism was mainly nitrogen-limited under organic fertilizer treatments. Wang et al. 24 observed that the combined application of organic and chemical fertilizers could reduce soil carbon limitation in tobacco planting soils in Yunnan based on the study of vector length and angle. Furthermore, some evidence suggests that there may be a dynamic equilibrium relationship between the stoichiometric ratio of soil extracellular enzymes and the stoichiometric ratio of soil and microorganisms 25 . In areas with relatively restricted environments, the stoichiometric ratio of enzymes remains relatively stable, and microorganisms need to maintain the relative balance between acquisition and investment of various elements to better cope with nutrient deficiencies and maintain soil nutrient dynamic equilibrium 26 . Yin et al. 4 studied the stoichiometric characteristics of C, N, and P in soil microbial extracellular enzymes in Northeast China, and found that extracellular enzyme N:P was significantly negatively correlated with soil N:P; a significant positive correlation between extracellular enzyme C:N and microbial C:N. Therefore, an integrated analysis of C, N, P stoichiometric characteristics of soil resources, and microbial and enzymatic activities is necessary for the study of ecological chemometrics. Fertilizer application is a key agricultural practice to maintain or improve the fertility of agricultural soils. The nutrient content of farmland soil changes with fertilization. These changes alter the soil C, N, and P stoichiometry, and greatly affect the C, N, and P of soil enzyme activities and microbial biomass 27 , 28 , 13 . The imbalance between soil microbial demand and soil substrate supply can affect C, N, and P nutrient cycling 9 . Typically, N is a key nutrient limiting the net primary productivity of agroecosystems 29 , and fertilizer application reduce N availability by increasing soil carbon fixation. For instance, Shen et al. 5 observed that replacing 20% or 50% of chemical fertilizers combined with organic fertilizers will aggravate soil microbial nitrogen limitation in greenhouse soils for vegetable cultivation 5 . In arid and semi-arid regions, organic fertilizers alone or in combination with nitrogen fertilizers can aggravate nitrogen limitation 6 . Recent studies have shown that phosphorus limitation is common in agroecology 30 , 31 , and the application of organic nitrogen to replace chemical fertilizer nitrogen application is beneficial to relieve soil microbial carbon limitation and phosphorus limitation 32 . Tobacco is an important economic crop in Yunnan Province, and the yield and quality were affected by many factors including the climate, fertilization management, crop rotation pattern, soil properties, and soil microorganisms 33 – 35 . Previous studies on the C, N, and P stoichiometry were used to reflect flue-cured tobacco soil fertility levels 36 . However, to our knowledge, only a few studies have elucidated the effects of different fertilization treatments on the limitation of microbial resources in tobacco-growing soils in recent years 13 , 24 . On the other hand, many studies have confirmed that microbial fertilizers instead of chemical fertilizers can promote the absorption and transformation of soil available nutrients while reducing environmental pollution, and improving soil fertility 37 . However, there are few studies on the effect of microbial fertilizer application on microbial resource limitation. Therefore, from the perspective of rational fertilization and improvement of soil fertility, it is very important to study the changes in soil microbial resource limitation under different fertilization strategies. Finally, the ecological stoichiometric properties of soil C, N, and P in different ecosystems were significantly affected by the sampling period. Qi et al. 7 indicated that soil and microbial-related properties and their C:N:P ratios were more influenced by the sampling stage than by the forest type. Jin et al. 38 showed that the C, N, and P ratio of paddy soil was significantly higher in the jointing period than that in the mature period. These studies demonstrated that it is beneficial to determine the stoichiometric characteristics of C, N, and P in different sampling periods to reflect the soil nutrient requirements more accurately and to know the changes of plant elements in different growth periods. In this study, we investigated the relationship between soil, microbial, and enzyme activity C, N, and P stoichiometry during the tobacco growing season and the response of microbial resource limitation to microbial fertilizer application, we intend to address the following two questions: 1) Does microbial fertilizer application lead to changes in a stoichiometric ratio of soil and microbial biomass C, N, P, compared to conventional fertilizer application? 2) What factors influence the limitation of microbial resources in tobacco-planted soils? Materials And Methods Ethics statement. The authors promise that all the methods were performed in accordance with relevant guidelines and regulations. Study area, experiment design, and soil sampling. The experiment site is located at the new flue-cured tobacco technology test base of Ganlanpo, in Mile, Hani-Yi Autonomous Prefecture of Honghe, Yunnan, China (103°27′E; 24°23′N, elevation 1451 m). The average annual rainfall, temperature and sunshine hours were 990.4 mm, 18.8°C, and 2131.4 h, respectively. The soil type is red soil and the previous crop is wheat. The major soil properties of the field before transplanting were as follows: pH of 6.09, the contents of soil organic carbon (SOC), soil total nitrogen (TN), soil total phosphorus (TP) and total potassium were 15.20, 1.34, 1.03, and 5.37 g/kg, and the contents of soil alkali-hydrolyzed nitrogen, available potassium and available phosphorus were 121.87, 14.76 and 193.41 mg/kg. This experiment was randomly distributed, with four treatments and three replicates: conventional fertilization (CK); conventional fertilization + microbial fertilizer (T1); 75% conventional fertilization + microbial fertilizer (T2), and microbial fertilizer alone (T3). Among them, the conventional fertilization is humic acid organic-inorganic compound fertilizer 50g/plant (N + P 2 O 5 + K 2 O ≥ 33%, 8-5-20) and the microbial fertilizer 80 g/plant (CociCoLi, which was produced by Wuhan Kenuo Biotechnology Co., Ltd., the number of effective viable bacteria is more than 200 million/g, organic matter ≥ 60%, humic acid ≥ 10%). The microbial fertilizer was used as base dressing before transplanting and the compound fertilizer was fertilized by annularity fertilizing when transplanting. The test variety was the local main variety, K326, the use of base and top-dressing fertilizer, picking, and backing were set up in line with local management methods 35 . The row spacing of tobacco plants is 1.2m×0.55m, 1000 plants/acre, and each treatment plot has 60 tobacco plants, about a total of 40 m 2 (excluding the protected lines). The rhizosphere soil samples were collected according to the method of Wang et al. 34 during the root extending period (6–8 leaves), flourishing period (13–14 leaves), mature period (3–5 days before harvesting), and harvest period, and named in the order of R, F, M, H. The collected soil samples were mixed according to the same treatment, sieved after removing impurities, stored in a sealed bag, and transported back to the laboratory for preservation within 24 hours. Each sample was divided into two parts, one naturally dried for the determination of basic physicochemical properties of the soil and the other stored at -20°C for the determination of soil microbial properties. Determination of soil physical, chemical, and microbial properties. The soil water content (SWC) was calculated by the amount of loss after dried 48 h by using the method of NY/T1121.3-2006. Soil pH was measured in water (1:2.5 w/v) according to NY/T1377-2007 by using a pH meter (PHS-3C). The SOC, TN, and TP contents were measured according to HJ 695–2014, NY/T 53-1987, and NY/T 88-1988, respectively. The soil microbial biomass contents of carbon, nitrogen, and phosphorus (MBC, MBN, and MBP) were measured according to the chloroform-fumigation-extraction method 39 , and a conversion factor E of microbial biomass carbon, nitrogen, and phosphorus was 0.38, 0.57, 040, respectively 40 – 43 . We also calculated a range of soil and microbial ratios, such as SOC/TN (sC/N), SOC/TP (sC/P), TN/TP (sN/P), MBC/MBN (mC/N), MBC/MBP (mC/P) and MBN/MBP (mN/P) in this study. The activities of four common C, N, and P-related hydrolytic enzymes includingβ-1,4-glucosidase (BG), β-1,4-N-acetyl-glucosaminidase (NAG), leucine aminopeptidase (LAP), and acid phosphatase (ACP) were measured in this study. The activities of BG and NAG were determined according to the previously described method 44 . The LAP and ACP activities were measured using a physiological assay kit (Suzhou Keming Biological Technology Co., Ltd., Suzhou, China) according to the manual. Like many other studies, BG, (NAG + LAP) and ACP were used to be C-acquire enzyme activities(C-acq), N-acquire enzyme activities (N-acq), and P-acquire enzyme activities (P-acq) 13 . On the other hand, we calculated the stoichiometric ratios of C, N, P microbial enzyme activity, including BG to (NAG + LAP) (eC/N), BG to ACP (eC/P), and (NAG + LAP) to ACP (eN/P) 13 . We also calculated the specific enzyme activity per unit of microbial biomass, like BG/MBC (C-acq/MBC), (NAG + LAP)/MBN (N-acq/MBN), and ACP/MBP (P-acq/MBP) to represent microbial enzyme activity coefficient 24 . Finally, we calculated the vector angle, and the ratio of C, N, and P enzyme activity to characterize the enzyme stoichiometry 45 , and we calculated the microbial stoichiometric homeostasis 7 , 46 , 47 . Statistical Analysis. A permutation multivariate analysis of variance (PERMANOVA) was conducted to determine the effect and significance of sampling time and fertilization treatments and their interactions on soil indicators by using the "vegan" package of R 48 . In this study, the "Shapiro.test" and "Levene-test" were used to perform the normal distribution test and homogeneity of variance test. The logarithmic or reciprocal transformation was carried out for the indicators that did not conform to the normal distribution. For the indicators that failed converted, the significance of differences between groups was used in the nonparametric test (Kruskal-Wallis). one-way analysis of variance (ANOVA) and Tukey's " honestly significant difference" (HSD) test were used to determine whether differences in soil basic physical and chemical properties, soil, microbial, and related enzyme C, N, P stoichiometric ratios, and microbial resource limitation-related indicators between different fertilization treatments at the same sampling time 13 . The relationship between microbial resource limitation (vector angles in this study)and soil physical properties, microbial biomass C, N, P, and their stoichiometric ratios was analyzed by linear regression fitting using the "ggpmisc" package 49 . A heatmap of correlation coefficients in the "corrplot" package assesses the correlation between soil, microbial biomass, and enzymatic C:N:P. What's more, Principal component analysis (PCA) was used to determine the effects of sampling time and fertilization treatments on soil, microbial biomass, and enzymatic C:N:P by the "prcomp" function in R 13 . The above statistical analysis and graphing were completed using Rstudio software package v.4.2.1. Results Effects of different sampling time and fertilization on soil, soil microbial biomass, enzymes, and their C:N:P stoichiometric ratios. SOC, TN, and TP were not affected by the interaction of sampling periods and fertilization treatments, nor were they affected by them alone (Table 1 ). The microbial fertilizer combined with compound fertilizer increased these contents in M and H periods. The SWC and soil pH were significantly affected by sampling times and were the lowest in the H period. While the soil pH was also affected by fertilization treatments and was the lowest in the T3 (Table 2 ). The C-acquire enzyme activities and MBN were affected by the interaction of sampling time and fertilization treatment. Except for N-acquire enzyme activities, all other microbial traits were affected by sampling times (Table 1 ). Microbial biomass carbon and nitrogen showed a trend of increasing, then decreasing, then increasing, while the MBP increased gradually with the extension of the growth period of flue-cured tobacco (Table 2 ). Only eC/N and eC/P among C, N, and P stoichiometry were significantly affected by the interactive effect of fertilization treatments at different sampling times (p < 0.05), but mN/P, mC/P, eC/N, eC/P, and eN/P were all strongly affected by sampling time (p < 0.05) (Table 1 ). The values of sC/N, sC/P, and sN/P were lower in CK and T1 treatment but higher in T2 and T3 treatment in the M period (Figs. 1 A- 1 C). The sC/P and sN/P also showed a higher content in T2 and T3 treatment than that in CK and T1 treatment in the H period (Figs. 1 B and 1 C). The mC/N was significantly higher in the T1 fertilization treatment than that in the CK and T2 in the F period and was the highest in CK treatment in the H period (p < 0.05) (Fig. 1 D). The mC/P in T3 treatment was higher than other treatments in R and F periods, but the difference between the 4 treatments in the M and H periods was not significant (Fig. 1 E). The mN/P in T3 treatment was the highest in H period (p < 0.05) (Fig. 1 F).The eC/N and eC/P in T3 treatment were higher than in other treatments in M period, but the content were higher in T1 than that in T3 treatment in the H period (p 0.05) (Fig. 1 I). Table 1 Permutational multivariate analysis of variance (PERMANOVA) to assess the effects of fertilization treatment, sampling periods and their interactions on soil resources and C, N, and P stoichiometry; and enzymatic angle vectors. Treatment Sampling periods Treatment*Sampling periods F p F p F p SWC (%) 1.734 0.171 61.432 0.001*** 0.801 0.629 pH 4.904 0.008** 16.043 0.001*** 2.106 0.060 SOC (g/kg) 1.201 0.316 1.745 0.196 0.830 0.608 TN (g/kg) 1.611 0.221 1.532 0.237 1.161 0.345 TP (g/kg) 1.446 0.265 1.558 0.229 0.535 0.883 C-acq (umol/d/g) 0.718 0.570 17.760 0.001*** 5.883 0.001*** N-acq (umol/d/g) 0.511 0.665 2.586 0.070 1.226 0.301 P-acq (umol/d/g) 0.591 0.616 7.244 0.003** 0.317 0.956 MBC (mg/kg) 0.740 0.531 8.818 0.002** 2.007 0.064 MBN (mg/kg) 0.644 0.624 3.178 0.036* 2.691 0.023* MBP (mg/kg) 0.404 0.760 4.424 0.009** 0.567 0.829 C-acq/MBC 0.471 0.695 8.158 0.001*** 2.888 0.009** N-acq/MBN 1.456 0.268 11.798 0.001*** 2.901 0.014* P-acq/MBP 0.392 0.765 4.560 0.012* 0.972 0.476 sC/N 0.426 0.758 1.316 0.281 0.375 0.944 sC/P 0.194 0.906 2.556 0.072 0.345 0.952 sN/P 0.068 0.965 0.702 0.549 0.338 0.959 mC/N 1.400 0.253 1.388 0.247 0.836 0.591 mC/P 1.374 0.289 7.301 0.001 *** 0.561 0.865 mN/P 0.956 0.441 4.104 0.027 * 0.934 0.508 eC/N 0.363 0.765 7.488 0.001*** 3.535 0.012 * eN/P 0.325 0.815 6.869 0.001 *** 0.540 0.842 eC/P 0.497 0.690 11.930 0.001 *** 5.074 0.001 *** Vector angle 0.403 0.750 6.477 0.001*** 0.570 0.817 Notes: SWC, soil water content; pH, soil pH; SOC, soil organic carbon; TN, soil total nitrogen; TP, soil total phosphorus; C-acq, BG; N-acq, NAG + LAP; P-acq, ACP; MBC, microbial biomass C; MBN, microbial biomass N; NBP, microbial biomass P; C-acq/MBC, C related enzyme activity to microbial biomass C; N-acq/MBN, N related enzyme activity to microbial biomass N; P-acq/MBP, P related enzyme activity to microbial biomass P; sC/N, SOC/TN; sC/P, SOC/TP; sN/P, TN/TP; mC/N, MBC/MBN; mC/P, MBC/MBP;mN/P, MBN/MBP. eC/N, BG/(NAG + LAP); eC/P, BG/ACP; eN/P, (NAG + LAP)/ACP. The vector angle represents soil N and P limits for microorganisms. Table 2 Soil physicochemical properties and biological indicators across different treatments during the flue-cured tobacco growing period. Treatment SWC (%) pH SOC(g/kg) TN (g/kg) TP (g/kg) C-acq (umol/d/g) N-acq (umol/d/g) P-acq (umol/d/g) MBC (mg/kg) MBN (mg/kg) MBP (mg/kg) R-CK 0.25 ± 0.02a 6.77 ± 0.07ab 15.30 ± 0.76a 1.27 ± 0.01a 1.08 ± 0.03a 7.72 ± 0.71a 15.64 ± 1.94a 18.88 ± 1.26a 49.97 ± 1.70a 3.11 ± 0.04a 1.40 ± 0.29a R-T1 0.23 ± 0.01a 6.90 ± 0.06a 17.83 ± 1.47a 1.47 ± 0.07a 1.21 ± 0.12a 6.09 ± 0.86a 17.95 ± 1.12a 18.00 ± 1.65a 72.68 ± 5.64a 5.48 ± 1.89a 2.90 ± 1.08a R-T2 0.27 ± 0.02a 6.40 ± 0.15b 15.83 ± 1.03a 1.33 ± 0.12a 1.10 ± 0.03a 5.75 ± 0.68a 14.86 ± 1.82a 18.15 ± 1.68a 59.07 ± 5.43a 4.40 ± 1.26a 1.15 ± 0.30a R-T3 0.26 ± 0.02a 7.00 ± 0.00a 15.20 ± 0.46a 1.32 ± 0.05a 1.05 ± 0.06a 5.58 ± 0.08a 17.13 ± 0.92a 18.11 ± 1.85a 53.35 ± 9.69a 2.53 ± 0.08a 0.96 ± 0.31a F-CK 0.22 ± 0.02a 6.67 ± 0.03a 16.90 ± 1.21a 1.48 ± 0.10a 1.09 ± 0.01a 7.08 ± 1.39a 15.23 ± 1.72a 21.89 ± 1.62a 68.20 ± 10.57a 7.02 ± 1.65a 1.60 ± 0.39a F-T1 0.22 ± 0.02a 6.83 ± 0.27a 16.43 ± 0.98a 1.33 ± 0.04a 1.09 ± 0.04a 5.13 ± 0.22a 14.73 ± 1.84a 21.60 ± 1.88a 53.92 ± 1.50a 1.53 ± 0.49a 3.52 ± 0.70a F-T2 0.25 ± 0.01a 6.73 ± 0.20a 15.87 ± 0.66a 1.37 ± 0.04a 1.14 ± 0.02a 5.81 ± 0.26a 17.45 ± 0.29a 21.62 ± 1.00a 59.99 ± 6.71a 3.84 ± 1.77a 2.20 ± 0.98a F-T3 0.20 ± 0.02a 6.63 ± 0.12a 15.73 ± 0.92a 1.26 ± 0.08a 1.07 ± 0.05a 6.20 ± 1.30a 13.93 ± 1.43a 22.37 ± 0.07a 54.13 ± 6.34a 4.38 ± 1.90a 1.94 ± 1.00a M-CK 0.15 ± 0.01a 6.73 ± 0.15a 15.33 ± 0.81a 1.26 ± 0.02a 1.08 ± 0.04a 3.83 ± 0.40b 12.94 ± 1.07a 21.80 ± 1.21a 32.01 ± 8.22a 2.04 ± 0.13b 2.25 ± 0.95a M-T1 0.13 ± 0.01a 6.90 ± 0.06a 14.87 ± 0.20a 1.26 ± 0.05a 1.09 ± 0.04a 3.67 ± 0.33b 13.75 ± 0.47a 21.12 ± 1.24a 38.69 ± 2.96a 2.19 ± 0.60ab 3.62 ± 1.82a M-T2 0.14 ± 0.02a 6.47 ± 0.03a 15.27 ± 0.87a 1.33 ± 0.00a 1.09 ± 0.03a 3.66 ± 0.17b 14.63 ± 0.88a 21.80 ± 1.72a 35.16 ± 3.62a 2.42 ± 0.88ab 2.58 ± 0.81a M-T3 0.13 ± 0.01a 6.93 ± 0.15a 14.40 ± 0.81a 1.25 ± 0.06a 1.08 ± 0.06a 8.42 ± 1.40a 13.65 ± 0.63a 20.48 ± 1.79a 40.69 ± 10.83a 5.26 ± 0.89a 3.44 ± 1.27a H-CK 0.14 ± 0.00a 6.40 ± 0.00a 14.83 ± 0.47a 1.27 ± 0.03a 1.09 ± 0.04a 7.81 ± 0.14b 14.50 ± 0.23a 23.20 ± 1.36a 44.12 ± 9.17a 3.26 ± 0.91b 5.28 ± 0.59a H-T1 0.13 ± 0.01a 6.03 ± 0.07b 15.50 ± 1.05a 1.36 ± 0.05a 1.21 ± 0.10a 9.60 ± 0.42a 12.27 ± 0.54a 20.26 ± 0.55a 45.91 ± 11.55a 6.00 ± 0.78ab 3.47 ± 0.06a H-T2 0.13 ± 0.01a 6.17 ± 0.03ab 16.70 ± 0.65a 1.46 ± 0.09a 1.22 ± 0.02a 9.65 ± 0.21a 15.45 ± 2.58a 23.57 ± 1.15a 68.47 ± 5.45a 6.57 ± 0.66ab 5.41 ± 2.20a H-T3 0.11 ± 0.01a 6.47 ± 0.13a 14.97 ± 0.57a 1.33 ± 0.03a 1.14 ± 0.07a 6.77 ± 0.14b 16.57 ± 1.892a 22.86 ± 0.37a 70.95 ± 7.21a 9.01 ± 1.44a 3.62 ± 0.33a Notes: SWC, soil water content; pH, soil pH; SOC, soil organic carbon; TN, soil total nitrogen; TP, soil total phosphorus; C-acq, BG; N-acq, NAG + LAP; P-acq, ACP; MBC, microbial biomass C; MBN, microbial biomass N; NBP, microbial biomass P. The R, F, M, and H mean the root extending, flourishing, mature and harvest sampling period. CK, conventional fertilization; T1, conventional fertilization + microbial fertilizer; T2, 75% conventional fertilization + microbial fertilizer; T3, microbial fertilizer. Values are means ± standard error (n = 3). Lowercase letters indicate significant differences among different fertilizer treatments for each growing period, respectively (TukeyHSD test, p 0.05), which indicates that soil homeostasis was always strictly homeostatic among different fertilization treatments in the same period (Table 3 ). The above results showed that the soil microbial stoichiometric ratios are not affected by soil resources. Table 3 Homeostasis coefficients of soil microbial biomass and their stoichiometry. Sampling Time Variable(x) Variable(y) 1/H R 2 P Grade R SOC MBC 0.408 0.079 0.375 strictly homeostatic TN MBN 0.926 0.020 0.660 strictly homeostatic TP MBP -20.000 0.240 0.106 strictly homeostatic sC/N mC/N 0.078 0.268 0.268 strictly homeostatic sC/P mC/P 0.091 0.228 0.228 strictly homeostatic sN/P mN/P 0.671 0.238 0.238 strictly homeostatic F SOC MBC 0.341 0.036 0.553 strictly homeostatic TN MBN 2.757 0.037 0.548 strictly homeostatic TP MBP 2.328 0.030 0.593 strictly homeostatic sC/N mC/N -0.175 0.142 0.227 strictly homeostatic sC/P mC/P 0.092 0.105 0.303 strictly homeostatic sN/P mN/P 2.545 0.000 0.955 strictly homeostatic M SOC MBC 0.599 0.032 0.577 strictly homeostatic TN MBN 1.210 0.002 0.903 strictly homeostatic TP MBP 2.545 0.312 0.059 strictly homeostatic sC/N mC/N -0.397 0.049 0.489 strictly homeostatic sC/P mC/P 5.977 0.017 0.687 strictly homeostatic sN/P mN/P -1.530 0.064 0.428 strictly homeostatic H SOC MBC 0.215 0.003 0.871 strictly homeostatic TN MBN 0.613 0.003 0.877 strictly homeostatic TP MBP 0.704 0.000 0.999 strictly homeostatic sC/N mC/N 0.180 0.006 0.814 strictly homeostatic sC/P mC/P 0.169 0.052 0.477 strictly homeostatic sN/P mN/P 1.565 0.145 0.223 strictly homeostatic Notes: 1/H is the slope of the regression line between ln (y) and ln (x), where x is the soil resource stoichiometric ratio (e.g.sC/N), y is the microbial biomass carbon, nitrogen, and phosphorus stoichiometric ratio (e.g. mC/N). The regression relationship was not significant ( p > 0.05) in this study, so the microbial stoichiometry was considered to be "strictlyhomeostatic". The R, F, M, and H mean the root extending, flourishing, mature, and harvest sampling period. SOC, soil organic carbon; TN, soil total nitrogen; TP, soil total phosphorus; MBC, microbial biomass C; MBN, microbial biomass N; MBP, microbial biomass P; sC/N, SOC/TN; sC/P, SOC/TP; sN/P, TN/TP; mC/N, MBC/MBN; mC/P, MBC/MBP;mN/P, MBN/MBP. Soil C, N, and P cycle-related enzyme activities and microbial resource limitations. The C-acq/MBC, N-acq/MBN, and P-acq/MBP were all significantly affected by sampling time, at the same time, the C-acq/MBC and N-acq/MBN were also affected by the interaction of sampling times and fertilization treatments (p < 0.05) (Table 1 ). The C-acq/MBC was significantly higher in T3 treatment at the M period of flue-cured tobacco (p < 0.05) (Fig. 2 A). N-acq/MBN was significantly higher in the T1 treatment than in the other treatments at F period (p < 0.05) (Fig. 2 B). The ratios of N-acq/MBN and P-acq/MBP decreased as the flue-cured tobacco entered the H period (Figs. 2 B and 2 C). The vector angle of the four treatments at different sampling times (p T2 > CK > T3 in the M and H periods (Fig. 3 A). On the other hand, almost all the soil enzyme stoichiometry points, except for the samples from the R period, at the whole growth period, were above the 1:1 line (Fig. 3 B), indicating that the sample is P limited except for the N limitation at the R period. All soils were not limited by C and N co-limitation or C and P co-limitation (Fig. 3 C). What's more, the linear regression analysis as shown in Table 4 resulted that the soil vector angle, which almost indicated the phosphorous limitation in this study, were decreased with increasing SWC, pH, MBC, and mC/P (p < 0.05). Table 4 Linear regression of soil physicochemical and microbial indicators with vector angles Variables(x) regression equation R square p SWC y = 59.2-39.8x 0.23 0.001 pH y = 91.4-5.97x 0.14 0.005 SOC y = 56.2-0.28x 0.01 0.556 TN y = 54.7-2.14x 0.01 0.741 TP y = 56.5-4.19x 0.01 0.585 MBC y = 57.9-0.114x 0.13 0.006 MBN y = 51.6 + 0.0553x 0.01 0.839 MBP y = 50.5 + 0.459x 0.02 0.164 SCN y = 57.5-0.479x 0.01 0.590 SCP y = 52.1-0.0177x 0.01 0.974 SNP y = 49.5 + 1.96x 0.01 0.772 mC/N y = 53.4-0.1x 0.04 0.11 mC/P y = 54.2-0.0778x 0.18 0.001 mN/P y = 53.3-0.62x 0.05 0.064 Notes: SWC, soil water content; pH, soil pH; SOC, soil organic carbon; TN, soil total nitrogen; TP, soil total phosphorus; C-acq, BG; N-acq, NAG + LAP; P-acq, ACP; MBC, microbial biomass C; MBN, microbial biomass N; MBP, microbial biomass P. Correlation of soil, soil microbial biomass and enzyme-related C, N and P stoichiometric ratios. The principal component analysis results showed that axes 1 and 2 explained 25.8% and 24.0% of the variation in the soil resources, microbial biomass, and enzyme stoichiometry. The differences in soil and microbial C, N, and P indexes in different sampling times were greater than the differences between different fertilization treatments (Figs. 4 A and 4 B). The differences in the R and F periods were higher than that in M and H periods (Fig. 4 A). The correlation analysis results further showed that there was no significant relationship between mC/N and sC/N, mC/P and sC/P, and mN/P and sN/P. However, the soil eC/P and eC/N, mC/P and mN/P, sC/P, and sC/N were positively correlated. At the same time, significant negative correlations were found between mC/N and eC/N, mC/N and mN/P, and sN/P and sC/N. Soil organic carbon, total nitrogen, and total phosphorus were significantly positively correlated, as well as significant positive correlations between MBC and SOC, MBN and TN, and MBP and TP (Fig. 4 C). Discussion The stoichiometric balance of soil resources is very critical for maintaining microbial metabolism and elemental dynamic balance, which can reflect the ability of microorganisms to decompose soil organic matter and release phosphorus, indicate the supply of soil nutrients during plant growth 8 , 27 , 50 . Consistent with the results of previous studies, the soil SOC, TN, and TP content in this study were significantly positive correlated (Fig. 4 C, p < 0.05), and there was a good interaction between SOC, TN, and TP 27 , 51 . Meanwhile, Tian et al. 27 showed that the mean values of soil C/N, C/P, and N/P were 11.9, 61, and 5.2 in China, respectively. The average C/N value (11.45) in this study was similar to the above-average value, considering that carbon is a structural element, and its accumulation and consumption processes are relatively steady 52 . The variability of soil C/N in different fertilization treatments among different sampling times is not significant in this study. Meanwhile, the average values of C/P and N/P were 14.1 and 1.2 in this study and were lower than the average value of soil in China, which may be due to the low organic carbon content in red soil in this study 53 ; or the lower pH, the lower nitrogen availability 54 . However, the addition of microbial fertilizer improved the value of soil C/P and N/P in the H period (Figs. 1 B and 1 C), which may be because Bacillus subtilis contained in the microbial fertilizer can improve soil nitrogen fixation capacity and increase soil organic carbon content 55 ; or Bacillus mucilaginosus can decompose soil silicate minerals, and convert insoluble substances such as potassium, phosphorus, and silicon into soluble substances that can be used for plant growth 56 . Interestingly, the reduced usage of compound fertilizer combined with microbial fertilizer (T2) in this study was more obvious for increasing soil C/P and N/P (Fig. 1 B and 1 C). Microbial resource limitation specifies that microbial growth and activity are often limited by nutrient availability and energy 57 . Ecological stoichiometry theory suggests that the C:N:P ratio of soil microbial biomass is more stable relative to the soil C, N, and P stoichiometry ratio and reflects the state of microbial C, N, and P demand 58 . Our results indicated that there was no significant correlation between microbial biomass stoichiometric ratio and soil resources stoichiometric ratio (Fig. 4 C). The strict homeostasis of soil microbial biomass in different fertilizations among different sampling times also confirmed that the stability of microbial stoichiometry 7 (Table 3 ). Moreover, the global average value of C/N, C/P, and N/P of soil microbial biomass was 7.6, 42.4, and 5.6, respectively 51 . The MBC/MBP and MBN/MBP were 30.52 and 2.37 in this study, which was lower than the global level. This result indicated that soil microorganisms had a weak tendency to assimilate soil available P, and the ability to absorb phosphorus was a weak result of the competition with plants 59 . However, the MBC/MBN (19.14) was higher than the global level, which suggested the relative strong nitrogen fixation ability of soil microorganisms in this study 60 . Consistently with previous studies 1 , the MBC/MBN is relatively stable in this study, and MBC/MBP and MBN/MBP varied more among different sampling periods (Fig. 1 A), indicating greater stoichiometric plasticity of microbial phosphorus 1 . In contrast to the previous study, Qi et al. 7 showed that soil MBC/MBP and MBN/MBP reached the maximum in the middle and late stages of forest vegetation growth (August). Our results showed that MBC/MBP and MBN/MBP were highest in the R period, and lower in M and H periods, which may be related to different ecosystem types and soil types 7 . Previous studies have indicated that the ratio of global soil C, N, and P-related enzyme activities is 1:1:1 61 . When the ratio deviates from 1:1:1, it may indicate that soil microorganisms are affected by carbon, nitrogen, or phosphorus limitation 61 . The C:N:P of enzyme activities was 1:1.45:1.64 in this study, which showed that soil microorganisms are more restricted by nitrogen and phosphorus than soil carbon. In addition, enzyme stoichiometry points were almost above the 1:1 line, and the vector angles in almost all treatments were greater than 45°, which both showed the P-limited, except for a few points of N-limited at the R period. Moreover, the soil microorganisms changed from N-limited to P-limited with the extension of the growth period 45 (Fig. 3 A). It should be noted that enzymatic stoichiometry is controversial in determining carbon resource constraints 24 , 30 . However, this study combined the C, N, and P enzyme stoichiometric characteristics and vector angle to determine the microbial resource limitation, and the tobacco planting soil in this study was limited by N and P, which could well avoid this bias, and the study results were very convincing. The limitation of soil N and P may be due to the acidic soil in this study. Previous research has suggested that the limitation of P is mainly due to the strong binding of Fe 3+ and Al 3+ or the water-soluble P is slowly converted into occluded phosphorus in the acid soil, resulting in the reduction of P utilization 62 , 63 . Secondly, with the extension of the growth period of flue-cured tobacco, the phosphorus limitation increased first and then decreased. The T3 treatment has an earlier weakening trend, and showed a weakening phenomenon from the F period to the M period, while the remaining treatments showed a weakening trend from M to H period. The changes in phosphorus limitation may be due to that a large amount of phosphorus is needed to supply the primary productivity of flue-cured tobacco in the vigorous growth period, thereby increasing the limitation of soil microorganisms on phosphorus 13 , and the phosphorus limitation was alleviated by increasing the soil total phosphorus in H period 64 (Table 2 ). The result also showed that the full application of microbial fertilizer (T3) had a more obvious effect on alleviating phosphorus limitation, which is conducive to microbial nutrient balance by alleviating nutrient competition between soil microbial and soils. Moreover, Yang et al. 12 showed that microbial nitrogen and phosphorus limitation was affected by soil nutrient stoichiometric ratio, soil water content, soil pH, soil bulk density, and soil organic C the key factor in microbial nitrogen and phosphorus limitation. At the same time, other studies have shown that temperature, soil moisture, soil pH, and SOC can affect microbial P limitation 12 , 65 . In this study, soil water content, soil pH, MBC, and mC/P had negative significant effects on microbial N and P limitation (Table 4 ). Consistent with previous results, the higher soil water content will accelerate the decomposition of soil organic carbon 12 , and result in enhancing microbial activity and microbial biomass carbon content, the soil nutrient limitation converts from nitrogen limitation to phosphorus limitation 66 . On the other hand, low soil pH, and mC/P can lead to reduced availability of P in soil, microorganisms also compete with plants for P, and biological fixation of P occurs, thereby aggravating P limitation 62 , 65 . In this study, soil water content, soil pH, and soil m C/P were decreased with the extension of the growth period, which may result in the weakening of phosphorus limitation in the H period (Table 2 ). Conclusions Soil resources, microbial biomass, enzyme activities, and stoichiometric ratios were generally more affected by sampling times than by fertilization treatments. The stoichiometric ratio of microbial C, N, and P was strict homeostasis and is not affected by the changes in soil C, N, and P stoichiometric ratio. While the soil microbial metabolism in tobacco-growing soils among different growth periods is more susceptible to phosphorus restriction, soil water content, soil pH, MBC and mC/P are the key factors to influence phosphorus limitation. We also found that the addition of microbial fertilizers can change the biophysical and chemical properties of the soil, and then affect the stoichiometric balance and microbial nutrients, effectively reducing the phosphorus limitation in this study, and the reduction effect is more obvious in the mature and harvest periods. This study links soil physicochemical properties with soil microbial metabolic limitations, which is beneficial to deepen our understanding of soil nutrient cycling mechanisms. Declarations Data availability All data generated and analyzed during this study are included in this published article. Acknowledgements This study was financially supported by the Scientific Research Foundation Project of the Yunnan Education Department (2022Y695), the Basic Research Joint Special Youth Project of Local Undergraduate Universities in Yunnan Province (2019FH001-098, 202101BA070001-057), and the College Students' innovation and entrepreneurship training program (S202211393048). Author contributions statement Conceptualization, Z, T. Data curation, J.F., T.X., Y.R., X.S. and L.C. Formal analysis, J.F. L.C. and Z, T. Funding acquisition, J.F., Y.Z. and Z,T. Investigation, T.X., Y.R., X.S. and Y.Z. Resources, X.S., T.W. and X.S. Writing-original draft, J.F. 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Also discoverable on Platform About In Review Editorial Policies Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-2145253","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":155010584,"identity":"8f6250df-320e-4268-bcd1-65650dff6136","order_by":0,"name":"Junna Feng","email":"","orcid":"","institution":"Kunming University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Junna","middleName":"","lastName":"Feng","suffix":""},{"id":155010585,"identity":"37a9c006-d549-41ef-8689-4b9014f4c869","order_by":1,"name":"Lulu Chen","email":"","orcid":"","institution":"Chinese Academy of Sciences","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Lulu","middleName":"","lastName":"Chen","suffix":""},{"id":155010586,"identity":"06d8a903-627a-423b-829b-b3a218d4c080","order_by":2,"name":"Tiyuan Xia","email":"","orcid":"","institution":"Kunming University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Tiyuan","middleName":"","lastName":"Xia","suffix":""},{"id":155010587,"identity":"85595858-577e-4a3e-8518-ebe4336babb3","order_by":3,"name":"Yanan Ruan","email":"","orcid":"","institution":"Yunnan Agricultural University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yanan","middleName":"","lastName":"Ruan","suffix":""},{"id":155010588,"identity":"296e3108-1074-4729-ad1a-d0076db6ed42","order_by":4,"name":"Xiaolu Sun","email":"","orcid":"","institution":"Qingdao Agricultural University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Xiaolu","middleName":"","lastName":"Sun","suffix":""},{"id":155010589,"identity":"80d847f1-37e6-4289-aa87-63fe2dbcd57c","order_by":5,"name":"Tian Wu","email":"","orcid":"","institution":"Kunming University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Tian","middleName":"","lastName":"Wu","suffix":""},{"id":155010590,"identity":"1d9fdb81-b89c-45e2-8eb5-536819f0f5f0","order_by":6,"name":"Yu Zhong","email":"","orcid":"","institution":"Kunming University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yu","middleName":"","lastName":"Zhong","suffix":""},{"id":155010591,"identity":"903bfb0e-1611-4b3e-a233-88b24d950280","order_by":7,"name":"Xiaodong Shao","email":"","orcid":"","institution":"Honghe Branch of Yunnan Tobacco Company","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Xiaodong","middleName":"","lastName":"Shao","suffix":""},{"id":155010592,"identity":"f20e75ef-8ef8-4f64-8247-355b557754a2","order_by":8,"name":"Zuoxin Tang","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3klEQVRIiWNgGAWjYBADHjb25oMPEipsiFAKpWX4eY4lGzw4k0a8FhvJGTlmkg/bDhHWYs9+9vDLn202PAYHcswqEtgOMPC3dyfgt4UnL81Csi0NqOVY2Y0EnjsMEmfObiDgsBwzA8O2wzwGB5u33UiQeMZgIJFLQAv/GzODRJCWwwxmBQlAkrAWiRzjBweBWiTbWMwYEhKI0XLjjRljw7k0Hn4etmSJhANpPAT9wt6fY/zxR5mNPZv844Mff/6zkeNv78WvBQjYJFCsJaQcBJg/EKNqFIyCUTAKRjAAAKQySG1pWNbEAAAAAElFTkSuQmCC","orcid":"","institution":"Kunming University","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Zuoxin","middleName":"","lastName":"Tang","suffix":""}],"badges":[],"createdAt":"2022-10-08 12:59:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-2145253/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-2145253/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41598-023-37438-w","type":"published","date":"2023-06-24T21:17:06+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":29680164,"identity":"2711ae42-93b6-48ff-a9ad-122cdade859f","added_by":"auto","created_at":"2022-11-29 18:59:07","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":206137,"visible":true,"origin":"","legend":"\u003cp\u003eC:N:P stoichiometry of soil, microbial biomass and CNP related enzyme activity with different sampling periods under different fertilization treatments. sC/N, SOC/TN; sC/P, SOC/TP; sN/P, TN/TP; mC/N, MBC/MBN; mC/P, MBC/MBP; mN/P, MBN/MBP. eC/N, BG/(NAG+LAP); eC/P, BG/ACP; eN/P, (NAG+LAP)/ACP. The R, F, M and H mean the root extending, flourishing, mature and harvest sampling period. CK, conventional fertilization; T1, conventional fertilization + microbial fertilizer; T2, 75% conventional fertilization + microbial fertilizer; T3, microbial fertilizer. Values are the means ± standard error (n = 3). Lowercase letters are used to show significant differences with fertilization (p\u0026lt; 0.05) based on one-way ANOVA followed by TukeyHSD test.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-2145253/v1/6fbea52546baf5dcc4fdac8e.png"},{"id":29680885,"identity":"0cd525da-68aa-4d8b-9035-b6f355b36956","added_by":"auto","created_at":"2022-11-29 19:07:07","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":167677,"visible":true,"origin":"","legend":"\u003cp\u003eThe ratio of soil CNP related enzyme activity to microbial biomass CNP (specific enzyme activity per microbial biomass unit: microbial enzyme activity coefficient) with different sampling periods under different fertilization treatments. The R, F, M and H mean the root extending, flourishing, mature and harvest sampling period. CK, conventional fertilization; T1, conventional fertilization + microbial fertilizer; T2,75% conventional fertilization + microbial fertilizer; T3, microbial fertilizer. Values are the means ± standard error (n = 3). Lowercase letters are used to show significant differences with fertilization (p\u0026lt; 0.05) based on one-way ANOVA followed by TukeyHSD test.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-2145253/v1/02c61ab710bea19884530be1.png"},{"id":29680161,"identity":"5e60a779-75a9-4264-ac35-c3a1b7017031","added_by":"auto","created_at":"2022-11-29 18:59:07","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":79983,"visible":true,"origin":"","legend":"\u003cp\u003eChanges of vector angle with different sampling periods under different fertilization treatments (B) and the relationship between soil carbon, nitrogen and phosphorus cycle related enzymes (A, C). The vector angles represent soil N and P limits for microorganisms. while vector angles below 45° indicate N-limitation; above 45° indicate P-limitation. The R, F, M and H mean the root extending, flourishing, mature and harvest sampling period. CK, conventional fertilization; T1, conventional fertilization + microbial fertilizer; T2, 75% conventional fertilization + microbial fertilizer; T3, microbial fertilizer.\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-2145253/v1/967142303a8f0b7f72569b44.png"},{"id":29680163,"identity":"16fd270b-0176-4090-99b9-5e75c68b8968","added_by":"auto","created_at":"2022-11-29 18:59:07","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":330984,"visible":true,"origin":"","legend":"\u003cp\u003ePrincipal component analysis (PCA) of soil resources, soil microbial biomass and enzyme-related stoichiometric ratios of C, N and P (A -B) and the correlation of soil physicochemical and microbial indicators (C). The R, F, M and H mean the root extending, flourishing, mature and harvest sampling period. CK, conventional fertilization; T1, conventional fertilization + microbial fertilizer; T2, 75% conventional fertilization + microbial fertilizer; T3, microbial fertilizer. Red and blue represent positive and negative correlations, respectively. The darker the color, the stronger the relationship. *: The correlation is significant at the p\u0026lt; 0.05 level; **: The correlation is significant at the p\u0026lt; 0.01 level; ***: The correlation is significant at the p\u0026lt; 0.001 level.\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-2145253/v1/ec8fddf252f262ae55324923.png"},{"id":44731428,"identity":"5b8ce34d-0763-4e99-8d62-791f9e9c21f8","added_by":"auto","created_at":"2023-10-16 21:43:46","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1283331,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-2145253/v1/956471bc-721b-4349-b086-89e0192e941b.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Microbial fertilizer regulates C:N:P stoichiometry and alleviates phosphorus limitation in flue-cured tobacco planting soil","fulltext":[{"header":"Introduction","content":"\u003cp\u003eIn the global biogeochemical cycle, carbon (C), nitrogen (N) and phosphorus (P) play pivotal roles in plant growth and soil fertility, and their interactions are closely intertwined through a series of physical, chemical, and biological processes\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e,\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e. Ecological stoichiometry provides an extremely effective and integrated approach to studying this coupling and knowing the changes in element ratios\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e. The ecological stoichiometric ratio of C, N, and P can reflect the relationship between soil, microorganisms, and enzymes, and have been widely used in the study of nutrient supply and demand balance in different ecosystems\u003csup\u003e\u003cspan additionalcitationids=\"CR5 CR6\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eSoil C:N:P stoichiometry is a functional trait that reflects nutrient use efficiency and nutrient limitation\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e, and can maintain ecosystem functions against global change\u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e. In plant-soil systems, the C:N:P ratio regulates microbial community composition and maintains a balance between element uptake and release. The decomposition of soil organic matter is controlled by soil microbes, which affects the balance of carbon, nitrogen, and phosphorus in the ecosystem\u003csup\u003e\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e. The microbial C:N:P ratio determines the direction of microbial activity and the release of organic nutrients\u003csup\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e. Soil C, N, and P availability generally limit the metabolism of microorganisms\u003csup\u003e\u003cspan additionalcitationids=\"CR13\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e. When soil microbial resources are limited, plant-microbe competition for nutrients increases, posing a threat to plant colonization and growth\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e,\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e. Therefore, It is important to know the relationship between soil C:N:P ratio and soil microbial C:N:P ratio to understand soil microbial nutrient limitations\u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eAdditionally, the enzyme stoichiometric ratio can reflect the metabolic function of the microbial community and the biological cycle of nutrients in the environment\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e,\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e. As an indicator of the carbon, nitrogen, and phosphorus requirements of soil microorganisms, the enzyme stoichiometric ratio can also be calculated\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e,\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e. We believe that it is the result of the interaction of various microorganisms with other factors (including temperature, moisture, nitrogen, phosphorus, and crop roots), which indirectly reflects the availability of soil resources\u003csup\u003e\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e,\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u003c/sup\u003e. It is an effective indicator for evaluating the limit of soil microbial resources\u003csup\u003e\u003cspan additionalcitationids=\"CR13\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e. Currently, the most commonly used method to characterize soil microbial resource limitations is the ratio of carbon, nitrogen, and phosphorus-related enzyme activities, enzyme stoichiometric vector analysis (vector length and vector angle), and threshold elements ratios (TERC:N and TERC:P)\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e,\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e,\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e. Patterns of soil resource limitation in cultivated land based on enzyme stoichiometry have been reported in different regions. For instance, Cui et al.\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e reported that the C:N:P ratio of microbial enzyme activities, vector angle, threshold elements C:N, and C:P ratios for farmland in Jilin Province, China, arguing that microbial metabolism was mainly nitrogen-limited under organic fertilizer treatments. Wang et al.\u003csup\u003e24\u003c/sup\u003eobserved that the combined application of organic and chemical fertilizers could reduce soil carbon limitation in tobacco planting soils in Yunnan based on the study of vector length and angle. Furthermore, some evidence suggests that there may be a dynamic equilibrium relationship between the stoichiometric ratio of soil extracellular enzymes and the stoichiometric ratio of soil and microorganisms\u003csup\u003e\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u003c/sup\u003e. In areas with relatively restricted environments, the stoichiometric ratio of enzymes remains relatively stable, and microorganisms need to maintain the relative balance between acquisition and investment of various elements to better cope with nutrient deficiencies and maintain soil nutrient dynamic equilibrium\u003csup\u003e\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e. Yin et al.\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e studied the stoichiometric characteristics of C, N, and P in soil microbial extracellular enzymes in Northeast China, and found that extracellular enzyme N:P was significantly negatively correlated with soil N:P; a significant positive correlation between extracellular enzyme C:N and microbial C:N. Therefore, an integrated analysis of C, N, P stoichiometric characteristics of soil resources, and microbial and enzymatic activities is necessary for the study of ecological chemometrics.\u003c/p\u003e \u003cp\u003eFertilizer application is a key agricultural practice to maintain or improve the fertility of agricultural soils. The nutrient content of farmland soil changes with fertilization. These changes alter the soil C, N, and P stoichiometry, and greatly affect the C, N, and P of soil enzyme activities and microbial biomass\u003csup\u003e\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e,\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e,\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e. The imbalance between soil microbial demand and soil substrate supply can affect C, N, and P nutrient cycling\u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e. Typically, N is a key nutrient limiting the net primary productivity of agroecosystems\u003csup\u003e\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e\u003c/sup\u003e, and fertilizer application reduce N availability by increasing soil carbon fixation. For instance, Shen et al.\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e observed that replacing 20% or 50% of chemical fertilizers combined with organic fertilizers will aggravate soil microbial nitrogen limitation in greenhouse soils for vegetable cultivation\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e. In arid and semi-arid regions, organic fertilizers alone or in combination with nitrogen fertilizers can aggravate nitrogen limitation\u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e. Recent studies have shown that phosphorus limitation is common in agroecology\u003csup\u003e\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e,\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e\u003c/sup\u003e, and the application of organic nitrogen to replace chemical fertilizer nitrogen application is beneficial to relieve soil microbial carbon limitation and phosphorus limitation\u003csup\u003e\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e\u003c/sup\u003e. Tobacco is an important economic crop in Yunnan Province, and the yield and quality were affected by many factors including the climate, fertilization management, crop rotation pattern, soil properties, and soil microorganisms\u003csup\u003e\u003cspan additionalcitationids=\"CR34\" citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e\u003c/sup\u003e. Previous studies on the C, N, and P stoichiometry were used to reflect flue-cured tobacco soil fertility levels\u003csup\u003e\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e\u003c/sup\u003e. However, to our knowledge, only a few studies have elucidated the effects of different fertilization treatments on the limitation of microbial resources in tobacco-growing soils in recent years\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e,\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e. On the other hand, many studies have confirmed that microbial fertilizers instead of chemical fertilizers can promote the absorption and transformation of soil available nutrients while reducing environmental pollution, and improving soil fertility\u003csup\u003e\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e\u003c/sup\u003e. However, there are few studies on the effect of microbial fertilizer application on microbial resource limitation. Therefore, from the perspective of rational fertilization and improvement of soil fertility, it is very important to study the changes in soil microbial resource limitation under different fertilization strategies.\u003c/p\u003e \u003cp\u003eFinally, the ecological stoichiometric properties of soil C, N, and P in different ecosystems were significantly affected by the sampling period. Qi et al.\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e indicated that soil and microbial-related properties and their C:N:P ratios were more influenced by the sampling stage than by the forest type. Jin et al.\u003csup\u003e\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e\u003c/sup\u003e showed that the C, N, and P ratio of paddy soil was significantly higher in the jointing period than that in the mature period. These studies demonstrated that it is beneficial to determine the stoichiometric characteristics of C, N, and P in different sampling periods to reflect the soil nutrient requirements more accurately and to know the changes of plant elements in different growth periods. In this study, we investigated the relationship between soil, microbial, and enzyme activity C, N, and P stoichiometry during the tobacco growing season and the response of microbial resource limitation to microbial fertilizer application, we intend to address the following two questions: 1) Does microbial fertilizer application lead to changes in a stoichiometric ratio of soil and microbial biomass C, N, P, compared to conventional fertilizer application? 2) What factors influence the limitation of microbial resources in tobacco-planted soils?\u003c/p\u003e"},{"header":"Materials And Methods","content":"\u003cp\u003e \u003cb\u003eEthics statement.\u003c/b\u003e The authors promise that all the methods were performed in accordance with relevant guidelines and regulations.\u003c/p\u003e \u003cp\u003e \u003cb\u003eStudy area, experiment design, and soil sampling.\u003c/b\u003e The experiment site is located at the new flue-cured tobacco technology test base of Ganlanpo, in Mile, Hani-Yi Autonomous Prefecture of Honghe, Yunnan, China (103\u0026deg;27\u0026prime;E; 24\u0026deg;23\u0026prime;N, elevation 1451 m). The average annual rainfall, temperature and sunshine hours were 990.4 mm, 18.8\u0026deg;C, and 2131.4 h, respectively. The soil type is red soil and the previous crop is wheat. The major soil properties of the field before transplanting were as follows: pH of 6.09, the contents of soil organic carbon (SOC), soil total nitrogen (TN), soil total phosphorus (TP) and total potassium were 15.20, 1.34, 1.03, and 5.37 g/kg, and the contents of soil alkali-hydrolyzed nitrogen, available potassium and available phosphorus were 121.87, 14.76 and 193.41 mg/kg. This experiment was randomly distributed, with four treatments and three replicates: conventional fertilization (CK); conventional fertilization\u0026thinsp;+\u0026thinsp;microbial fertilizer (T1); 75% conventional fertilization\u0026thinsp;+\u0026thinsp;microbial fertilizer (T2), and microbial fertilizer alone (T3). Among them, the conventional fertilization is humic acid organic-inorganic compound fertilizer 50g/plant (N\u0026thinsp;+\u0026thinsp;P\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e\u0026thinsp;+\u0026thinsp;K\u003csub\u003e2\u003c/sub\u003eO \u0026ge;\u0026thinsp;33%, 8-5-20) and the microbial fertilizer 80 g/plant (CociCoLi, which was produced by Wuhan Kenuo Biotechnology Co., Ltd., the number of effective viable bacteria is more than 200\u0026nbsp;million/g, organic matter\u0026thinsp;\u0026ge;\u0026thinsp;60%, humic acid\u0026thinsp;\u0026ge;\u0026thinsp;10%). The microbial fertilizer was used as base dressing before transplanting and the compound fertilizer was fertilized by annularity fertilizing when transplanting. The test variety was the local main variety, K326, the use of base and top-dressing fertilizer, picking, and backing were set up in line with local management methods\u003csup\u003e\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e\u003c/sup\u003e. The row spacing of tobacco plants is 1.2m\u0026times;0.55m, 1000 plants/acre, and each treatment plot has 60 tobacco plants, about a total of 40 m\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e (excluding the protected lines).\u003c/p\u003e \u003cp\u003eThe rhizosphere soil samples were collected according to the method of Wang et al.\u003csup\u003e34\u003c/sup\u003eduring the root extending period (6\u0026ndash;8 leaves), flourishing period (13\u0026ndash;14 leaves), mature period (3\u0026ndash;5 days before harvesting), and harvest period, and named in the order of R, F, M, H. The collected soil samples were mixed according to the same treatment, sieved after removing impurities, stored in a sealed bag, and transported back to the laboratory for preservation within 24 hours. Each sample was divided into two parts, one naturally dried for the determination of basic physicochemical properties of the soil and the other stored at -20\u0026deg;C for the determination of soil microbial properties.\u003c/p\u003e \u003cp\u003e \u003cb\u003eDetermination of soil physical, chemical, and microbial properties.\u003c/b\u003e The soil water content (SWC) was calculated by the amount of loss after dried 48 h by using the method of NY/T1121.3-2006. Soil pH was measured in water (1:2.5 w/v) according to NY/T1377-2007 by using a pH meter (PHS-3C). The SOC, TN, and TP contents were measured according to HJ 695\u0026ndash;2014, NY/T 53-1987, and NY/T 88-1988, respectively. The soil microbial biomass contents of carbon, nitrogen, and phosphorus (MBC, MBN, and MBP) were measured according to the chloroform-fumigation-extraction method\u003csup\u003e\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e\u003c/sup\u003e, and a conversion factor E of microbial biomass carbon, nitrogen, and phosphorus was 0.38, 0.57, 040, respectively\u003csup\u003e\u003cspan additionalcitationids=\"CR41 CR42\" citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e\u003c/sup\u003e. We also calculated a range of soil and microbial ratios, such as SOC/TN (sC/N), SOC/TP (sC/P), TN/TP (sN/P), MBC/MBN (mC/N), MBC/MBP (mC/P) and MBN/MBP (mN/P) in this study.\u003c/p\u003e \u003cp\u003eThe activities of four common C, N, and P-related hydrolytic enzymes includingβ-1,4-glucosidase (BG), β-1,4-N-acetyl-glucosaminidase (NAG), leucine aminopeptidase (LAP), and acid phosphatase (ACP) were measured in this study. The activities of BG and NAG were determined according to the previously described method\u003csup\u003e\u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e\u003c/sup\u003e. The LAP and ACP activities were measured using a physiological assay kit (Suzhou Keming Biological Technology Co., Ltd., Suzhou, China) according to the manual. Like many other studies, BG, (NAG\u0026thinsp;+\u0026thinsp;LAP) and ACP were used to be C-acquire enzyme activities(C-acq), N-acquire enzyme activities (N-acq), and P-acquire enzyme activities (P-acq)\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e. On the other hand, we calculated the stoichiometric ratios of C, N, P microbial enzyme activity, including BG to (NAG\u0026thinsp;+\u0026thinsp;LAP) (eC/N), BG to ACP (eC/P), and (NAG\u0026thinsp;+\u0026thinsp;LAP) to ACP (eN/P)\u003csup\u003e13\u003c/sup\u003e. We also calculated the specific enzyme activity per unit of microbial biomass, like BG/MBC (C-acq/MBC), (NAG\u0026thinsp;+\u0026thinsp;LAP)/MBN (N-acq/MBN), and ACP/MBP (P-acq/MBP) to represent microbial enzyme activity coefficient\u003csup\u003e\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e. Finally, we calculated the vector angle, and the ratio of C, N, and P enzyme activity to characterize the enzyme stoichiometry\u003csup\u003e\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e\u003c/sup\u003e, and we calculated the microbial stoichiometric homeostasis\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e,\u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e,\u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003e \u003cb\u003eStatistical Analysis.\u003c/b\u003e A permutation multivariate analysis of variance (PERMANOVA) was conducted to determine the effect and significance of sampling time and fertilization treatments and their interactions on soil indicators by using the \"vegan\" package of R\u003csup\u003e\u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e48\u003c/span\u003e\u003c/sup\u003e. In this study, the \"Shapiro.test\" and \"Levene-test\" were used to perform the normal distribution test and homogeneity of variance test. The logarithmic or reciprocal transformation was carried out for the indicators that did not conform to the normal distribution. For the indicators that failed converted, the significance of differences between groups was used in the nonparametric test (Kruskal-Wallis). one-way analysis of variance (ANOVA) and Tukey's \" honestly significant difference\" (HSD) test were used to determine whether differences in soil basic physical and chemical properties, soil, microbial, and related enzyme C, N, P stoichiometric ratios, and microbial resource limitation-related indicators between different fertilization treatments at the same sampling time\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e. The relationship between microbial resource limitation (vector angles in this study)and soil physical properties, microbial biomass C, N, P, and their stoichiometric ratios was analyzed by linear regression fitting using the \"ggpmisc\" package\u003csup\u003e\u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e49\u003c/span\u003e\u003c/sup\u003e. A heatmap of correlation coefficients in the \"corrplot\" package assesses the correlation between soil, microbial biomass, and enzymatic C:N:P. What's more, Principal component analysis (PCA) was used to determine the effects of sampling time and fertilization treatments on soil, microbial biomass, and enzymatic C:N:P by the \"prcomp\" function in R\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e. The above statistical analysis and graphing were completed using Rstudio software package v.4.2.1.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e \u003cb\u003eEffects of different sampling time and fertilization on soil, soil microbial biomass, enzymes, and their C:N:P stoichiometric ratios.\u003c/b\u003e SOC, TN, and TP were not affected by the interaction of sampling periods and fertilization treatments, nor were they affected by them alone (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The microbial fertilizer combined with compound fertilizer increased these contents in M and H periods. The SWC and soil pH were significantly affected by sampling times and were the lowest in the H period. While the soil pH was also affected by fertilization treatments and was the lowest in the T3 (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The C-acquire enzyme activities and MBN were affected by the interaction of sampling time and fertilization treatment. Except for N-acquire enzyme activities, all other microbial traits were affected by sampling times (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Microbial biomass carbon and nitrogen showed a trend of increasing, then decreasing, then increasing, while the MBP increased gradually with the extension of the growth period of flue-cured tobacco (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Only eC/N and eC/P among C, N, and P stoichiometry were significantly affected by the interactive effect of fertilization treatments at different sampling times (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05), but mN/P, mC/P, eC/N, eC/P, and eN/P were all strongly affected by sampling time (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The values of sC/N, sC/P, and sN/P were lower in CK and T1 treatment but higher in T2 and T3 treatment in the M period (Figs.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA-\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eC). The sC/P and sN/P also showed a higher content in T2 and T3 treatment than that in CK and T1 treatment in the H period (Figs.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eB and \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eC). The mC/N was significantly higher in the T1 fertilization treatment than that in the CK and T2 in the F period and was the highest in CK treatment in the H period (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eD). The mC/P in T3 treatment was higher than other treatments in R and F periods, but the difference between the 4 treatments in the M and H periods was not significant (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eE). The mN/P in T3 treatment was the highest in H period (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eF).The eC/N and eC/P in T3 treatment were higher than in other treatments in M period, but the content were higher in T1 than that in T3 treatment in the H period (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05)(Figs.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eG and \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eH). There were no significant differences in eN/P among the four treatments in all growth periods (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eI).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePermutational multivariate analysis of variance (PERMANOVA) to assess the effects of fertilization treatment, sampling periods and their interactions on soil resources and C, N, and P stoichiometry; and enzymatic angle vectors.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eTreatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eSampling periods\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eTreatment*Sampling periods\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSWC (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.734\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.171\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e61.432\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.001***\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.801\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.629\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003epH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4.904\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.008**\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e16.043\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.001***\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.106\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.060\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSOC (g/kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.201\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.316\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.745\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.196\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.830\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.608\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTN (g/kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.611\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.221\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.532\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.237\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.161\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.345\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTP (g/kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.446\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.265\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.558\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.229\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.535\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.883\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eC-acq (umol/d/g)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.718\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.570\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17.760\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.001***\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.883\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.001***\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN-acq (umol/d/g)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.511\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.665\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.586\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.070\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.226\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.301\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eP-acq (umol/d/g)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.591\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.616\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.244\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.003**\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.317\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.956\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMBC (mg/kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.740\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.531\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.818\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.002**\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.007\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.064\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMBN (mg/kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.644\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.624\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.178\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.036*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.691\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.023*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMBP (mg/kg)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.404\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.760\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.424\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.009**\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.567\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.829\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eC-acq/MBC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.471\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.695\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.158\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.001***\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.888\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.009**\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN-acq/MBN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.456\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.268\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e11.798\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.001***\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.901\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.014*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eP-acq/MBP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.392\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.765\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.560\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.012*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.972\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.476\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003esC/N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.426\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.758\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.316\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.281\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.375\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.944\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003esC/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.194\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.906\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.556\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.072\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.345\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.952\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003esN/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.068\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.965\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.702\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.549\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.338\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.959\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003emC/N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.400\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.253\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.388\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.247\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.836\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.591\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003emC/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.374\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.289\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.301\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.001 ***\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.561\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.865\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003emN/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.956\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.441\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.104\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.027 *\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.934\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.508\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eeC/N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.363\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.765\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.488\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.001***\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.535\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.012 *\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eeN/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.325\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.815\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.869\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.001 ***\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.540\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.842\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eeC/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.497\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.690\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e11.930\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.001 ***\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.074\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.001 ***\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVector angle\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.403\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.750\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.477\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.001***\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.570\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.817\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003eNotes: SWC, soil water content; pH, soil pH; SOC, soil organic carbon; TN, soil total nitrogen; TP, soil total phosphorus; C-acq, BG; N-acq, NAG\u0026thinsp;+\u0026thinsp;LAP; P-acq, ACP; MBC, microbial biomass C; MBN, microbial biomass N; NBP, microbial biomass P; C-acq/MBC, C related enzyme activity to microbial biomass C; N-acq/MBN, N related enzyme activity to microbial biomass N; P-acq/MBP, P related enzyme activity to microbial biomass P; sC/N, SOC/TN; sC/P, SOC/TP; sN/P, TN/TP; mC/N, MBC/MBN; mC/P, MBC/MBP;mN/P, MBN/MBP. eC/N, BG/(NAG\u0026thinsp;+\u0026thinsp;LAP); eC/P, BG/ACP; eN/P, (NAG\u0026thinsp;+\u0026thinsp;LAP)/ACP. The vector angle represents soil N and P limits for microorganisms.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSoil physicochemical properties and biological indicators across different treatments during the flue-cured tobacco growing period.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"12\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTreatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSWC (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003epH\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eSOC(g/kg)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTN (g/kg)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eTP (g/kg)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eC-acq (umol/d/g)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eN-acq (umol/d/g)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eP-acq\u003c/p\u003e \u003cp\u003e(umol/d/g)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c10\"\u003e \u003cp\u003eMBC (mg/kg)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c11\"\u003e \u003cp\u003eMBN (mg/kg)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c12\"\u003e \u003cp\u003eMBP (mg/kg)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eR-CK\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.25\u0026thinsp;\u0026plusmn;\u0026thinsp;0.02a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.77\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e15.30\u0026thinsp;\u0026plusmn;\u0026thinsp;0.76a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.27\u0026thinsp;\u0026plusmn;\u0026thinsp;0.01a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.08\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7.72\u0026thinsp;\u0026plusmn;\u0026thinsp;0.71a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e15.64\u0026thinsp;\u0026plusmn;\u0026thinsp;1.94a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e18.88\u0026thinsp;\u0026plusmn;\u0026thinsp;1.26a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e49.97\u0026thinsp;\u0026plusmn;\u0026thinsp;1.70a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e3.11\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e1.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.29a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eR-T1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.23\u0026thinsp;\u0026plusmn;\u0026thinsp;0.01a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.90\u0026thinsp;\u0026plusmn;\u0026thinsp;0.06a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e17.83\u0026thinsp;\u0026plusmn;\u0026thinsp;1.47a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.47\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.21\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e6.09\u0026thinsp;\u0026plusmn;\u0026thinsp;0.86a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e17.95\u0026thinsp;\u0026plusmn;\u0026thinsp;1.12a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e18.00\u0026thinsp;\u0026plusmn;\u0026thinsp;1.65a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e72.68\u0026thinsp;\u0026plusmn;\u0026thinsp;5.64a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e5.48\u0026thinsp;\u0026plusmn;\u0026thinsp;1.89a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e2.90\u0026thinsp;\u0026plusmn;\u0026thinsp;1.08a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eR-T2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.27\u0026thinsp;\u0026plusmn;\u0026thinsp;0.02a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.15b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e15.83\u0026thinsp;\u0026plusmn;\u0026thinsp;1.03a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.33\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.10\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.75\u0026thinsp;\u0026plusmn;\u0026thinsp;0.68a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e14.86\u0026thinsp;\u0026plusmn;\u0026thinsp;1.82a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e18.15\u0026thinsp;\u0026plusmn;\u0026thinsp;1.68a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e59.07\u0026thinsp;\u0026plusmn;\u0026thinsp;5.43a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.40\u0026thinsp;\u0026plusmn;\u0026thinsp;1.26a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e1.15\u0026thinsp;\u0026plusmn;\u0026thinsp;0.30a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eR-T3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.26\u0026thinsp;\u0026plusmn;\u0026thinsp;0.02a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e7.00\u0026thinsp;\u0026plusmn;\u0026thinsp;0.00a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e15.20\u0026thinsp;\u0026plusmn;\u0026thinsp;0.46a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.32\u0026thinsp;\u0026plusmn;\u0026thinsp;0.05a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.05\u0026thinsp;\u0026plusmn;\u0026thinsp;0.06a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.58\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e17.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.92a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e18.11\u0026thinsp;\u0026plusmn;\u0026thinsp;1.85a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e53.35\u0026thinsp;\u0026plusmn;\u0026thinsp;9.69a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e2.53\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.96\u0026thinsp;\u0026plusmn;\u0026thinsp;0.31a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eF-CK\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.22\u0026thinsp;\u0026plusmn;\u0026thinsp;0.02a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.67\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e16.90\u0026thinsp;\u0026plusmn;\u0026thinsp;1.21a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.48\u0026thinsp;\u0026plusmn;\u0026thinsp;0.10a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.09\u0026thinsp;\u0026plusmn;\u0026thinsp;0.01a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7.08\u0026thinsp;\u0026plusmn;\u0026thinsp;1.39a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e15.23\u0026thinsp;\u0026plusmn;\u0026thinsp;1.72a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e21.89\u0026thinsp;\u0026plusmn;\u0026thinsp;1.62a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e68.20\u0026thinsp;\u0026plusmn;\u0026thinsp;10.57a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e7.02\u0026thinsp;\u0026plusmn;\u0026thinsp;1.65a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e1.60\u0026thinsp;\u0026plusmn;\u0026thinsp;0.39a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eF-T1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.22\u0026thinsp;\u0026plusmn;\u0026thinsp;0.02a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.83\u0026thinsp;\u0026plusmn;\u0026thinsp;0.27a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e16.43\u0026thinsp;\u0026plusmn;\u0026thinsp;0.98a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.33\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.09\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.22a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e14.73\u0026thinsp;\u0026plusmn;\u0026thinsp;1.84a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e21.60\u0026thinsp;\u0026plusmn;\u0026thinsp;1.88a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e53.92\u0026thinsp;\u0026plusmn;\u0026thinsp;1.50a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1.53\u0026thinsp;\u0026plusmn;\u0026thinsp;0.49a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e3.52\u0026thinsp;\u0026plusmn;\u0026thinsp;0.70a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eF-T2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.25\u0026thinsp;\u0026plusmn;\u0026thinsp;0.01a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.73\u0026thinsp;\u0026plusmn;\u0026thinsp;0.20a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e15.87\u0026thinsp;\u0026plusmn;\u0026thinsp;0.66a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.37\u0026thinsp;\u0026plusmn;\u0026thinsp;0.04a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e 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colname=\"c4\"\u003e \u003cp\u003e16.70\u0026thinsp;\u0026plusmn;\u0026thinsp;0.65a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.46\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.22\u0026thinsp;\u0026plusmn;\u0026thinsp;0.02a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e9.65\u0026thinsp;\u0026plusmn;\u0026thinsp;0.21a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e15.45\u0026thinsp;\u0026plusmn;\u0026thinsp;2.58a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e23.57\u0026thinsp;\u0026plusmn;\u0026thinsp;1.15a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e68.47\u0026thinsp;\u0026plusmn;\u0026thinsp;5.45a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e6.57\u0026thinsp;\u0026plusmn;\u0026thinsp;0.66ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e5.41\u0026thinsp;\u0026plusmn;\u0026thinsp;2.20a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eH-T3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.11\u0026thinsp;\u0026plusmn;\u0026thinsp;0.01a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6.47\u0026thinsp;\u0026plusmn;\u0026thinsp;0.13a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e14.97\u0026thinsp;\u0026plusmn;\u0026thinsp;0.57a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.33\u0026thinsp;\u0026plusmn;\u0026thinsp;0.03a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.14\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e6.77\u0026thinsp;\u0026plusmn;\u0026thinsp;0.14b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e16.57\u0026thinsp;\u0026plusmn;\u0026thinsp;1.892a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e22.86\u0026thinsp;\u0026plusmn;\u0026thinsp;0.37a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e70.95\u0026thinsp;\u0026plusmn;\u0026thinsp;7.21a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e9.01\u0026thinsp;\u0026plusmn;\u0026thinsp;1.44a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e3.62\u0026thinsp;\u0026plusmn;\u0026thinsp;0.33a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"12\"\u003eNotes: SWC, soil water content; pH, soil pH; SOC, soil organic carbon; TN, soil total nitrogen; TP, soil total phosphorus; C-acq, BG; N-acq, NAG\u0026thinsp;+\u0026thinsp;LAP; P-acq, ACP; MBC, microbial biomass C; MBN, microbial biomass N; NBP, microbial biomass P. The R, F, M, and H mean the root extending, flourishing, mature and harvest sampling period. CK, conventional fertilization; T1, conventional fertilization\u0026thinsp;+\u0026thinsp;microbial fertilizer; T2, 75% conventional fertilization\u0026thinsp;+\u0026thinsp;microbial fertilizer; T3, microbial fertilizer. Values are means\u0026thinsp;\u0026plusmn;\u0026thinsp;standard error (n\u0026thinsp;=\u0026thinsp;3). Lowercase letters indicate significant differences among different fertilizer treatments for each growing period, respectively (TukeyHSD test, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eDifferent sampling time and different fertilization treatments had no significant effect on soil microbial biomass and soil resources (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05), which indicates that soil homeostasis was always strictly homeostatic among different fertilization treatments in the same period (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The above results showed that the soil microbial stoichiometric ratios are not affected by soil resources.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eHomeostasis coefficients of soil microbial biomass and their stoichiometry.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSampling Time\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eVariable(x)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eVariable(y)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1/H\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eR\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eP\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eGrade\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"5\" rowspan=\"6\"\u003e \u003cp\u003eR\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSOC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMBC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.408\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.079\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.375\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMBN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.926\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.020\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.660\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMBP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-20.000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.240\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.106\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003esC/N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003emC/N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.078\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.268\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.268\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003esC/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003emC/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.091\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.228\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.228\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003esN/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003emN/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.671\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.238\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.238\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"5\" rowspan=\"6\"\u003e \u003cp\u003eF\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSOC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMBC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.341\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.036\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.553\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMBN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.757\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.037\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.548\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMBP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.328\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.030\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.593\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003esC/N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003emC/N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-0.175\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.142\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.227\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003esC/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003emC/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.092\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.105\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.303\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003esN/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003emN/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.545\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.955\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"5\" rowspan=\"6\"\u003e \u003cp\u003eM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSOC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMBC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.599\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.032\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.577\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMBN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.210\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.002\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.903\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMBP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.545\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.312\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.059\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003esC/N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003emC/N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-0.397\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.049\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.489\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003esC/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003emC/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.977\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.017\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.687\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003esN/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003emN/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-1.530\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.064\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.428\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"5\" rowspan=\"6\"\u003e \u003cp\u003eH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSOC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMBC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.215\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.003\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.871\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMBN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.613\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.003\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.877\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMBP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.704\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.000\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.999\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003esC/N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003emC/N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.180\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.814\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003esC/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003emC/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.169\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.052\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.477\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003esN/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003emN/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.565\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e0.145\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.223\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003estrictly homeostatic\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"8\"\u003eNotes: 1/H is the slope of the regression line between ln (y) and ln (x), where x is the soil resource stoichiometric ratio (e.g.sC/N), y is the microbial biomass carbon, nitrogen, and phosphorus stoichiometric ratio (e.g. mC/N). The regression relationship was not significant (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05) in this study, so the microbial stoichiometry was considered to be \"strictlyhomeostatic\". The R, F, M, and H mean the root extending, flourishing, mature, and harvest sampling period. SOC, soil organic carbon; TN, soil total nitrogen; TP, soil total phosphorus; MBC, microbial biomass C; MBN, microbial biomass N; MBP, microbial biomass P; sC/N, SOC/TN; sC/P, SOC/TP; sN/P, TN/TP; mC/N, MBC/MBN; mC/P, MBC/MBP;mN/P, MBN/MBP.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eSoil C, N, and P cycle-related enzyme activities and microbial resource limitations.\u003c/b\u003e The C-acq/MBC, N-acq/MBN, and P-acq/MBP were all significantly affected by sampling time, at the same time, the C-acq/MBC and N-acq/MBN were also affected by the interaction of sampling times and fertilization treatments (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The C-acq/MBC was significantly higher in T3 treatment at the M period of flue-cured tobacco (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA). N-acq/MBN was significantly higher in the T1 treatment than in the other treatments at F period (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB). The ratios of N-acq/MBN and P-acq/MBP decreased as the flue-cured tobacco entered the H period (Figs.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB and \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eC).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe vector angle of the four treatments at different sampling times (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) was almost higher than 45\u0026deg;, and first increased then tended to be stable in the order of T1\u0026thinsp;\u0026gt;\u0026thinsp;T2\u0026thinsp;\u0026gt;\u0026thinsp;CK\u0026thinsp;\u0026gt;\u0026thinsp;T3 in the M and H periods (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eA). On the other hand, almost all the soil enzyme stoichiometry points, except for the samples from the R period, at the whole growth period, were above the 1:1 line (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eB), indicating that the sample is P limited except for the N limitation at the R period. All soils were not limited by C and N co-limitation or C and P co-limitation (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eC). What's more, the linear regression analysis as shown in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e resulted that the soil vector angle, which almost indicated the phosphorous limitation in this study, were decreased with increasing SWC, pH, MBC, and mC/P (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eLinear regression of soil physicochemical and microbial indicators with vector angles\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariables(x)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eregression equation\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eR square\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSWC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;59.2-39.8x\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003epH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;91.4-5.97x\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.005\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSOC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;56.2-0.28x\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.556\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;54.7-2.14x\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.741\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;56.5-4.19x\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.585\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMBC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;57.9-0.114x\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.006\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMBN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;51.6\u0026thinsp;+\u0026thinsp;0.0553x\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.839\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMBP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;50.5\u0026thinsp;+\u0026thinsp;0.459x\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.164\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSCN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;57.5-0.479x\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.590\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSCP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;52.1-0.0177x\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.974\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSNP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;49.5\u0026thinsp;+\u0026thinsp;1.96x\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.772\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003emC/N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;53.4-0.1x\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.11\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003emC/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;54.2-0.0778x\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.18\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003emN/P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ey\u0026thinsp;=\u0026thinsp;53.3-0.62x\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.064\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eNotes: SWC, soil water content; pH, soil pH; SOC, soil organic carbon; TN, soil total nitrogen; TP, soil total phosphorus; C-acq, BG; N-acq, NAG\u0026thinsp;+\u0026thinsp;LAP; P-acq, ACP; MBC, microbial biomass C; MBN, microbial biomass N; MBP, microbial biomass P.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eCorrelation of soil, soil microbial biomass and enzyme-related C, N and P stoichiometric ratios.\u003c/b\u003e The principal component analysis results showed that axes 1 and 2 explained 25.8% and 24.0% of the variation in the soil resources, microbial biomass, and enzyme stoichiometry. The differences in soil and microbial C, N, and P indexes in different sampling times were greater than the differences between different fertilization treatments (Figs.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eA and \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eB). The differences in the R and F periods were higher than that in M and H periods (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eA). The correlation analysis results further showed that there was no significant relationship between mC/N and sC/N, mC/P and sC/P, and mN/P and sN/P. However, the soil eC/P and eC/N, mC/P and mN/P, sC/P, and sC/N were positively correlated. At the same time, significant negative correlations were found between mC/N and eC/N, mC/N and mN/P, and sN/P and sC/N. Soil organic carbon, total nitrogen, and total phosphorus were significantly positively correlated, as well as significant positive correlations between MBC and SOC, MBN and TN, and MBP and TP (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eC).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe stoichiometric balance of soil resources is very critical for maintaining microbial metabolism and elemental dynamic balance, which can reflect the ability of microorganisms to decompose soil organic matter and release phosphorus, indicate the supply of soil nutrients during plant growth\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e,\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e,\u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e50\u003c/span\u003e\u003c/sup\u003e. Consistent with the results of previous studies, the soil SOC, TN, and TP content in this study were significantly positive correlated (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eC, p\u0026thinsp;\u0026lt;\u0026thinsp;0.05), and there was a good interaction between SOC, TN, and TP\u003csup\u003e\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e,\u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e\u003c/sup\u003e. Meanwhile, Tian et al.\u003csup\u003e\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u003c/sup\u003e showed that the mean values of soil C/N, C/P, and N/P were 11.9, 61, and 5.2 in China, respectively. The average C/N value (11.45) in this study was similar to the above-average value, considering that carbon is a structural element, and its accumulation and consumption processes are relatively steady\u003csup\u003e\u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e52\u003c/span\u003e\u003c/sup\u003e. The variability of soil C/N in different fertilization treatments among different sampling times is not significant in this study. Meanwhile, the average values of C/P and N/P were 14.1 and 1.2 in this study and were lower than the average value of soil in China, which may be due to the low organic carbon content in red soil in this study\u003csup\u003e\u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e53\u003c/span\u003e\u003c/sup\u003e; or the lower pH, the lower nitrogen availability\u003csup\u003e\u003cspan citationid=\"CR54\" class=\"CitationRef\"\u003e54\u003c/span\u003e\u003c/sup\u003e. However, the addition of microbial fertilizer improved the value of soil C/P and N/P in the H period (Figs.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eB and \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eC), which may be because \u003cem\u003eBacillus subtilis\u003c/em\u003e contained in the microbial fertilizer can improve soil nitrogen fixation capacity and increase soil organic carbon content\u003csup\u003e\u003cspan citationid=\"CR55\" class=\"CitationRef\"\u003e55\u003c/span\u003e\u003c/sup\u003e; or \u003cem\u003eBacillus mucilaginosus\u003c/em\u003e can decompose soil silicate minerals, and convert insoluble substances such as potassium, phosphorus, and silicon into soluble substances that can be used for plant growth\u003csup\u003e\u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e56\u003c/span\u003e\u003c/sup\u003e. Interestingly, the reduced usage of compound fertilizer combined with microbial fertilizer (T2) in this study was more obvious for increasing soil C/P and N/P (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eB and \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eC).\u003c/p\u003e \u003cp\u003eMicrobial resource limitation specifies that microbial growth and activity are often limited by nutrient availability and energy \u003csup\u003e\u003cspan citationid=\"CR57\" class=\"CitationRef\"\u003e57\u003c/span\u003e\u003c/sup\u003e. Ecological stoichiometry theory suggests that the C:N:P ratio of soil microbial biomass is more stable relative to the soil C, N, and P stoichiometry ratio and reflects the state of microbial C, N, and P demand\u003csup\u003e\u003cspan citationid=\"CR58\" class=\"CitationRef\"\u003e58\u003c/span\u003e\u003c/sup\u003e. Our results indicated that there was no significant correlation between microbial biomass stoichiometric ratio and soil resources stoichiometric ratio (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eC). The strict homeostasis of soil microbial biomass in different fertilizations among different sampling times also confirmed that the stability of microbial stoichiometry\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Moreover, the global average value of C/N, C/P, and N/P of soil microbial biomass was 7.6, 42.4, and 5.6, respectively\u003csup\u003e\u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e\u003c/sup\u003e. The MBC/MBP and MBN/MBP were 30.52 and 2.37 in this study, which was lower than the global level. This result indicated that soil microorganisms had a weak tendency to assimilate soil available P, and the ability to absorb phosphorus was a weak result of the competition with plants\u003csup\u003e\u003cspan citationid=\"CR59\" class=\"CitationRef\"\u003e59\u003c/span\u003e\u003c/sup\u003e. However, the MBC/MBN (19.14) was higher than the global level, which suggested the relative strong nitrogen fixation ability of soil microorganisms in this study \u003csup\u003e\u003cspan citationid=\"CR60\" class=\"CitationRef\"\u003e60\u003c/span\u003e\u003c/sup\u003e. Consistently with previous studies\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e, the MBC/MBN is relatively stable in this study, and MBC/MBP and MBN/MBP varied more among different sampling periods (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA), indicating greater stoichiometric plasticity of microbial phosphorus\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e. In contrast to the previous study, Qi et al. \u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e showed that soil MBC/MBP and MBN/MBP reached the maximum in the middle and late stages of forest vegetation growth (August). Our results showed that MBC/MBP and MBN/MBP were highest in the R period, and lower in M and H periods, which may be related to different ecosystem types and soil types\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003ePrevious studies have indicated that the ratio of global soil C, N, and P-related enzyme activities is 1:1:1\u003csup\u003e61\u003c/sup\u003e. When the ratio deviates from 1:1:1, it may indicate that soil microorganisms are affected by carbon, nitrogen, or phosphorus limitation\u003csup\u003e\u003cspan citationid=\"CR61\" class=\"CitationRef\"\u003e61\u003c/span\u003e\u003c/sup\u003e. The C:N:P of enzyme activities was 1:1.45:1.64 in this study, which showed that soil microorganisms are more restricted by nitrogen and phosphorus than soil carbon. In addition, enzyme stoichiometry points were almost above the 1:1 line, and the vector angles in almost all treatments were greater than 45\u0026deg;, which both showed the P-limited, except for a few points of N-limited at the R period. Moreover, the soil microorganisms changed from N-limited to P-limited with the extension of the growth period\u003csup\u003e\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e\u003c/sup\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eA). It should be noted that enzymatic stoichiometry is controversial in determining carbon resource constraints\u003csup\u003e\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e,\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u003c/sup\u003e. However, this study combined the C, N, and P enzyme stoichiometric characteristics and vector angle to determine the microbial resource limitation, and the tobacco planting soil in this study was limited by N and P, which could well avoid this bias, and the study results were very convincing. The limitation of soil N and P may be due to the acidic soil in this study. Previous research has suggested that the limitation of P is mainly due to the strong binding of Fe\u003csup\u003e3+\u003c/sup\u003e and Al\u003csup\u003e3+\u003c/sup\u003eor the water-soluble P is slowly converted into occluded phosphorus in the acid soil, resulting in the reduction of P utilization\u003csup\u003e\u003cspan citationid=\"CR62\" class=\"CitationRef\"\u003e62\u003c/span\u003e,\u003cspan citationid=\"CR63\" class=\"CitationRef\"\u003e63\u003c/span\u003e\u003c/sup\u003e. Secondly, with the extension of the growth period of flue-cured tobacco, the phosphorus limitation increased first and then decreased. The T3 treatment has an earlier weakening trend, and showed a weakening phenomenon from the F period to the M period, while the remaining treatments showed a weakening trend from M to H period. The changes in phosphorus limitation may be due to that a large amount of phosphorus is needed to supply the primary productivity of flue-cured tobacco in the vigorous growth period, thereby increasing the limitation of soil microorganisms on phosphorus\u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e, and the phosphorus limitation was alleviated by increasing the soil total phosphorus in H period\u003csup\u003e\u003cspan citationid=\"CR64\" class=\"CitationRef\"\u003e64\u003c/span\u003e\u003c/sup\u003e (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The result also showed that the full application of microbial fertilizer (T3) had a more obvious effect on alleviating phosphorus limitation, which is conducive to microbial nutrient balance by alleviating nutrient competition between soil microbial and soils.\u003c/p\u003e \u003cp\u003eMoreover, Yang et al.\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e showed that microbial nitrogen and phosphorus limitation was affected by soil nutrient stoichiometric ratio, soil water content, soil pH, soil bulk density, and soil organic C the key factor in microbial nitrogen and phosphorus limitation. At the same time, other studies have shown that temperature, soil moisture, soil pH, and SOC can affect microbial P limitation\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e,\u003cspan citationid=\"CR65\" class=\"CitationRef\"\u003e65\u003c/span\u003e\u003c/sup\u003e. In this study, soil water content, soil pH, MBC, and mC/P had negative significant effects on microbial N and P limitation (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Consistent with previous results, the higher soil water content will accelerate the decomposition of soil organic carbon\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e, and result in enhancing microbial activity and microbial biomass carbon content, the soil nutrient limitation converts from nitrogen limitation to phosphorus limitation\u003csup\u003e\u003cspan citationid=\"CR66\" class=\"CitationRef\"\u003e66\u003c/span\u003e\u003c/sup\u003e. On the other hand, low soil pH, and mC/P can lead to reduced availability of P in soil, microorganisms also compete with plants for P, and biological fixation of P occurs, thereby aggravating P limitation\u003csup\u003e\u003cspan citationid=\"CR62\" class=\"CitationRef\"\u003e62\u003c/span\u003e,\u003cspan citationid=\"CR65\" class=\"CitationRef\"\u003e65\u003c/span\u003e\u003c/sup\u003e. In this study, soil water content, soil pH, and soil m C/P were decreased with the extension of the growth period, which may result in the weakening of phosphorus limitation in the H period (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eSoil resources, microbial biomass, enzyme activities, and stoichiometric ratios were generally more affected by sampling times than by fertilization treatments. The stoichiometric ratio of microbial C, N, and P was strict homeostasis and is not affected by the changes in soil C, N, and P stoichiometric ratio. While the soil microbial metabolism in tobacco-growing soils among different growth periods is more susceptible to phosphorus restriction, soil water content, soil pH, MBC and mC/P are the key factors to influence phosphorus limitation. We also found that the addition of microbial fertilizers can change the biophysical and chemical properties of the soil, and then affect the stoichiometric balance and microbial nutrients, effectively reducing the phosphorus limitation in this study, and the reduction effect is more obvious in the mature and harvest periods. This study links soil physicochemical properties with soil microbial metabolic limitations, which is beneficial to deepen our understanding of soil nutrient cycling mechanisms.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eData availability\u003c/p\u003e\n\u003cp\u003eAll data generated and analyzed during this study are included in this published article.\u003c/p\u003e\n\u003cp\u003eAcknowledgements\u003c/p\u003e\n\u003cp\u003eThis study was financially supported by the Scientific Research Foundation Project of the Yunnan Education Department (2022Y695), the Basic Research Joint Special Youth Project of Local Undergraduate Universities in Yunnan Province (2019FH001-098, 202101BA070001-057), and the College Students\u0026apos; innovation and entrepreneurship training program (S202211393048).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAuthor contributions statement\u003c/p\u003e\n\u003cp\u003eConceptualization, Z, T. Data curation, J.F., T.X., Y.R., X.S. and L.C. Formal analysis, J.F. L.C. and Z, T. Funding acquisition, J.F., Y.Z. and Z,T. Investigation, T.X., Y.R., X.S. and Y.Z. Resources, X.S., T.W. and X.S. Writing-original draft, J.F. Writing-review \u0026amp; editing, J.F., T.X., Y.R., X.S., T.W., X.S., Y.Z., L. C. and Z. T.All authors reviewed the manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eCompeting interests\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eGao, D. \u003cem\u003eet al.\u003c/em\u003e Three‐dimensional mapping of carbon, nitrogen, and phosphorus in soil microbial biomass and their stoichiometry at the global scale.\u003cem\u003e Global Change Biology\u003c/em\u003e. (2022)\u003c/li\u003e\n\u003cli\u003eCui, J. \u003cem\u003eet al\u003c/em\u003e. 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In this study, we studied the effect of compound fertilizers combined with microbial fertilizer treatments on stoichiometric characteristics of rhizosphere soil and the limitation of microbial resources during the flue-cured tobacco growth periods. The results indicated that soil and microbial C:N:P varied greatly with the growing period, the effect of sampling time was usually greater than fertilization treatment, and the microbial C: N:P did not vary with the soil resource stoichiometric ratios. With the extension of the growth period, the microbial metabolism of tobacco-growing soil was limited by phosphorus and showed a trend of increasing first and then decreasing. The rhizosphere soil microbial resources nitrogen and phosphorus limitation were mainly affected by soil water content, soil pH, microbial biomass carbon, and the ratio of microbial biomass carbon to microbial biomass phosphorus, and the application of microbial fertilizers can reduce phosphorus limitation. Therefore, the application of microbial fertilizers regulates the limitation of microbial resources by affecting the soil and microbial biomass C: N: P in flue-cured tobacco rhizosphere soils.\u003c/p\u003e","manuscriptTitle":"Microbial fertilizer regulates C:N:P stoichiometry and alleviates phosphorus limitation in flue-cured tobacco planting soil","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2022-11-29 18:59:02","doi":"10.21203/rs.3.rs-2145253/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2023-05-19T01:06:53+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2023-04-29T14:37:22+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"5764ce9d-551f-4afc-8ee3-2bb92063d620","date":"2023-01-28T09:48:47+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"2bcf044e-c59f-41bb-9fda-246d85155538","date":"2022-12-30T05:21:28+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2022-12-27T08:20:38+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2022-12-27T07:18:54+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2022-11-25T09:29:54+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2022-11-25T09:26:14+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2022-10-08T12:52:15+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"73fcc897-1457-4ba6-8c89-71efb9fd9afa","owner":[],"postedDate":"November 29th, 2022","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2023-10-16T21:27:57+00:00","versionOfRecord":{"articleIdentity":"rs-2145253","link":"https://doi.org/10.1038/s41598-023-37438-w","journal":{"identity":"scientific-reports","isVorOnly":false,"title":"Scientific Reports"},"publishedOn":"2023-06-24 21:17:06","publishedOnDateReadable":"June 24th, 2023"},"versionCreatedAt":"2022-11-29 18:59:02","video":"","vorDoi":"10.1038/s41598-023-37438-w","vorDoiUrl":"https://doi.org/10.1038/s41598-023-37438-w","workflowStages":[]},"version":"v1","identity":"rs-2145253","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-2145253","identity":"rs-2145253","version":["v1"]},"buildId":"re_ckhLnmML6MCF96OHNJ","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}