Willow woodchip incorporation moderates soil carbon and nitrogen losses in a potato production system in Atlantic Canada

Willow woodchip incorporation moderates soil carbon and nitrogen losses in a potato production system in Atlantic Canada | 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 Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Short Report Willow woodchip incorporation moderates soil carbon and nitrogen losses in a potato production system in Atlantic Canada Louis-Pierre Comeau, Sheng Li, Yefang Jiang, Kyle MacKinley, Yulia Kupriyanovich This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7456686/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 10 You are reading this latest preprint version Abstract Maintaining soil organic carbon (SOC) in intensively managed potato systems is challenging due to frequent tillage and low residue return. A field experiment was conducted from 2019 to 2024 at the Agriculture and Agri-Food Canada Fredericton Research and Development Centre, New Brunswick, Canada, to evaluate the effects of willow (Salix spp.) woodchip incorporation on SOC, soil organic nitrogen (SON), and soil properties. Willow chips harvested from a local plantation were incorporated into the topsoil (0–30 cm) at a rate of 40 Mg ha⁻¹ in fall 2019. Surface soils (0–15 cm) were sampled annually and analyzed for SOC, SON, pH, and nutrients. SOC and SON stocks declined over time in both treatments, but losses were consistently smaller under woodchip incorporation. By 2023, SOC in amended plots was approximately 0.06 kg C m⁻² higher than in the control. SON declines were also slightly slower in the amended plots, while soil pH and most nutrient levels were unaffected. These findings suggest that woodchip incorporation may modestly reduce the rate of SOC and SON decline in potato-based systems, but the effect appears limited in magnitude and duration. Potato production Soil organic carbon Woodchip amendment Soil organic nitrogen Residue management Atlantic Canada Figures Figure 1 Figure 2 Introduction Soil organic carbon (SOC) is a key indicator of soil health and sustainability (Lal, 2004 ; Six et al., 2002 ). Intensive potato production systems are prone to SOC depletion due to frequent tillage, short rotations, and low residue return (Chen et al., 2024 ; Nyiraneza et al., 2017 ). Organic amendments, including composts and manures, are commonly used to mitigate SOC decline, but coarse woody residues such as woodchips are less studied, despite their local availability from forestry and land-clearing operations (Hangs et al., 2016 ; DeLuca & Aplet, 2008 ). High C:N ratio residues can slow mineralization, potentially contributing to SOC retention in surface soil (Poeplau & Don, 2015 ). However, their impacts on nutrient dynamics and crop viability in potato rotations remain unclear. Here, we report results from a five-year field study evaluating the effects of woodchip incorporation on SOC, SON, and soil properties. This study aimed to assess how woodchip incorporation influences surface soil carbon and nitrogen in potato rotations, a management system where organic matter depletion is a persistent challenge. Materials and Methods The experiment was conducted from 2019 to 2024 at the Agriculture and Agri-Food Canada Fredericton Research and Development Centre, New Brunswick, Canada (45°52′ N, 66°31′ W). The soil is classified as a sandy loam Rustic Podzol (Driscoll et al., 2025 ). The trial consisted of eight plots (10 × 10 m each) arranged in a completely randomized design with two treatments: (i) unamended control and (ii) willow woodchip incorporation, each replicated four times. Willow (Salix spp.) stems harvested from an AAFC plantation at Havelock, New Brunswick, were chipped and applied at 40 Mg ha⁻¹ (4 kg m⁻²) following potato harvest in fall 2019. Chips were incorporated into the top soil with a disk implement. Soil cores (0–15 cm) were collected annually after harvest from 2019 to 2024. Bulk density was measured on intact cores. SOC and SON were analyzed by dry combustion using an Elementar Vario Max CN analyzer (Comeau et al., 2022 ). Soil pH was measured in a 1:1 soil:water suspension (Hendershot et al., 2007 ). Available nutrients (P, K, Ca, Mg, Na) were determined using the Mehlich 3 extraction. Cation exchange capacity (CEC) was also calculated. SOC and SON stocks were calculated using the fixed-depth approach. Data were analyzed by ANOVA with year, treatment, and their interaction as fixed factors, and significance was declared at p < 0.05. Results The SOC stocks in the 0–15 cm layer declined over time in both treatments, but losses were greater in the control (Fig. 1 ). By 2023, the cumulative decline was approximately − 0.2 kg C m⁻² in the control compared with − 0.1 kg C m⁻² in the woodchip treatment. Regression slopes indicated a slower decline in amended plots (–0.057 kg C m⁻² yr⁻¹) relative to the control (–0.061 kg C m⁻² yr⁻¹). The SON stocks also declined across all plots (Fig. 2 ). The control showed a steeper decline (–0.0092 kg N m⁻² yr⁻¹) compared with the woodchip treatment (–0.0077 kg N m⁻² yr⁻¹). By 2024, both treatments converged near 0.1 kg N m⁻², though the amended plots consistently retained slightly more N. Woodchip addition had minimal effects on most soil chemical properties (Table 1 ). Soil pH remained stable at 5.5–5.8 across treatments. Potassium was slightly higher in woodchip plots (192–216 ppm) than in controls (160–202 ppm), while phosphate, calcium, magnesium, sodium, and CEC showed no consistent differences. Table 1 Soil properties for control and woodchips treatments over three years (2020–2022). Soil Property Treatment 2020 2021 2022 pH (H₂O 1:1) Control 5.6 (0.1) 5.5 (0.1) 5.8 (0.1) Woodchips 5.8 (0.1) 5.6 (0.1) 5.8 (0.1) Phosphate (P₂O₅, ppm) Control 134.3 (7.8) 152.3 (17.6) 118.3 (6.0) Woodchips 122.0 (1.5) 116.5 (7.4) 111.8 (5.2) Potash (K₂O, ppm) Control 202.5 (5.5) 160.5 (6.6) 201.0 (10.7) Woodchips 216.5 (8.0) 192.5 (16.3) 213.5 (12.2) Magnesium (Mg, ppm) Control 220.3 (5.9) 201.3 (7.9) 201.0 (3.7) Woodchips 218.5 (7.1) 219.0 (10.5) 211.3 (11.0) Calcium (Ca, ppm) Control 970.0 (46.7) 741.3 (35.9) 947.8 (46.7) Woodchips 1005.5 (54.2) 796.3 (70.4) 1028.3 (62.2) Sodium (Na, ppm) Control 21.0 (0.6) 12.8 (2.8) 21.3 (1.7) Woodchips 19.5 (1.3) 13.3 (2.7) 22.8 (3.1) CEC (Meq/100 g) Control 12.3 (0.3) 11.5 (0.3) 13.3 (0.3) Woodchips 11.3 (0.8) 10.8 (0.3) 13.5 (0.3) Values in parentheses represent standard errors. CEC, Cation Exchange Capacity Discussion Woodchip incorporation increased SOC and SON in the surface layer, consistent with expectations for high-C inputs (Grandy et al., 2006 ; Poeplau & Don, 2015 ). Overall, our results indicate that incorporating willow woodchips at 40 Mg ha⁻¹ can slow, but not eliminate, SOC and SON declines in potato-based systems. The observed differences were relatively small (~ 0.06 kg C m⁻² over five years) and appear to be transient, suggesting that single applications of coarse woody residues are unlikely to provide lasting protection against soil organic matter losses. Furthermore, the study was restricted to the 0–15 cm soil layer and did not assess yield responses or deeper profile changes, which limits the scope of interpretation. Taken together, these findings suggest that while woodchip incorporation may offer incremental benefits, broader soil management strategies such as repeated applications, complementary organic amendments, or diversification of crop rotations will likely be required to achieve SOC improvements. Conclusion Willow woodchip incorporation at 40 Mg ha⁻¹ slowed, but did not prevent, SOC and SON losses in a potato-based cropping system at Fredericton, New Brunswick. The study was limited to the surface 0–15 cm, without assessments of deeper soil layers or crop yield responses, and therefore results should be interpreted with these constraints in mind. The differences between treatments were modest (~ 0.06 kg C m⁻² over five years), indicating only a limited benefit for mitigating soil organic matter depletion. These findings suggest that coarse woody residues may modestly reduce the rate of SOC and SON decline in intensively managed systems, but the effect appears temporary and limited in magnitude. Additional management practices, including complementary organic amendments, crop diversification, or reduced tillage, will likely be required to achieve long-term SOC stabilization and nutrient retention. Declarations Acknowledgments We acknowledge that this research was conducted on the traditional and unceded territory of the Maliseet and Mi’kmaq Peoples. We appreciate the field and laboratory help from Medison White and Kayli McGarrigle. This work was supported by funding from Agriculture and Agri-Food Canada (grant J-001754.001.03 and grant J-002391.001.08). During the preparation of this work the authors used ChatGPT (OpenAI) in order to assist with English grammar corrections, improvements in syntax, and occasional translations. After using this tool, the authors carefully reviewed and edited the content as needed and take full responsibility for the content of the publication. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Clinical trial number not applicable. Ethics, Consent to Participate, and Consent to Publish declarations not applicable. L.-P.C. designed and conducted the experiment, performed the analyses, and wrote the main manuscript text. K.M. and Y.K. carried out field sampling and laboratory analyses. S.L. and Y.J. served as project leaders, secured funding, coordinated the study, and provided critical revisions to the manuscript. Declarations of data Availability The datasets generated and analyzed during the current study are available from the corresponding author on reasonable request. References Chen, D., Barrett, R., Mimee, B. 2024. Prevalence of Verticillium spp. and Pratylenchus spp. in commercial potato fields in Atlantic Canada. American Journal of Potato Research 101, 291–305. https://doi.org/10.1007/s12230-024-09957-3 Comeau, L.-P., Goyer, C., Wagg, C., Unc, A. 2022. Ex situ soil respiration assessment using minimally disturbed microcosms and dried–sieved soils; comparison of methods to assess soil health. Canadian Journal of Soil Science 102(2), 221–234. https://doi.org/10.1139/cjss-2021-0143 DeLuca, T.H., Aplet, G.H. 2008. Charcoal and carbon storage in forest soils of the Rocky Mountain West. Frontiers in Ecology and the Environment 6(1), 18–24. https://doi.org/10.1890/070070 Driscoll, B.A., Krzic, M., Comeau, L.-P., Eskelson, B.N.I., Li, S. 2023. Short-term response of soil aggregate stability and labile carbon to contour tillage, diversion terrace, grassed waterway, and tile drainage implementation. Canadian Journal of Soil Science 103(3), 394–405. https://doi.org/10.1139/cjss-2022-0094 Driscoll, B.A., Krzic, M., Comeau, L.-P., Eskelson, B.N.I., Li, S. 2025. Response of CO₂, N₂O, and CH₄ fluxes to contour tillage, diversion terrace, grassed waterway, and tile drainage implementation. Frontiers in Soil Science 5, 1453324. https://doi.org/10.3389/fsoil.2025.1453324 Grandy, A.S., Robertson, G.P., Thelen, K.D. 2006. Do productivity and environmental trade-offs justify periodically cultivating no-till cropping systems? Agronomy Journal 98(6), 1377–1383. https://doi.org/10.2134/agronj2006.0137 Hangs, R.D., Ahmed, H.P., Schoenau, J.J. 2016. Influence of wood biochar amendments on soil nitrogen dynamics and greenhouse gas emissions in two contrasting soils. BioEnergy Research 9, 157–171. https://doi.org/10.1007/s12155-015-9671-5 Hendershot, W.H., Lalande, H., Duquette, M. 2007. Soil reaction and exchangeable acidity. In: Carter, M.R., Gregorich, E.G. (eds.) Soil Sampling and Methods of Analysis, 2nd edn. CRC Press, Boca Raton, FL, pp. 173–178. Lal, R. 2004. Soil carbon sequestration impacts on global climate change and food security. Geoderma 123(1–2), 1–22. https://doi.org/10.1016/j.geoderma.2004.01.032 Nyiraneza, J., Thompson, B., Geng, X., He, J., Jiang, Y., Fillmore, S., Stiles, K. 2017. Changes in soil organic matter over 18 yr in Prince Edward Island, Canada. Canadian Journal of Soil Science 97, 745–756. https://doi.org/10.1139/cjss-2017-0033 Poeplau, C., Don, A. 2015. Carbon sequestration in agricultural soils via cultivation of cover crops – a meta-analysis. Agriculture, Ecosystems & Environment 200, 33–41. https://doi.org/10.1016/j.agee.2014.10.024 Six, J., Conant, R.T., Paul, E.A., Paustian, K. 2002. Stabilization mechanisms of soil organic matter: implications for C-saturation of soils. Plant and Soil 241(2), 155–176. https://doi.org/10.1023/A:1016125726789 Tisdall, J.M., Oades, J.M. 1982. Organic matter and water-stable aggregates in soils. Journal of Soil Science 33(2), 141–163. https://doi.org/10.1111/j.1365-2389.1982.tb01755.x Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 25 Dec, 2025 Reviews received at journal 17 Dec, 2025 Reviewers agreed at journal 11 Dec, 2025 Reviewers agreed at journal 09 Dec, 2025 Reviews received at journal 26 Nov, 2025 Reviewers agreed at journal 25 Nov, 2025 Reviewers invited by journal 11 Nov, 2025 Editor assigned by journal 29 Oct, 2025 Submission checks completed at journal 21 Sep, 2025 First submitted to journal 21 Sep, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Centre.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-7456686/v1/83a14064747a8c51c977ac3a.png"},{"id":96502087,"identity":"51b036ac-cc84-4b70-b6bb-9bb2f6b25d07","added_by":"auto","created_at":"2025-11-22 00:36:13","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":26154,"visible":true,"origin":"","legend":"\u003cp\u003eChange in soil organic nitrogen (SON) stock (kg N m², 0–15 cm) from 2019 to 2024 under control (no woodchips) and woodchip treatment at the AAFC Fredericton Research and Development Centre.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-7456686/v1/3eb68006ea9aee50296921d3.png"},{"id":96913407,"identity":"e6d946b2-6d16-4bbf-9808-6f6d2bed6676","added_by":"auto","created_at":"2025-11-27 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Intensive potato production systems are prone to SOC depletion due to frequent tillage, short rotations, and low residue return (Chen et al., \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Nyiraneza et al., \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). Organic amendments, including composts and manures, are commonly used to mitigate SOC decline, but coarse woody residues such as woodchips are less studied, despite their local availability from forestry and land-clearing operations (Hangs et al., \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; DeLuca \u0026amp; Aplet, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2008\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eHigh C:N ratio residues can slow mineralization, potentially contributing to SOC retention in surface soil (Poeplau \u0026amp; Don, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). However, their impacts on nutrient dynamics and crop viability in potato rotations remain unclear. Here, we report results from a five-year field study evaluating the effects of woodchip incorporation on SOC, SON, and soil properties.\u003c/p\u003e\u003cp\u003eThis study aimed to assess how woodchip incorporation influences surface soil carbon and nitrogen in potato rotations, a management system where organic matter depletion is a persistent challenge.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003eThe experiment was conducted from 2019 to 2024 at the Agriculture and Agri-Food Canada Fredericton Research and Development Centre, New Brunswick, Canada (45\u0026deg;52\u0026prime; N, 66\u0026deg;31\u0026prime; W). The soil is classified as a sandy loam Rustic Podzol (Driscoll et al., \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2025\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe trial consisted of eight plots (10 \u0026times; 10 m each) arranged in a completely randomized design with two treatments: (i) unamended control and (ii) willow woodchip incorporation, each replicated four times. Willow (Salix spp.) stems harvested from an AAFC plantation at Havelock, New Brunswick, were chipped and applied at 40 Mg ha⁻\u0026sup1; (4 kg m⁻\u0026sup2;) following potato harvest in fall 2019. Chips were incorporated into the top soil with a disk implement.\u003c/p\u003e\u003cp\u003eSoil cores (0\u0026ndash;15 cm) were collected annually after harvest from 2019 to 2024. Bulk density was measured on intact cores. SOC and SON were analyzed by dry combustion using an Elementar Vario Max CN analyzer (Comeau et al., \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Soil pH was measured in a 1:1 soil:water suspension (Hendershot et al., \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2007\u003c/span\u003e). Available nutrients (P, K, Ca, Mg, Na) were determined using the Mehlich 3 extraction. Cation exchange capacity (CEC) was also calculated. SOC and SON stocks were calculated using the fixed-depth approach. Data were analyzed by ANOVA with year, treatment, and their interaction as fixed factors, and significance was declared at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThe SOC stocks in the 0\u0026ndash;15 cm layer declined over time in both treatments, but losses were greater in the control (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). By 2023, the cumulative decline was approximately \u0026minus;\u0026thinsp;0.2 kg C m⁻\u0026sup2; in the control compared with \u0026minus;\u0026thinsp;0.1 kg C m⁻\u0026sup2; in the woodchip treatment. Regression slopes indicated a slower decline in amended plots (\u0026ndash;0.057 kg C m⁻\u0026sup2; yr⁻\u0026sup1;) relative to the control (\u0026ndash;0.061 kg C m⁻\u0026sup2; yr⁻\u0026sup1;).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe SON stocks also declined across all plots (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The control showed a steeper decline (\u0026ndash;0.0092 kg N m⁻\u0026sup2; yr⁻\u0026sup1;) compared with the woodchip treatment (\u0026ndash;0.0077 kg N m⁻\u0026sup2; yr⁻\u0026sup1;). By 2024, both treatments converged near 0.1 kg N m⁻\u0026sup2;, though the amended plots consistently retained slightly more N.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eWoodchip addition had minimal effects on most soil chemical properties (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Soil pH remained stable at 5.5\u0026ndash;5.8 across treatments. Potassium was slightly higher in woodchip plots (192\u0026ndash;216 ppm) than in controls (160\u0026ndash;202 ppm), while phosphate, calcium, magnesium, sodium, and CEC showed no consistent differences.\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\u003eSoil properties for control and woodchips treatments over three years (2020\u0026ndash;2022).\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\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=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSoil Property\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTreatment\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2020\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2021\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e2022\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003epH (H₂O 1:1)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eControl\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e5.6 (0.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e5.5 (0.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e5.8 (0.1)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWoodchips\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e5.8 (0.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e5.6 (0.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e5.8 (0.1)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePhosphate (P₂O₅, ppm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eControl\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e134.3 (7.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e152.3 (17.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e118.3 (6.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWoodchips\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e122.0 (1.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e116.5 (7.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e111.8 (5.2)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003ePotash (K₂O, ppm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eControl\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e202.5 (5.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e160.5 (6.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e201.0 (10.7)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWoodchips\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e216.5 (8.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e192.5 (16.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e213.5 (12.2)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eMagnesium (Mg, ppm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eControl\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e220.3 (5.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e201.3 (7.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e201.0 (3.7)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWoodchips\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e218.5 (7.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e219.0 (10.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e211.3 (11.0)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCalcium (Ca, ppm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eControl\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e970.0 (46.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e741.3 (35.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e947.8 (46.7)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWoodchips\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1005.5 (54.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e796.3 (70.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1028.3 (62.2)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eSodium (Na, ppm)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eControl\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e21.0 (0.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e12.8 (2.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e21.3 (1.7)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWoodchips\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e19.5 (1.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e13.3 (2.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e22.8 (3.1)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCEC (Meq/100 g)\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eControl\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e12.3 (0.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e11.5 (0.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e13.3 (0.3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWoodchips\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e11.3 (0.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e10.8 (0.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e13.5 (0.3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"5\"\u003eValues in parentheses represent standard errors. CEC, Cation Exchange Capacity\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eWoodchip incorporation increased SOC and SON in the surface layer, consistent with expectations for high-C inputs (Grandy et al., \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2006\u003c/span\u003e; Poeplau \u0026amp; Don, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). Overall, our results indicate that incorporating willow woodchips at 40 Mg ha⁻\u0026sup1; can slow, but not eliminate, SOC and SON declines in potato-based systems. The observed differences were relatively small (~\u0026thinsp;0.06 kg C m⁻\u0026sup2; over five years) and appear to be transient, suggesting that single applications of coarse woody residues are unlikely to provide lasting protection against soil organic matter losses. Furthermore, the study was restricted to the 0\u0026ndash;15 cm soil layer and did not assess yield responses or deeper profile changes, which limits the scope of interpretation. Taken together, these findings suggest that while woodchip incorporation may offer incremental benefits, broader soil management strategies such as repeated applications, complementary organic amendments, or diversification of crop rotations will likely be required to achieve SOC improvements.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eWillow woodchip incorporation at 40 Mg ha⁻\u0026sup1; slowed, but did not prevent, SOC and SON losses in a potato-based cropping system at Fredericton, New Brunswick. The study was limited to the surface 0\u0026ndash;15 cm, without assessments of deeper soil layers or crop yield responses, and therefore results should be interpreted with these constraints in mind. The differences between treatments were modest (~\u0026thinsp;0.06 kg C m⁻\u0026sup2; over five years), indicating only a limited benefit for mitigating soil organic matter depletion. These findings suggest that coarse woody residues may modestly reduce the rate of SOC and SON decline in intensively managed systems, but the effect appears temporary and limited in magnitude. Additional management practices, including complementary organic amendments, crop diversification, or reduced tillage, will likely be required to achieve long-term SOC stabilization and nutrient retention.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eAcknowledgments\u003c/p\u003e\n\u003cp\u003eWe acknowledge that this research was conducted on the traditional and unceded territory of the Maliseet and Mi\u0026rsquo;kmaq Peoples. We appreciate the field and laboratory help from Medison White and Kayli McGarrigle. This work was supported by funding from Agriculture and Agri-Food Canada (grant J-001754.001.03 and grant J-002391.001.08).\u003c/p\u003e\n\u003cp\u003eDuring the preparation of this work the authors used ChatGPT (OpenAI) in order to assist with English grammar corrections, improvements in syntax, and occasional translations. After using this tool, the authors carefully reviewed and edited the content as needed and take full responsibility for the content of the publication.\u003c/p\u003e\n\u003cp\u003eThe authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Clinical trial number not applicable. Ethics, Consent to Participate, and Consent to Publish declarations not applicable. L.-P.C. designed and conducted the experiment, performed the analyses, and wrote the main manuscript text. K.M. and Y.K. carried out field sampling and laboratory analyses. S.L. and Y.J. served as project leaders, secured funding, coordinated the study, and provided critical revisions to the manuscript.\u003c/p\u003e\n\u003cp\u003eDeclarations of data Availability\u003c/p\u003e\n\u003cp\u003eThe datasets generated and analyzed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eChen, D., Barrett, R., Mimee, B. 2024. Prevalence of Verticillium spp. and Pratylenchus spp. in commercial potato fields in Atlantic Canada. American Journal of Potato Research 101, 291\u0026ndash;305. https://doi.org/10.1007/s12230-024-09957-3\u003c/li\u003e\n\u003cli\u003eComeau, L.-P., Goyer, C., Wagg, C., Unc, A. 2022. Ex situ soil respiration assessment using minimally disturbed microcosms and dried\u0026ndash;sieved soils; comparison of methods to assess soil health. Canadian Journal of Soil Science 102(2), 221\u0026ndash;234. https://doi.org/10.1139/cjss-2021-0143\u003c/li\u003e\n\u003cli\u003eDeLuca, T.H., Aplet, G.H. 2008. Charcoal and carbon storage in forest soils of the Rocky Mountain West. Frontiers in Ecology and the Environment 6(1), 18\u0026ndash;24. https://doi.org/10.1890/070070\u003c/li\u003e\n\u003cli\u003eDriscoll, B.A., Krzic, M., Comeau, L.-P., Eskelson, B.N.I., Li, S. 2023. Short-term response of soil aggregate stability and labile carbon to contour tillage, diversion terrace, grassed waterway, and tile drainage implementation. Canadian Journal of Soil Science 103(3), 394\u0026ndash;405. https://doi.org/10.1139/cjss-2022-0094\u003c/li\u003e\n\u003cli\u003eDriscoll, B.A., Krzic, M., Comeau, L.-P., Eskelson, B.N.I., Li, S. 2025. Response of CO₂, N₂O, and CH₄ fluxes to contour tillage, diversion terrace, grassed waterway, and tile drainage implementation. Frontiers in Soil Science 5, 1453324. https://doi.org/10.3389/fsoil.2025.1453324\u003c/li\u003e\n\u003cli\u003eGrandy, A.S., Robertson, G.P., Thelen, K.D. 2006. Do productivity and environmental trade-offs justify periodically cultivating no-till cropping systems? Agronomy Journal 98(6), 1377\u0026ndash;1383. https://doi.org/10.2134/agronj2006.0137\u003c/li\u003e\n\u003cli\u003eHangs, R.D., Ahmed, H.P., Schoenau, J.J. 2016. Influence of wood biochar amendments on soil nitrogen dynamics and greenhouse gas emissions in two contrasting soils. BioEnergy Research 9, 157\u0026ndash;171. https://doi.org/10.1007/s12155-015-9671-5\u003c/li\u003e\n\u003cli\u003eHendershot, W.H., Lalande, H., Duquette, M. 2007. Soil reaction and exchangeable acidity. In: Carter, M.R., Gregorich, E.G. (eds.) Soil Sampling and Methods of Analysis, 2nd edn. CRC Press, Boca Raton, FL, pp. 173\u0026ndash;178.\u003c/li\u003e\n\u003cli\u003eLal, R. 2004. Soil carbon sequestration impacts on global climate change and food security. Geoderma 123(1\u0026ndash;2), 1\u0026ndash;22. https://doi.org/10.1016/j.geoderma.2004.01.032\u003c/li\u003e\n\u003cli\u003eNyiraneza, J., Thompson, B., Geng, X., He, J., Jiang, Y., Fillmore, S., Stiles, K. 2017. Changes in soil organic matter over 18 yr in Prince Edward Island, Canada. Canadian Journal of Soil Science 97, 745\u0026ndash;756. https://doi.org/10.1139/cjss-2017-0033\u003c/li\u003e\n\u003cli\u003ePoeplau, C., Don, A. 2015. Carbon sequestration in agricultural soils via cultivation of cover crops \u0026ndash; a meta-analysis. Agriculture, Ecosystems \u0026amp; Environment 200, 33\u0026ndash;41. https://doi.org/10.1016/j.agee.2014.10.024\u003c/li\u003e\n\u003cli\u003eSix, J., Conant, R.T., Paul, E.A., Paustian, K. 2002. Stabilization mechanisms of soil organic matter: implications for C-saturation of soils. Plant and Soil 241(2), 155\u0026ndash;176. https://doi.org/10.1023/A:1016125726789\u003c/li\u003e\n\u003cli\u003eTisdall, J.M., Oades, J.M. 1982. Organic matter and water-stable aggregates in soils. Journal of Soil Science 33(2), 141\u0026ndash;163. https://doi.org/10.1111/j.1365-2389.1982.tb01755.x\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"discover-soil","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Discover Soil](https://link.springer.com/journal/44378)","snPcode":"44378","submissionUrl":"https://submission.nature.com/new-submission/44378/3","title":"Discover Soil","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Potato production, Soil organic carbon, Woodchip amendment, Soil organic nitrogen, Residue management, Atlantic Canada","lastPublishedDoi":"10.21203/rs.3.rs-7456686/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7456686/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eMaintaining soil organic carbon (SOC) in intensively managed potato systems is challenging due to frequent tillage and low residue return. A field experiment was conducted from 2019 to 2024 at the Agriculture and Agri-Food Canada Fredericton Research and Development Centre, New Brunswick, Canada, to evaluate the effects of willow (Salix spp.) woodchip incorporation on SOC, soil organic nitrogen (SON), and soil properties. Willow chips harvested from a local plantation were incorporated into the topsoil (0\u0026ndash;30 cm) at a rate of 40 Mg ha⁻\u0026sup1; in fall 2019. Surface soils (0\u0026ndash;15 cm) were sampled annually and analyzed for SOC, SON, pH, and nutrients. SOC and SON stocks declined over time in both treatments, but losses were consistently smaller under woodchip incorporation. By 2023, SOC in amended plots was approximately 0.06 kg C m⁻\u0026sup2; higher than in the control. SON declines were also slightly slower in the amended plots, while soil pH and most nutrient levels were unaffected. These findings suggest that woodchip incorporation may modestly reduce the rate of SOC and SON decline in potato-based systems, but the effect appears limited in magnitude and duration.\u003c/p\u003e","manuscriptTitle":"Willow woodchip incorporation moderates soil carbon and nitrogen losses in a potato production system in Atlantic Canada","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-22 00:36:08","doi":"10.21203/rs.3.rs-7456686/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-12-25T07:04:38+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-17T16:46:27+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"141027928166409205695540426596918844874","date":"2025-12-11T10:20:04+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"195727510436703665822737025877123307078","date":"2025-12-09T14:16:16+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-11-26T06:10:06+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"245685629315781928296683584622953304281","date":"2025-11-26T04:24:29+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-11-12T03:25:31+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-29T13:35:44+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-09-22T01:57:56+00:00","index":"","fulltext":""},{"type":"submitted","content":"Discover Soil","date":"2025-09-22T01:55:58+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"discover-soil","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Discover Soil](https://link.springer.com/journal/44378)","snPcode":"44378","submissionUrl":"https://submission.nature.com/new-submission/44378/3","title":"Discover Soil","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"8bea0637-4ba4-47d6-8775-e9ac698bf3d3","owner":[],"postedDate":"November 22nd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-03-23T10:26:16+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-22 00:36:08","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7456686","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7456686","identity":"rs-7456686","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}