Abstract
In order to assess the changes in soil chemical properties’ resulting from conversion of forest to other agricultural land uses a study was conducted in Okomu Forest Reserve (Nigeria). Five soil samples collected from top and sub soils of marked points within the undisturbed forest, farmland, cocoa plantation, oil palm plantation and rubber plantation were analyzed for pH, organic carbon, total nitrogen, available phosphorus, exchangeable acidity, sodium, potassium, calcium and magnesium. The results showed variations in all chemical parameters across the land use types with soil depths (top and sub soils). Soil pH ranged from 4.88 (in the cocoa plantation subsoil) to 6.75 (in the forest top soil). Soils (top and sub soils) of the rubber plantation, forest and cocoa plantation had the highest stock of soil organic carbon (SOC), N and exchangeable Na respectively. Available P was highest in the top soil of the rubber plantation and sub soil of the farmland. Exchangeable Ca and Mg were highest in the top soil of the forest and sub soil of the rubber plantation. Exchangeable K and C:N was highest in the farmland top soil and cocoa plantation sub soil. Relationship among the chemical parameters varied with soil depth. Conversion of forest and cocoa plantation resulted in the highest decline (55.78% and 44.40%) in soil N. There is the need to regulate the conversion of natural forests to agricultural lands and plantations as conserve the nutrient cycling processes.
Highlights
Land use changes have remarkable effects on the dynamics of soil properties (Ozgoz et al, 2013)
Available phosphorus concentration was generally highest in the top soil of the rubber plantation (14.20 mg kg-1) while the farmland had the highest P in the sub soil (10.12 mg kg-1)
Soil pH in the acidic range in the cocoa plantation is in line with earlier report by Ololade et al (2010) for cocoa plantation in Ile-Oluji, Ondo State. pH of the top soil in this study tend to increase with exchangeable K, Ca, Mg and organic carbon
Summary
Land use changes have remarkable effects on the dynamics of soil properties (Ozgoz et al, 2013). A change from forest cover to cultivated land may hinder addition of litter that enhances nutrient content of soils (Ozgoz et al, 2013), increase rates of erosion (Biro et al, 2013), loss of soil organic matter and nutrient (Saha and Kukal, 2015), and accelerate rate of soil degradation (Barua and Haque, 2013). This process, in turn, leads to a decline in soil fertility and loss of biological activity and diversity (Yao et al, 2010). If the canopy is not dense enough or well developed, little nutrients return to the soil as well as large quantities of nutrient will be removed from the soil surface during periods of heavy rainstorm when the soil is saturated
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
