Physico-Chemical Properties of Soil Under Acacia Senegal (L) Willd Plantation in Sahel Zone of Nigeria

Physico-Chemical Properties of Soil Under Acacia Senegal (L) Willd Plantation in Sahel Zone of Nigeria | 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 Research Physico-Chemical Properties of Soil Under Acacia Senegal (L) Willd Plantation in Sahel Zone of Nigeria Titus Ayodele Ampitan This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-135012/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background Acacia senegal (L) Wild known as gum Arabic tree, is a nitrogen fixing tree and a drought resistant species with potentials to improve infertile soils is planted in Sahel zone of Jigawa State, Nigeria for the production of gum arabic. However, there is dearth of information on the soil physico-chemical properties under plantation. Methods Soil samples were collected from four 30 x 30m plots in the plantation and another plot in open woodland (control). In each plot, three replicate soil samples were taken from 0-15cm, 15-30cm and 30-60cm soil depths analyzed for micro and macronutrients, while soil acidity was determined both in water and 0.01M CaCl 2 . Results The general soil texture of the plantation is loamy sand but with slight textural differentiation under the open woodland. Results indicated that physico-chemical properties of soils under the plantation were significantly different at P < 0.05 compared with the control. The mean soil bulk density ranged from 1.6g/cm 3 in the plantation to 1.8g/cm 3 in the open woodland. The high values of soil bulk density might be ascribed to loss of organic matter as a result of soil erosion and animal grazing which are common occurrences. Conclusion From the result of the study soil physico-chemical properties under the plantation are high and have more beneficial effects on the trees unlike the open woodland. Forestry Chemical Biology Plant Physiology and Morphology Acacia senegal plantation soil nutrients trees Background Trees perform a dynamic role of maintaining soil organic matter levels through the supply of litter and root residues, which in turn improve the fertility of the soil. Trees take up different amounts and different proportion of nutrients from a soil according to their species. However, the amounts taken depend on the soil conditions (Russell, 1973). Several studies have reported positive influence of trees on soil fertility and conservation (Kessler, 1992 and Bill, 2007 ). Acacia senegal for example, has special capacity to enrich poor soils, rehabilitate degraded land during fallow periods (Spore, 2001) using its root to break up hard clay soils, thus increasing aeration and drainage as a result, making essential nutrients more easily available and to mitigate desertification as well. Its use for associated food crops and its value for the production of gum arabic and good fuel wood even in areas with an extended dry season make it a very worthwhile species for large-scale exploitation as an agroforestry and a fuel wood species (NAS, 1979). However, there is inadequate information on the soil physico-chemical properties of Acacia senegal (L) Wild trees in plantation in the Sahel zone of Nigeria where it is found in the wilds and plantations and that makes this study necessary. Materials And Methods Soil fertility study was carried out in Maifari Gum Arabic plantations in Maigatari Local Government Area of Jigawa State, Nigeria. The plantation covered an area of 20 hectares with an espacement of 6 × 6 m between and within the rows. The plantation lies between latitudes 12 0 48 and 18 0 20 N and longitudes 9 0 27 and 52 0 16 E with an elevation of about 350 m above sea level. Experimental design and layout The study investigated the effects of Acacia senegal on soil by comparing the soil properties of Acacia senegal plantation with that of a natural open woodland. The plantation was divided into plots of 30 m x 30 m with four plots randomly chosen with the adjacent natural open woodland of the same size selected as a control. In each plot, twenty five quadrats of 6 m x 6 m were established and three quadrats were randomly chosen. The soil samples were collected from the depths of 0–15 cm, 15–30 cm and 30–60 cm. The study was conducted using a randomized complete block design. Soil Analysis The soil samples were collected in polythene bags and air-dried in the laboratory for several days. Samples were gently crushed with porcelain pestle and mortar and sieved through a 2 mm sieve to remove coarse fragments. The fine soils separated were stored in polythene bags and taken to the Department of Soil Science, Ahmadu Bello University, Zaria, Nigeria for laboratory analyses. Particle size distribution and bulk density were determined using the hydrometer method, while cores were oven-dried to constant weight at 105 0 C for two days and expressed as mass of dry soil per unit volume of moist soil. The soil pH was determined both in water and 0.01M CaCl 2 solution using a soil solution ratio of 1:2.5 (IITA, 1979; AWWA, 1992). Cation exchange capacity (CEC) of the soil was determined with 1M NH 4 OAC (1M ammonium acetate) buffered at pH 7.0 (Chapman, 1965, Rowell, 1994). Exchangeable Cation exchange capacity (ECEC) was calculated from the summation of exchangeable bases determined by 1M NH 4 0Ac extraction and the exchange acidity by 1M KCl extraction (Anderson and Ingram, 1998 ). Organic carbon was determined by chromic acid digestion method of Walkley and Black (1934). Total N was determined using the micro-Kjeldahl digestion technique (Bremmer, 1982), while available P was estimated colorimetrically by the molybdo-phosphoric- blue method using ascorbic acid as a reducing agent (Bray and Kurtz, 1945 ). Field and laboratory data generated were subjected to analysis of variance (ANOVA). Differences in mean values were tested at 0.05 level of significance with Duncan’s multiple range tests (DMRTs). Results And Discussion The general soil texture of the plantation is loamy sand. However, under the open woodland used as the control (natural open woodland), the soil had a slight textural differentiation (Table 1). The texture of the soil is sandy, especially at the top soil (0 -15 cm depth). This is so as the study area is a part of Sahel savanna of Nigeria which is characterized by sandy to sandy loam soils (Odunze and Ogunwole, 2000). Table 1: Mean soil physical properties at different depths under Acacia senegalensis plantation and natural woodland Plot Depth (cm) Sand (g/kg) Silt (g/kg) Clay (kg) Textural Class 1 0-15 853 100 47 Loamy sand 15-30 860 80 60 Loamy sand 30-60 840 73 87 Loamy sand 2 0-15 847 107 47 Loamy sand 15-30 873 73 53 Loamy sand 30-60 847 87 67 Loamy sand 3 0-15 833 147 20 Loamy sand 15-30 847 100 53 Loamy sand 30-60 853 93 53 Loamy sand 4. 0-15 867 100 33 Loamy sand 15-30 827 107 67 Loamy sand 30-60 840 67 93 Loamy sand Natural woodland (Control) 0-15 887 87 27 Sand 15-30 867 87 47 Loamy sand 30-60 873 73 53 Loamy sand Table 2: Mean, standard deviation and standard error of mean of soil bulk density under Acacia senegalenis plantation and natural woodland Treatment Mean (g/cm 3 ) Plot 1 1.6 Plot 2 1.60.035 Plot 3 1.7 Plot 4 1.6 Woodland (Control) 1.8 Table 3: ANOVA result for the Mean Soil Bulk Density Parameter Df MS F P-level Plot 4 .021 8.532 0.003* Error 10 .002 * = Significant The amount of silt and clay in the plantation was small compared to the value obtained for the sand. The silt contents were higher at 0 - 15 cm depths both in the plantation and under the natural open woodland. However, the content of silt was much higher in the plantation than in the natural open woodland. This could be attributed to the vegetation cover of the Acacia senegal which helps to prevent soil erosion within the plantation. The clay content was also high at 0 - 15 cm soil depth both in the plantation and the natural open woodland but not as high as that of silt and it increased along the soil depth. This may be as a result of inadequate plant materials (litter). In a similar study under Prosopis cineraria plantation in semi-arid areas in India, Shankarnarayan et al ., (1986) observed that silt and clay content of soil increased up to a depth of 120 cm as compared to the surrounding open fields which are devoid of trees. These changes in soil physical properties resulted in the maintenance of soil moisture beneath the trees. The mean soil bulk density ranged from 1.6 g/cm 3 in plot 1 to 1.8 g/cm 3 in the natural open woodland (Table 2). However, the results of analysis of variance indicated a positively high significant value at P < 0.05 (Table 3). The high mean values of soil bulk density obtained in both the plantation and the natural open woodland might be ascribed to the loss of organic matter through constant exposure of the plantation to sandstorms that usually blow away the rich fine particles of the top soil and the compaction of the soil by the roaming animals that were usually found grazing in the plantation. The case of the natural open woodland is a good example of a plot devoid of vegetation that could hardly prevent the sandstorms from blowing away the fine soil particles that are rich in organic matter. Soil chemical properties The general distribution of soil pH trend was a decrease from the top (0 - 15 cm) to the lower soil depth (30 – 60 cm). The results of analysis of variance tests for pH (H 2 0) indicated significant differences at different soil depths, while across the plots, there was no significant difference at p = 0.05. Also, for the pH (CaCl 2 ), there were significant differences among soil depths but not across plots (Tables 4 and 5). A similar trend was observed along soil depth by Lechisa et al. (2014) under different land use systems in Gindeberet district, Ethiopia. The reason attributed was the reduction of Ca and Mg ions along soil depth which lower soil pH from top to down the soil layers (Soto and Diazfierroz, 1993). The amount of organic carbon was significantly higher in the topsoil and decreased with soil depth and following the same trend for total nitrogen (Table 4). This is in line with some studies (Jackson et al., 1996; Carter et al., 1997; Mohamed, 2005). Since A. senegal is a deciduous tree that sheds its leaves during the dry season and is adapted to harsh environmental conditions, the accumulation of organic carbon in the topsoil may be as a result of leaf litter decomposition. According to Schlesinger et al. (1996) and Burke et al. (1998), soil organic carbon storage and distribution are controlled by the balance of carbon inputs from plant production and outputs through decomposition. The carbon-nitrogen ratio (C/N) in the plantation and natural open woodland decreased with increasing soil depth following the pattern of organic matter distribution (Table 4). The analysis of variance showed that differences in the C/N ratio were statistically significant across the soil depths. But the low C/N values of the 0 – 15 cm soil depth may be ascribed to higher fresh litter accumulation, which lowers the rates of mineralization. The mean value of available phosphorous was statistically significant both for the soil depth and across the plots. It should be noted that available P under the natural woodland was low and also decreased with soil depth. The decrease with depth is ascribed to decrease in organic matter levels as noted by Samndi (2005) under Tectona grandis plantation in Nimbia forest, Kaduna State, Nigeria. This phenomenon was observed by Ogunyebi (2008) in the study of decomposition of Gmelina arborea leaf litter in the lowland rainforest of Nigeria. Table 4: Soil physical and chemical properties as influenced by soil depth under Acacia senegal plantation in Jigawa State Soil Depth Clay Silt Sand pH H 2 O pH (CaCl 2 ) OC TN C:N AP Ca Mg K Na ECEC CEC 0-15cm 3.467a 10.800b 85.733a 5.947c 5.553c 0.352b 0.086a 11.227b 5.251b 3.787b 0.280a 0.177b 0.114a 4.626b 5.967a 15-30cm 5.600b 8.933a 85.467a 5.160b 4.553b 0.127a 0.035a 4.915a 3.327a 2.886a 0.473b 0.107a 0.116a 4.020ab 5.567a 30-60cm 7.067c 7.867a 85.067a 4.713a 4.233a 0.075a 0.025a 3.465a 3.209a 2.377a 0.716c 0.089a 0.145b 3.928a 5.773a Mean values with the same letters are not significantly different at 5% probability level by DMRT Table 5: Soil physical and chemical properties as influenced by plot under Acacia senegal plantation in Jigawa State Plot Clay Silt Sand pH H 2 O pH (CaCl 2 ) OC TN C:N AP Ca Mg K Na ECEC CEC 1 6.444b 8.444a 85.111a 5.567c 4.822b 0.207ab 0.127b 3.341a 2.139a 2.231a 0.292a 0.088a 0.106a 3.183a 4.344a 2 5.556ab 8.889a 85.556a 5.189b 4.800b 0.1889ab 0.029a 7.977ab 3.891b 2.680a 0.540b 0.138b 0.102a 3.793a 5.478b 3 4.222a 11.333b 84.444a 5.500bc 5.111b 0.253b 0.027a 9.772b 3.988b 3.874b 0.660c 0.139b 0.111a 5.117b 6.167bc 4 6.444b 9.111a 84.444a 5.378bc 4.844b 0.162ab 0.035a 5.236ab 4.473bc 3.809b 0.611bc 0.134b 0.148b 5.058b 6.822c Control 4.222a 8.222a 85.556b 4.733a 4.322a 0.111a 0.026a 6.354ab 5.154c 2.489a 0.346a 0.123b 0.159b 3.806a 6.033bc Mean values with the same letters are not significantly different at 5% probability level by DMRT The exchangeable cations The Exchangeable cations investigated in the soil of the plantation and the natural open woodland are calcium (Ca), magnesium (Mg), potassium (K) and sodium (Na). While the calcium and potassium decreased as the soil depth increased, both magnesium and sodium increased as the soil depth increased. The results of decreasing calcium and potassium with soil depth were in agreement with the findings of Oyun (1991) and could be a result of large uptake and storage of Ca and K by the trees. The increase of Mg and Na down the soil depths is in consonance with Tedela (2004) and might be attributed to less utilization of these nutrients by Acacia senegal . However, the increase of Na along the soil depth could cause soil salinity which is a common phenomenon in dry areas, such as the study area (Oyun, 1991). The ECEC decreased as the soil depth increased and is low in values. According to Nwachokor et al (2009), a low ECEC less than 4 cmol/kg implies a low capacity for the soil holding cations against leaching. The CEC of soils commonly range from 3 to 50cmol/kg, comparatively therefore, the soil of the study area had low CEC. The low CEC values could probably be as a result of low organic matter in the soil. This could be attributed to the fact that the soil of arid zones is characterized by low organic matter and clay, oxides and hydroxides of iron and aluminium; all these could lead to poor growth of Acacia senegalensis in the plantation. Conclusion A comparison of soil nutrient contents of the study area showed that the Acacia senegal plantation nutrient contents were higher than what were obtained in the natural open woodland. The higher nutrient contents obtained under the plantation plots may be as a result of mineralization resulting from higher number of Acacia senegal trees which shed their leaves making the leaves available for decomposition thereby increasing the soil organic matter, nitrogen content, increase availability of micro-nutrient (Zn, Mn and Cu) in the soil surface and improved the soil structure. It can therefore be concluded that the decline in soil fertility in the natural open woodland is often as a result of less mineralization of litter which leads to the depletion of the nutrient pool of organic matter. The study has also shown the influence of trees in soil physical properties which are very important in augmenting the overall capacity of the land to produce. The removal of the vegetative cover from the soil results in increases in bulk density, decreases in porosity and reduction in infiltration rate. This ultimately will reduce land productivity if not properly taken care of. In line with this, researches have demonstrated influence of trees in reversing this problem. This effect was associated with the influence of tree roots and biomass return in terms of mulching or tree litter on the structure and texture of the soils. Recommendation Judging from the above, the soil quality and productivity of the natural open woodland can be restored by planting the area up with Acacia senegal trees or any other tree(s) as trees will promote high biological activities of soil fauna, improve soil organic matter content and replacing the nutrients lost to soil or wind erosion and animal grazing on the land. Declarations Ethics approval and consent to participate: Not applicable Consent for publication: Not applicable Availability of data and materials : All data generated or analysed during the study are included in this manuscript. Competing interests : We (ATA and ADI) declare that we have no competing interests Funding : The funding of the project, writing and publication were done by the authors Authors’ contribution : A TA planned and carried out the research while ADI analysed the data collected and the writing of the publication was jointly done by both authors (ATA and ADI). Acceptance and Confirmation : All authors of the publication have read and agreed to its content and we are accountable for all aspects of the accuracy and integrity of the publication in accordance with ICMJE criteria. We (ATA and ADI) state that the article is original and has not already been published in a journal and is not currently under consideration by another journal. That we agree to terms of the SpringerOpen Copyright and License Agreement. Authors’ Information : ATA is a researcher with Forestry Research Institute of Nigeria and hold PhD degree from University of Ibadan, Nigeria in Forest Ecology and Silviculture with specialization in forest soil, plant nutrition and agroforestry. He is a member of many societies both locally and internationally including the following Forestry Association of Nigeria (FAN), Society for Conservation Biology (SCB) and International Society for Tropical Foresters (ISTF). ADI is a Senior Lecturer in Forest Biometrics with Ecole de Foresterie Tropicale, Universite Nationale dÁgriculture, Porto-Novo, Benin Republic. Research interests include forest inventory, modelling individual tree characteristics, tree heights, model of aboveground biomass, modelling crowns and roots, quantitative characteristics of forest stands, stand density, site quality, growth yield models, statistically designed experiments in forestry and greenhouse experiments. References American Water Works Association (AWWA) (1992). Standard method for the examination of water and waste water. In: A. E. Greenbag, C. S. Lenore and A. D. Eatten (eds.) Washington, D. C. Anderson, J. M and S. J. Ingram 1998. Tropical soil biology and Fertility . A handbook of methods. Information Press U. K. 221 Pp. Belsky, A. J.; R. G. Amudson; J. M. Duxbury; S. J. Riha; A. R. Ali and S. M. Mwonga 1989. The effects of trees on their physical, chemical and biological environments in a semi-arid savanna in Kenya. J. of Applied Ecol. 26: 1005-1024. Bill, M. 2007. Trees and their energy transactions. The Overstory, No. 92.Agroforestry Net Inc., Holualoa, Hawaii, USA. 10 Pp. Bray, R. H. and L. T. Kurtz 1945. Determination of total organic and available forms of phosphorous in soils. Soil Science 59: 39-45. Bremner, J. M., 1982. Inorganic nitrogen In: Page, A. L.; Miller, R. H. and Keeney, D. R. (ed). Methods of soils analysis, Part 2. Amer. Soc. of Agron. Madison. 595-624 Burke, I. C., W. K. Lauenroth; M. A.Vinto; P. B. Hook; R. H. Kelly; H. E. Epstein; M. R. Aguiar; M. D. Robles; M. O. Aguilera and R. A. Gill 1998. Plant-Soil interaction in temperate grasslands. Biogeochemistry 42: 121- 143. Carter, M. R.; D. A. Angers; E. G. Gregorich and M. A. Bolinder 1997. Organic carbon and nitrogen stocks and storage profile in cool, humid soils of eastern Canada, Canadian J. of Soil Sc. 77: 205-210. Chapman, H. D. 1965. Cation exchange capacity. In C. A. Black (ed).Methods of soil analysis. Part 2, Agron. No 9, ASA Madison Wisconsin, USA. 891- 901. IITA, 1979. Selected methods for soil and plant analysis. International Institute of Tropical Agriculture, Ibadan. Manual, serie s No 1: 35 Pp. Jackson, R. B.; J. Canadell; J. R. Ehleringer; H. A. Mooney; O. E. Sala and E. D. Schulze 1996. A global analysis of root distributions for terrestrial biome. Oecologia 108: 389 – 411. Kessler, J. J. 1992. The influence of Karite (V itellaria paradoxa ) and nere ( Parkia biglobosa) trees on sorghum production in Burkina Faso. Agroforestry Systems 17: 97-118. Lechisa, T.; C. Achalu and A. Alemayehu 2014. Dynamics of soil fertility as influenced by different land use systems and soil depth in west Show zone , Gindeberet, District, Ethiopia. Journal of Agriculture, Forestry and Fisheries 3(6): 489-494. Mohamed, A. G. 2005. Improvement of traditional Acacia senegal agroforestry: Ecophysiological characteristics as indicators for tree-crop interaction on sandy soil in western Sudan. A Paper presented for discussion at the University of Helsinki on 4 March, 2005, 98 Pp. NAS, 1979. Acacia auriculiformis . Report of an Ad Hoc Panel of the Advisory Committee on Technology Innovation, NAS Washington, D. C. 165-171. Nwachokor, M. A.; F. O. Uzu and W. A. Molindo 2009. Variations in physicochemical properties and productivity implications for four soils in the derived savanna of Southern Nigeria. American-Eurasian J. of Agronomy 2 (3): 124-129. Odunze, A. C. and J. O. Ogunwole 2002 . Proven on-farm soil conservation technology for sustainable fertility management in northern Nigeria . Fed. Min of Agric and Rural Development and FAO. 1-2 Pp Ogunyebi, L. A. 2008. Nutrient dynamics associated with litterfall and mineralization o f Gmelina arborea Roxb. in a lowland rain forest . A PhD Thesis submitted to Dept. of Forest Resources Management, Faculty of Agric. and Forestry, University of Ibadan, Nigeria, 189 Pp. Oyun, M. B. 1991 . Effect of soil salinity on three selected savanna tree species in Bauchi State, Nigeria . A M.Sc. Thesis submitted to Dept. of Forest Resources Management, University of Ibadan, Nigeria. Rowell, D. L. 1994. Soil science: Methods and applications. Addison Wesley Longman Singapore Publishers Ltd., England U. K. 350 Pp. Russell, E. W., 1973. Soil conditions and plant growth. Longman Group Ltd., N. Y. 284-326 Pp. Samndi, A. M., 2005. Characterization and classification of soils under long- term Teak (Tectona grandis) plantation in Southern Guinea savanna of Nigeria. A PhD Thesis submitted to Dept. of Soil Science, A. B. U. Zaria, Nigeria. 280 Pp. Unpublished. Schlesinger, W.; J. A. Raikes; A. E. Hartley and A. F. Cross 1996 . On the spatial pattern of soil nutrients in desert ecosystems. Ecology 77: 364-374. Shankaranaraya, K. A. and L. W. Harsh 1986. Agroforestry in the arid zones of India. Contibution No. 22 of the series of agroforestry system descriptions under, ICRAF’s agroforestry system project (USAID) 1- 22 Pp. Soto, B. and F. Diazfierroz 1993. Interaction between plant ash leachates and soil. International Journal of Wildlife , 3:207-216. Spore, 2001. New network, by gum. Spore No 91 , CTA, Wageningan, Netherlands. 16. Tedela, T. H. 2004. Root biomass and nutrient distribution study in an Eucalyptus camaldulensis plantation in Ethiopia. A M.Sc. thesis submitted to University of Natural Resources and Applied Life Science, Vienna. 106Pp. Unpublished. Walkley, A. and I. A. Black 1934. An examination of the Degtjiareff method for determining soil organic matter and a proposed modification of chromic and titration method. Soil Sci. 37: 29-38 Cite Share Download PDF Status: Posted Version 1 posted 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-135012","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research","associatedPublications":[],"authors":[{"id":7019393,"identity":"62993bc2-92af-474e-aa8f-186489558d2f","order_by":0,"name":"Titus Ayodele Ampitan","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAwUlEQVRIiWNgGAWjYFACHiA+wCAHYZCixZh0LYkNRGvh71978MGHMzbpG46fBTIY7OR0GwhokbjxLtlwxo203A1n8oAMhmRjswOErLlxxkya58Ph3A0HcoAMhgOJ2whpkb9xxvw3UEu6wfk3RGoxON9jxsxz43CCwQ1ibTG8wZcsOeNMmuHMG2+MDWcYEOEXufNnD374cMxGnu98juGDDxV2coS9L5EAoRXAKg0IKQcBfqih8g3EqB4Fo2AUjIIRCQCnTEmCIBJhQQAAAABJRU5ErkJggg==","orcid":"","institution":"Forestry Research Institute of Nigeria","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Titus","middleName":"Ayodele","lastName":"Ampitan","suffix":""}],"badges":[],"createdAt":"2020-12-23 16:25:54","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-135012/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-135012/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":13640673,"identity":"1cbcffea-9dec-4d33-8ac6-ff56806c5f4a","added_by":"auto","created_at":"2021-09-17 09:00:51","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":393487,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-135012/v1/3d1c7fcd-b355-45c8-9294-152c2c0c0bc3.pdf"}],"financialInterests":"","formattedTitle":"\u003cp\u003ePhysico-Chemical Properties of Soil Under Acacia Senegal (L) Willd Plantation in Sahel Zone of Nigeria\u003c/p\u003e","fulltext":[{"header":"Background","content":" \u003cp\u003eTrees perform a dynamic role of maintaining soil organic matter levels through the supply of litter and root residues, which in turn improve the fertility of the soil. Trees take up different amounts and different proportion of nutrients from a soil according to their species. However, the amounts taken depend on the soil conditions (Russell, 1973). Several studies have reported positive influence of trees on soil fertility and conservation (Kessler, 1992 and Bill, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2007\u003c/span\u003e). \u003cem\u003eAcacia senegal\u003c/em\u003e for example, has special capacity to enrich poor soils, rehabilitate degraded land during fallow periods (Spore, 2001) using its root to break up hard clay soils, thus increasing aeration and drainage as a result, making essential nutrients more easily available and to mitigate desertification as well. Its use for associated food crops and its value for the production of gum arabic and good fuel wood even in areas with an extended dry season make it a very worthwhile species for large-scale exploitation as an agroforestry and a fuel wood species (NAS, 1979).\u003c/p\u003e \u003cp\u003eHowever, there is inadequate information on the soil physico-chemical properties of \u003cem\u003eAcacia senegal\u003c/em\u003e (L) Wild trees in plantation in the Sahel zone of Nigeria where it is found in the wilds and plantations and that makes this study necessary.\u003c/p\u003e "},{"header":"Materials And Methods","content":" \u003cp\u003eSoil fertility study was carried out in Maifari Gum Arabic plantations in Maigatari Local Government Area of Jigawa State, Nigeria. The plantation covered an area of 20 hectares with an espacement of 6\u0026thinsp;\u0026times;\u0026thinsp;6\u0026nbsp;m between and within the rows. The plantation lies between latitudes 12\u003csup\u003e0\u003c/sup\u003e 48 and 18\u003csup\u003e0\u003c/sup\u003e 20\u0026nbsp;N and longitudes 9\u003csup\u003e0\u003c/sup\u003e 27 and 52\u003csup\u003e0\u003c/sup\u003e 16 E with an elevation of about 350\u0026nbsp;m above sea level.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eExperimental design and layout\u003c/h2\u003e \u003cp\u003eThe study investigated the effects of \u003cem\u003eAcacia senegal\u003c/em\u003e on soil by comparing the soil properties of \u003cem\u003eAcacia senegal\u003c/em\u003e plantation with that of a natural open woodland. The plantation was divided into plots of 30\u0026nbsp;m x 30\u0026nbsp;m with four plots randomly chosen with the adjacent natural open woodland of the same size selected as a control. In each plot, twenty five quadrats of 6\u0026nbsp;m x 6\u0026nbsp;m were established and three quadrats were randomly chosen. The soil samples were collected from the depths of 0\u0026ndash;15\u0026nbsp;cm, 15\u0026ndash;30\u0026nbsp;cm and 30\u0026ndash;60\u0026nbsp;cm. The study was conducted using a randomized complete block design.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eSoil Analysis\u003c/h2\u003e \u003cp\u003eThe soil samples were collected in polythene bags and air-dried in the laboratory for several days. Samples were gently crushed with porcelain pestle and mortar and sieved through a 2\u0026nbsp;mm sieve to remove coarse fragments. The fine soils separated were stored in polythene bags and taken to the Department of Soil Science, Ahmadu Bello University, Zaria, Nigeria for laboratory analyses. Particle size distribution and bulk density were determined using the hydrometer method, while cores were oven-dried to constant weight at 105\u003csup\u003e0\u003c/sup\u003eC for two days and expressed as mass of dry soil per unit volume of moist soil. The soil pH was determined both in water and 0.01M CaCl\u003csub\u003e2\u003c/sub\u003e solution using a soil solution ratio of 1:2.5 (IITA, 1979; AWWA, 1992). Cation exchange capacity (CEC) of the soil was determined with 1M NH\u003csub\u003e4\u003c/sub\u003eOAC (1M ammonium acetate) buffered at pH 7.0 (Chapman, 1965, Rowell, 1994). Exchangeable Cation exchange capacity (ECEC) was calculated from the summation of exchangeable bases determined by 1M NH\u003csub\u003e4\u003c/sub\u003e0Ac extraction and the exchange acidity by 1M KCl extraction (Anderson and Ingram, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e1998\u003c/span\u003e). Organic carbon was determined by chromic acid digestion method of Walkley and Black (1934). Total N was determined using the micro-Kjeldahl digestion technique (Bremmer, 1982), while available P was estimated colorimetrically by the molybdo-phosphoric- blue method using ascorbic acid as a reducing agent (Bray and Kurtz, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e1945\u003c/span\u003e). Field and laboratory data generated were subjected to analysis of variance (ANOVA). Differences in mean values were tested at 0.05 level of significance with Duncan\u0026rsquo;s multiple range tests (DMRTs).\u003c/p\u003e \u003c/div\u003e "},{"header":"Results And Discussion","content":"\u003cp\u003eThe general soil texture of the plantation is loamy sand. However, under the open woodland used as the control (natural open woodland), the soil had a slight textural differentiation (Table 1). The texture of the soil is sandy, especially at the top soil (0 -15 cm depth). This is so as the study area is a part of Sahel savanna of Nigeria which is characterized by sandy to sandy loam soils (Odunze and Ogunwole, 2000).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1: Mean soil physical properties at different depths under \u003cem\u003eAcacia senegalensis \u003c/em\u003eplantation and natural woodland\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" width=\"0\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e\u003cstrong\u003ePlot\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e\u003cstrong\u003eDepth (cm)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e\u003cstrong\u003eSand (g/kg)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e\u003cstrong\u003eSilt (g/kg)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u003cstrong\u003eClay (kg)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003e\u003cstrong\u003eTextural Class\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e1\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e0-15\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e853\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e100\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 47\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eLoamy sand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e15-30\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e860\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e\u0026nbsp; 80\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eLoamy sand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e30-60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e840\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e\u0026nbsp; 73\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 87\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eLoamy sand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e2\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e0-15\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e847\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e107\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 47\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eLoamy sand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e15-30\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e873\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp; 73\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 53\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eLoamy sand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e30-60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e847\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp; 87\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 67\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eLoamy sand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e0-15\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e833\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e\u0026nbsp;147\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 20\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eLoamy sand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e15-30\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e847\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e\u0026nbsp;100\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp; \u0026nbsp;\u0026nbsp;\u0026nbsp;53\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eLoamy sand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e30-60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e853\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp; 93\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 53\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eLoamy sand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e4.\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e0-15\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e867\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e\u0026nbsp;100\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 33\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eLoamy sand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e15-30\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e827\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e\u0026nbsp;107\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 67\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eLoamy sand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e30-60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e840\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp; 67\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 93\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eLoamy sand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003eNatural woodland\u003c/p\u003e\n\u003cp\u003e(Control)\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e0-15\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e887\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp; 87\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 27\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eSand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e15-30\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e867\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp; 87\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 47\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eLoamy sand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"106\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e30-60\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"92\"\u003e\n\u003cp\u003e873\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"87\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp; 73\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 53\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"116\"\u003e\n\u003cp\u003eLoamy sand\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2: Mean, standard deviation and standard error of mean of soil bulk density under \u003cem\u003eAcacia senegalenis\u003c/em\u003e plantation and natural woodland\u0026nbsp; \u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd width=\"134\"\u003e\n\u003cp\u003e\u003cstrong\u003eTreatment\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"236\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; \u0026nbsp;\u0026nbsp;\u0026nbsp;Mean (g/cm\u003csup\u003e3\u003c/sup\u003e)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"134\"\u003e\n\u003cp\u003ePlot 1\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"236\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 1.6\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"134\"\u003e\n\u003cp\u003ePlot 2\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"236\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 1.60.035\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"134\"\u003e\n\u003cp\u003ePlot 3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"236\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 1.7\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"134\"\u003e\n\u003cp\u003e\u0026nbsp;Plot 4\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"236\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 1.6\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"134\"\u003e\n\u003cp\u003eWoodland (Control)\u0026nbsp;\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"236\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; 1.8\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3: ANOVA result for the Mean Soil Bulk Density\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd width=\"96\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; Parameter\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; Df\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"108\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; MS\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"114\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; F\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"95\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; \u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eP-level\u0026nbsp;\u0026nbsp; \u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"96\"\u003e\n\u003cp\u003ePlot\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e4\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"108\"\u003e\n\u003cp\u003e.021\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"114\"\u003e\n\u003cp\u003e8.532\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"95\"\u003e\n\u003cp\u003e0.003*\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"96\"\u003e\n\u003cp\u003eError\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e10\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"108\"\u003e\n\u003cp\u003e.002\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"114\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"95\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"96\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"84\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"108\"\u003e\n\u003cp\u003e\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"114\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"95\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e* = Significant\u003c/p\u003e\n\u003cp\u003eThe amount of silt and clay in the plantation was small compared to the value obtained for the sand. The silt contents were higher at 0 - 15 cm depths both in the plantation and under the natural open woodland. However, the content of silt was much higher in the plantation than in the natural open woodland. This could be attributed to the vegetation cover of the \u003cem\u003eAcacia senegal \u003c/em\u003ewhich helps to prevent soil erosion within the plantation. The clay content was also high at 0 - 15 cm soil depth both in the plantation and the natural open woodland but not as high as that of silt and it increased along the soil depth. This may be as a result of inadequate plant materials (litter).\u0026nbsp; In a similar study under \u003cem\u003eProsopis cineraria\u003c/em\u003e plantation in semi-arid areas in India, Shankarnarayan \u003cem\u003eet al\u003c/em\u003e., (1986) observed that silt and clay content of soil increased up to a depth of 120 cm as compared to the surrounding open fields which are devoid of trees. These changes in soil physical properties resulted in the maintenance of soil moisture beneath the trees.\u003c/p\u003e\n\u003cp\u003eThe mean soil bulk density ranged from 1.6 g/cm\u003csup\u003e3\u003c/sup\u003e in plot 1 to 1.8 g/cm\u003csup\u003e3\u003c/sup\u003e in the natural open woodland (Table 2). However, the results of analysis of variance indicated a positively high significant value at P \u0026lt; 0.05 (Table 3). The high mean values of soil bulk density obtained in both the plantation and the natural open woodland might be ascribed to the loss of organic matter through constant exposure of the plantation to sandstorms that usually blow away the rich fine particles of the top soil and the compaction of the soil by the roaming animals that were usually found grazing in the plantation. The case of the natural open woodland is a good example of a plot devoid of vegetation that could hardly prevent the sandstorms from blowing away the fine soil particles that are rich in organic matter.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eSoil chemical properties\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; \u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe general distribution of soil pH trend was a decrease from the top (0 - 15 cm) to the lower soil depth (30 \u0026ndash; 60 cm). The results of analysis of variance tests for pH (H\u003csub\u003e2\u003c/sub\u003e0) indicated significant differences at different soil depths, while across the plots, there was no significant difference at p = 0.05. Also, for the pH (CaCl\u003csub\u003e2\u003c/sub\u003e), there were significant differences among soil depths but not across plots (Tables 4 and 5). A similar trend was observed along soil depth by Lechisa \u003cem\u003eet al.\u003c/em\u003e (2014) under different land use systems in Gindeberet district, Ethiopia. The reason attributed was the reduction of Ca and Mg ions along soil depth which lower soil pH from top to down the soil layers (Soto and Diazfierroz, 1993).\u003c/p\u003e\n\u003cp\u003eThe amount of organic carbon was significantly higher in the topsoil and decreased with soil depth and following the same trend for total nitrogen (Table 4). This is in line with some studies (Jackson \u003cem\u003eet al.,\u003c/em\u003e 1996; Carter \u003cem\u003eet al.,\u003c/em\u003e 1997; Mohamed, 2005). Since \u003cem\u003eA. senegal\u003c/em\u003e is a deciduous tree that sheds its leaves during the dry season and is adapted to harsh environmental conditions, the accumulation of organic carbon in the topsoil may be as a result of leaf litter decomposition. According to Schlesinger \u003cem\u003eet al.\u003c/em\u003e (1996) and Burke \u003cem\u003eet al. \u003c/em\u003e(1998), soil organic carbon storage and distribution are controlled by the balance of carbon inputs from plant production and outputs through decomposition.\u003c/p\u003e\n\u003cp\u003eThe carbon-nitrogen ratio (C/N) in the plantation and natural open woodland decreased with increasing soil depth following the pattern of organic matter distribution (Table 4). The analysis of variance showed that differences in the C/N ratio were statistically significant across the soil depths. But the low C/N values of the 0 \u0026ndash; 15 cm soil depth may be ascribed to higher fresh litter accumulation, which lowers the rates of mineralization.\u003c/p\u003e\n\u003cp\u003eThe mean value of available phosphorous was statistically significant both for the soil depth and across the plots. It should be noted that available P under the natural woodland was low and also decreased with soil depth. The decrease with depth is ascribed to decrease in organic matter levels as noted by Samndi (2005) under \u003cem\u003eTectona grandis\u003c/em\u003e plantation in Nimbia forest, Kaduna State, Nigeria. This phenomenon was observed by Ogunyebi (2008) in the study of decomposition of \u003cem\u003eGmelina arborea\u003c/em\u003e leaf litter in the lowland rainforest of Nigeria. \u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4: Soil physical and chemical properties as influenced by soil depth under \u003cem\u003eAcacia senegal \u003c/em\u003e\u0026nbsp;plantation in Jigawa State\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" width=\"0\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd colspan=\"2\" width=\"50\"\u003e\n\u003cp\u003e\u003cstrong\u003eSoil \u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDepth\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd colspan=\"2\" width=\"46\"\u003e\n\u003cp\u003e\u003cstrong\u003eClay\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd colspan=\"2\" width=\"59\"\u003e\n\u003cp\u003e\u003cstrong\u003eSilt\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u003cstrong\u003eSand\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"15\"\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u003cstrong\u003epH\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eH\u003c/strong\u003e\u003csub\u003e2\u003c/sub\u003e\u003cstrong\u003eO\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"53\"\u003e\n\u003cp\u003e\u003cstrong\u003epH\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e(CaCl\u003c/strong\u003e\u003csub\u003e2\u003c/sub\u003e\u003cstrong\u003e)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u003cstrong\u003eOC\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u003cstrong\u003eTN\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"53\"\u003e\n\u003cp\u003e\u003cstrong\u003eC:N\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u003cstrong\u003eAP\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u003cstrong\u003eCa\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u003cstrong\u003eMg\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u003cstrong\u003eK\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u003cstrong\u003eNa\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; \u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"53\"\u003e\n\u003cp\u003e\u003cstrong\u003eECEC\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u003cstrong\u003eCEC\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"45\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0-15cm\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd colspan=\"3\" width=\"51\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.467a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"53\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e10.800b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd colspan=\"2\" width=\"53\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e85.733a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"15\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.947c\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"53\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.553c\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.352b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.086a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"53\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e11.227b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.251b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.787b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.280a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.177b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.114a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"53\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.626b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.967a\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"45\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e15-30cm\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd colspan=\"3\" width=\"51\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.600b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"53\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e8.933a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd colspan=\"2\" width=\"53\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e85.467a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"15\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.160b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"53\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.553b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.127a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.035a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"53\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.915a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.327a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e2.886a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.473b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.107a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.116a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"53\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.020ab\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.567a\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"45\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e30-60cm\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd colspan=\"2\" width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e7.067c\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd colspan=\"2\" width=\"57\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp; 7.867a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd colspan=\"2\" width=\"53\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e85.067a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"15\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.713a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"53\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.233a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.075a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.025a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"53\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.465a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.209a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e2.377a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.716c\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.089a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.145b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"53\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.928a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.773a\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eMean values with the same letters are not significantly different at 5% probability level by DMRT\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 5: Soil physical and chemical properties as influenced by plot under \u003cem\u003eAcacia senegal \u003c/em\u003eplantation in Jigawa State\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" width=\"0\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u003cstrong\u003ePlot\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u003cstrong\u003eClay\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u003cstrong\u003eSilt\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u003cstrong\u003eSand\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u003cstrong\u003epH\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eH\u003c/strong\u003e\u003csub\u003e2\u003c/sub\u003e\u003cstrong\u003eO\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u003cstrong\u003epH\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e(CaCl\u003c/strong\u003e\u003csub\u003e2\u003c/sub\u003e\u003cstrong\u003e)\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"54\"\u003e\n\u003cp\u003e\u003cstrong\u003eOC\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u003cstrong\u003eTN\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u003cstrong\u003eC:N\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u003cstrong\u003eAP\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u003cstrong\u003eCa\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u003cstrong\u003eMg\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u003cstrong\u003eK\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u003cstrong\u003eNa\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u003cstrong\u003eECEC\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u003cstrong\u003eCEC\u003c/strong\u003e\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e1\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e6.444b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e8.444a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e85.111a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.567c\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.822b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"54\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.207ab\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.127b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.341a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e2.139a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e2.231a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.292a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.088a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.106a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.183a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.344a\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e2\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.556ab\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e8.889a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e85.556a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.189b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.800b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"54\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.1889ab\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.029a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e7.977ab\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.891b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e2.680a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.540b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.138b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.102a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.793a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.478b\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.222a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e11.333b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e84.444a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.500bc\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.111b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"54\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.253b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.027a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e9.772b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.988b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.874b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.660c\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.139b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.111a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.117b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e6.167bc\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e6.444b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e9.111a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e84.444a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.378bc\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.844b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"54\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.162ab\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.035a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.236ab\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.473bc\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.809b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.611bc\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.134b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.148b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.058b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e6.822c\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd width=\"47\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eControl\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.222a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e8.222a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e85.556b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.733a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"49\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e4.322a\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"54\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.111a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.026a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e6.354ab\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e5.154c\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e2.489a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.346a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.123b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e0.159b\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"44\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e3.806a\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd width=\"48\"\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e6.033bc\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eMean values with the same letters are not significantly different at 5% probability level by DMRT\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cem\u003eThe exchangeable cations\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Exchangeable cations investigated in the soil of the plantation and the natural open woodland are calcium (Ca), magnesium (Mg), potassium (K) and sodium (Na). While the calcium and potassium decreased as the soil depth increased, both magnesium and sodium increased as the soil depth increased. The results of decreasing calcium and potassium with soil depth were in agreement with the findings of Oyun (1991) and could be a result of large uptake and storage of Ca and K by the trees.\u0026nbsp; The increase of Mg and Na down the soil depths is in consonance with Tedela (2004) and might be attributed to less utilization of these nutrients by \u003cem\u003eAcacia senegal\u003c/em\u003e. However, the increase of Na along the soil depth could cause soil salinity which is a common phenomenon in dry areas, such as the study area (Oyun, 1991).\u003c/p\u003e\n\u003cp\u003eThe ECEC decreased as the soil depth increased and is low in values. According to Nwachokor \u003cem\u003eet al\u003c/em\u003e (2009), a low ECEC less than 4 cmol/kg implies a low capacity for the soil holding cations against leaching. The CEC of soils commonly range from 3 to 50cmol/kg, comparatively therefore, the soil of the study area had low CEC. The low CEC values could probably be as a result of low organic matter in the soil. This could be attributed to the fact that the soil of arid zones is characterized by low organic matter and clay, oxides and hydroxides of iron and aluminium; all these could lead to poor growth of \u003cem\u003eAcacia senegalensis\u003c/em\u003e in the plantation.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eA comparison of soil nutrient contents of the study area showed that the \u003cem\u003eAcacia senegal \u003c/em\u003eplantation nutrient contents were higher than what were obtained in the natural open woodland. The higher nutrient contents obtained under the plantation plots may be as a result of mineralization resulting from higher number of \u003cem\u003eAcacia senegal \u003c/em\u003etrees which shed their leaves making the leaves available for decomposition thereby increasing the soil organic matter, nitrogen content, increase availability of micro-nutrient (Zn, Mn and Cu) in the soil surface and improved the soil structure. It can therefore be concluded that the decline in soil fertility in the natural open woodland is often as a result of less mineralization of litter which leads to the depletion of the nutrient pool of organic matter.\u003c/p\u003e\n\u003cp\u003eThe study has also shown the influence of trees in soil physical properties which are very important in augmenting the overall capacity of the land to produce. The removal of the vegetative cover from the soil results in increases in bulk density, decreases in porosity and reduction in infiltration rate. This ultimately will reduce land productivity if not properly taken care of. In line with this, researches have demonstrated influence of trees in reversing this problem. This effect was associated with the influence of tree roots and biomass return in terms of mulching or tree litter on the structure and texture of the soils.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eRecommendation\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eJudging from the above, the soil quality and productivity of the natural open woodland can be restored by planting the area up with \u003cem\u003eAcacia senegal\u003c/em\u003e trees or any other tree(s) as trees will promote high biological activities of soil fauna, improve soil organic matter content and replacing the nutrients lost to soil or wind erosion and animal grazing on the land.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate: \u003c/strong\u003e\u003cem\u003eNot applicable\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication: \u003c/strong\u003e\u003cem\u003eNot applicable \u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e: \u003cem\u003eAll data generated or analysed during the study are included in this manuscript.\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e: \u003cem\u003eWe (ATA and ADI) declare that we have no competing interests\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e: \u003cem\u003eThe funding of the project, writing and publication were done by the authors \u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; contribution\u003c/strong\u003e: A\u003cem\u003eTA planned and carried out the research while ADI analysed the data collected and the writing of the publication was jointly done by both authors (ATA and ADI).\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcceptance and Confirmation\u003c/strong\u003e: \u003cem\u003eAll authors of the publication have read and agreed to its content and we are accountable for all aspects of the accuracy and integrity of the publication in accordance with ICMJE criteria.\u003c/em\u003e\u003cem\u003eWe (ATA and ADI) state that the article is original and has not already been published in a journal and is not currently under consideration by another journal. That we agree to terms of the SpringerOpen Copyright and License Agreement.\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; Information\u003c/strong\u003e: \u003cem\u003eATA is a researcher with Forestry Research Institute of Nigeria and hold PhD degree from University of Ibadan, Nigeria in Forest Ecology and Silviculture with specialization in forest soil, plant nutrition and agroforestry. He is a member of many societies both locally and internationally including the following Forestry Association of Nigeria (FAN), Society for Conservation Biology (SCB) and International Society for Tropical Foresters (ISTF).\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eADI is a Senior Lecturer in Forest Biometrics with Ecole de Foresterie Tropicale, Universite Nationale d\u0026Aacute;griculture, Porto-Novo, Benin Republic. Research interests include forest inventory, modelling individual tree characteristics, tree heights, model of aboveground biomass, modelling crowns and roots, quantitative characteristics of forest stands, stand density, site quality, growth yield models, statistically designed experiments in forestry and greenhouse experiments.\u003c/em\u003e\u003c/p\u003e"},{"header":"References","content":"\u003cp\u003eAmerican Water Works Association (AWWA) (1992). Standard method for the \u003cbr /\u003e examination of water and waste water. In: A. E. Greenbag, C. S. Lenore \u003cbr /\u003e and A. D. Eatten (eds.) Washington, D. C.\u003c/p\u003e\n\u003cp\u003eAnderson, J. M and S. J. Ingram 1998. \u003cem\u003eTropical soil biology and Fertility\u003c/em\u003e. A\u003cbr /\u003e handbook of methods. Information Press U. K. 221 Pp.\u003c/p\u003e\n\u003cp\u003eBelsky, A. J.; R. G. Amudson; J. M. Duxbury; S. J. Riha; A. R. Ali and \u003cbr /\u003e S. M. Mwonga 1989. The effects of trees on their physical, chemical \u003cbr /\u003e and biological environments in a semi-arid savanna in Kenya. \u003cem\u003eJ. of \u003cbr /\u003e\u003c/em\u003e \u003cem\u003eApplied\u003c/em\u003e\u003cem\u003eEcol. \u003c/em\u003e26: 1005-1024.\u003c/p\u003e\n\u003cp\u003eBill, M. 2007. Trees and their energy transactions. \u003cem\u003eThe Overstory, \u003c/em\u003eNo.\u003cbr /\u003e 92.Agroforestry Net Inc., Holualoa, Hawaii, USA. 10 Pp.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eBray, R. H. and L. T. Kurtz 1945. Determination of total organic and available \u003cbr /\u003e forms of phosphorous in soils. \u003cem\u003eSoil Science \u003c/em\u003e59: 39-45.\u003c/p\u003e\n\u003cp\u003eBremner, J. M., 1982. Inorganic nitrogen In: Page, A. L.; Miller, R. H. and \u003cbr /\u003e Keeney, D. R. (ed). Methods of soils analysis, Part 2. \u003cem\u003eAmer. Soc. of Agron.\u003cbr /\u003e\u003c/em\u003e \u003cem\u003eMadison.\u003c/em\u003e 595-624\u003c/p\u003e\n\u003cp\u003eBurke, I. C., W. K. Lauenroth; M. A.Vinto; P. B. Hook; R. H. Kelly; H. E. Epstein; \u003cbr /\u003e M. R. Aguiar; M. D. Robles; M. O. Aguilera and R. A. Gill 1998. \u003cbr /\u003e Plant-Soil interaction in temperate grasslands. \u003cem\u003eBiogeochemistry \u003c/em\u003e42: 121-\u003cbr /\u003e 143.\u003c/p\u003e\n\u003cp\u003eCarter, M. R.; D. A. Angers; E. G. Gregorich and M. A. Bolinder 1997. Organic\u003cbr /\u003e carbon and nitrogen stocks and storage profile in cool, humid soils of eastern\u003cbr /\u003e Canada, \u003cem\u003eCanadian J. of Soil Sc.\u003c/em\u003e 77: 205-210.\u003c/p\u003e\n\u003cp\u003eChapman, H. D. 1965. Cation exchange capacity. In C. A. Black (ed).Methods\u003cbr /\u003e of soil analysis. Part 2, \u003cem\u003eAgron. No 9, ASA Madison Wisconsin, USA. \u003c/em\u003e891- \u003cbr /\u003e 901.\u003c/p\u003e\n\u003cp\u003eIITA, 1979. Selected methods for soil and plant analysis. International Institute \u003cbr /\u003e of Tropical Agriculture, Ibadan.\u003cem\u003e Manual, serie\u003c/em\u003es No 1: 35 Pp.\u003c/p\u003e\n\u003cp\u003eJackson, R. B.; J. Canadell; J. R. Ehleringer; H. A. Mooney; O. E. Sala and \u003cbr /\u003e E. D. Schulze 1996. A global analysis of root distributions for terrestrial\u003cbr /\u003e biome. \u003cem\u003eOecologia \u003c/em\u003e108: 389 \u0026ndash; 411.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eKessler, J. J. 1992. The influence of Karite (V\u003cem\u003eitellaria paradoxa\u003c/em\u003e) and nere \u003cbr /\u003e (\u003cem\u003eParkia\u003c/em\u003e\u003cem\u003ebiglobosa)\u003c/em\u003e trees on sorghum production in Burkina Faso. \u003cbr /\u003e \u003cem\u003eAgroforestry Systems\u003c/em\u003e 17: 97-118.\u003c/p\u003e\n\u003cp\u003eLechisa, T.; C. Achalu and A. Alemayehu 2014. Dynamics of soil fertility as\u003cbr /\u003e influenced by different land use systems and soil depth in west Show zone\u003cem\u003e,\u003cbr /\u003e\u003c/em\u003e Gindeberet, District, Ethiopia. \u003cem\u003eJournal of Agriculture, Forestry and\u003cbr /\u003e\u003c/em\u003e \u003cem\u003eFisheries\u003c/em\u003e 3(6): 489-494.\u003c/p\u003e\n\u003cp\u003eMohamed, A. G. 2005. Improvement of traditional \u003cem\u003eAcacia senegal\u003c/em\u003e agroforestry:\u003cbr /\u003e Ecophysiological characteristics as indicators for tree-crop interaction on\u003cbr /\u003e sandy soil in western Sudan. \u003cem\u003eA Paper presented for discussion at the\u003cbr /\u003e\u003c/em\u003e \u003cem\u003eUniversity of Helsinki on \u003c/em\u003e4 March, 2005, 98 Pp.\u003c/p\u003e\n\u003cp\u003eNAS, 1979. \u003cem\u003eAcacia auriculiformis\u003c/em\u003e. Report of an Ad Hoc Panel of the Advisory\u003cbr /\u003e Committee on Technology Innovation, NAS Washington, D. C. 165-171.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;Nwachokor, M. A.; F. O. Uzu and W. A. Molindo 2009. Variations in\u003cbr /\u003e physicochemical properties and productivity implications for four soils in \u003cbr /\u003e the derived savanna of Southern Nigeria. \u003cem\u003eAmerican-Eurasian J. of \u003c/em\u003e\u003cem\u003e\u0026nbsp;\u003cbr /\u003e \u003c/em\u003e\u003cem\u003eAgronomy\u003c/em\u003e 2 (3): 124-129.\u003c/p\u003e\n\u003cp\u003eOdunze, A. C. and J. O. Ogunwole 2002\u003cem\u003e. Proven on-farm soil conservation \u003cbr /\u003e\u003c/em\u003e \u003cem\u003etechnology\u003c/em\u003e\u003cem\u003efor sustainable fertility management in northern Nigeria\u003c/em\u003e.\u003cbr /\u003e Fed. Min of Agric and Rural Development and FAO. 1-2 Pp\u003c/p\u003e\n\u003cp\u003eOgunyebi, L. A. 2008. \u003cem\u003eNutrient dynamics associated with litterfall and \u003cbr /\u003e\u003c/em\u003e \u003cem\u003emineralization\u003c/em\u003e\u003cem\u003e o\u003c/em\u003e\u003cem\u003ef\u003c/em\u003e\u003cem\u003eGmelina arborea\u003c/em\u003e\u003cem\u003eRoxb. in a lowland rain forest\u003c/em\u003e. A \u003cbr /\u003e PhD Thesis submitted to Dept. of Forest Resources Management, \u003cbr /\u003e Faculty of Agric. and Forestry, University of Ibadan, Nigeria, 189 Pp.\u003c/p\u003e\n\u003cp\u003eOyun, M. B. 1991\u003cem\u003e. Effect of soil salinity on three selected savanna tree species in\u003cbr /\u003e\u003c/em\u003e \u003cem\u003eBauchi State, Nigeria\u003c/em\u003e. A M.Sc. Thesis submitted to Dept. of Forest \u003cbr /\u003e Resources Management, University of Ibadan, Nigeria.\u003c/p\u003e\n\u003cp\u003eRowell, D. L. 1994. \u003cem\u003eSoil science: Methods and applications.\u003c/em\u003e Addison Wesley\u003cbr /\u003e Longman Singapore Publishers Ltd., England U. K. 350 Pp.\u003c/p\u003e\n\u003cp\u003eRussell, E. W., 1973. \u003cem\u003eSoil conditions and plant growth.\u003c/em\u003e Longman Group Ltd., N.\u003cbr /\u003e Y. 284-326 Pp.\u003c/p\u003e\n\u003cp\u003eSamndi, A. M., 2005. \u003cem\u003eCharacterization and classification of soils under long-\u003cbr /\u003e\u003c/em\u003e \u003cem\u003eterm Teak\u003c/em\u003e\u003cem\u003e(Tectona grandis) plantation in Southern Guinea savanna of\u003cbr /\u003e\u003c/em\u003e \u003cem\u003e\u0026nbsp;Nigeria.\u003c/em\u003e A PhD Thesis submitted to Dept. of Soil Science, A. B. U. \u003cbr /\u003e Zaria, Nigeria. 280 Pp. Unpublished.\u003c/p\u003e\n\u003cp\u003eSchlesinger, W.; J. A. Raikes; A. E. Hartley and A. F. Cross 1996 . On the spatial\u003cbr /\u003e pattern of soil nutrients in desert ecosystems. \u003cem\u003eEcology \u003c/em\u003e77: 364-374.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eShankaranaraya, K. A. and L. W. Harsh 1986. \u003cem\u003eAgroforestry in the arid zones of \u003cbr /\u003e India. \u003c/em\u003eContibution No. 22 of the series of agroforestry system\u003cbr /\u003e descriptions under, ICRAF\u0026rsquo;s agroforestry system project (USAID) 1-\u003cbr /\u003e 22 Pp.\u003c/p\u003e\n\u003cp\u003eSoto, B. and F. Diazfierroz 1993. Interaction between plant ash leachates and\u003cbr /\u003e soil. \u003cem\u003eInternational \u003c/em\u003e\u003cem\u003eJournal of Wildlife\u003c/em\u003e, 3:207-216.\u003c/p\u003e\n\u003cp\u003eSpore, 2001. New network, by gum. \u003cem\u003eSpore \u003c/em\u003eNo 91\u003cem\u003e, CTA, Wageningan, \u003cbr /\u003e\u003c/em\u003e \u003cem\u003eNetherlands. \u003c/em\u003e16.\u003c/p\u003e\n\u003cp\u003eTedela, T. H. 2004. \u003cem\u003eRoot biomass and nutrient distribution study in an Eucalyptus\u003cbr /\u003e\u003c/em\u003e \u003cem\u003e\u0026nbsp;camaldulensis plantation in Ethiopia.\u003c/em\u003e A M.Sc. thesis submitted to\u003cbr /\u003e University of Natural Resources and Applied Life Science, Vienna.\u003cbr /\u003e 106Pp. Unpublished.\u003c/p\u003e\n\u003cp\u003eWalkley, A. and I. A. Black 1934. An examination of the Degtjiareff method for\u003cbr /\u003e determining soil organic matter and a proposed modification of \u003cbr /\u003e chromic and titration method. \u003cem\u003eSoil Sci. \u003c/em\u003e37: 29-38\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Acacia senegal, plantation, soil nutrients, trees","lastPublishedDoi":"10.21203/rs.3.rs-135012/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-135012/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eBackground\u003c/p\u003e\u003cp\u003e\u003cem\u003eAcacia senegal\u003c/em\u003e (L) Wild\u003cem\u003e \u003c/em\u003eknown as gum Arabic tree, is a nitrogen fixing tree and a drought resistant species with potentials to improve infertile soils is planted in Sahel zone of Jigawa State, Nigeria for the production of gum arabic. However, there is dearth of information on the soil physico-chemical properties under plantation.\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u003c/p\u003e\u003cp\u003eMethods\u003c/p\u003e\u003cp\u003eSoil samples were collected from four 30 x 30m plots in the plantation and another plot in open woodland (control). In each plot, three replicate soil samples were taken from 0-15cm, 15-30cm and 30-60cm soil depths analyzed for micro and macronutrients, while soil acidity was determined both in water and 0.01M CaCl\u003csub\u003e2\u003c/sub\u003e.\u003c/p\u003e\u003cp\u003eResults\u003c/p\u003e\u003cp\u003eThe general soil texture of the plantation is loamy sand but with slight textural differentiation under the open woodland. Results indicated that physico-chemical properties of soils under the plantation were significantly different at P \u0026lt; 0.05 compared with the control. The mean soil bulk density ranged from 1.6g/cm\u003csup\u003e3\u003c/sup\u003e in the plantation to 1.8g/cm\u003csup\u003e3\u003c/sup\u003e in the open woodland. The high values of soil bulk density might be ascribed to loss of organic matter as a result of soil erosion and animal grazing which are common occurrences. \u003c/p\u003e\u003cp\u003eConclusion\u003c/p\u003e\u003cp\u003eFrom the result of the study soil physico-chemical properties under the plantation are high and have more beneficial effects on the trees unlike the open woodland.\u0026nbsp;\u003c/p\u003e","manuscriptTitle":"Physico-Chemical Properties of Soil Under Acacia Senegal (L) Willd Plantation in Sahel Zone of Nigeria","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2020-12-28 21:50:11","doi":"10.21203/rs.3.rs-135012/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"94c03837-08d4-4433-8282-8b958bb3b624","owner":[],"postedDate":"December 28th, 2020","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":1646263,"name":"Forestry"},{"id":1646264,"name":"Chemical Biology"},{"id":1646265,"name":"Plant Physiology and Morphology"}],"tags":[],"updatedAt":"2020-12-28T21:50:12+00:00","versionOfRecord":[],"versionCreatedAt":"2020-12-28 21:50:11","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-135012","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-135012","identity":"rs-135012","version":["v1"]},"buildId":"DiO0y1XJrWGSkZWLOoVa_","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}