Abstract
Problem statement: Land use practice leads to changes in the physico-chemical properties of soils, such as Soil Organic Carbon (SOC), Cation Exchange Capacity (CEC) and Soil Aggregate Stability (SAS) that cause soil erosion. Approach: Merek catchment, Iran suffers from land degradation due to poor land use practice. A study was carried out with the objectives: (i) to determine soil nutrient status in different agro-ecological zones in Merek catchment; and (ii) to evaluate the influence of land use practices on SOC, CEC and SAS. Results: It was found that soil texture was silty and clay, while soil reaction was alkaline (pH was 7.75). The respective amount of carbonates was 32 and 36% in the top-soil and sub-soil respectively, indicating high level of alkalinity in the soils of the study area. The mean SAS of the surface soil layer for agriculture, rangeland and forest was 53, 61 and 64%, respectively with its mean in the topsoil of agriculture is significantly lower (P≤0.05) than the other zones. SOC level in the agriculture, rangeland and forest were 1.35, 1.56, 2.14% in the topsoil and 1.03, 1.33 and 1.45%, in the subsoil of the respective areas. The results of t-test and ANOVA analyses showed that SOC means are significantly different from each other within soil depth and among agro-ecological zones. The CEC in the agriculture, rangeland and forest areas were 25.8, 24.6 and 35.1 cmol ckg -1 for the top-soil and 31.1, 26.8 and 26.9 cmol ckg -1 in the sub-soil, respectively. All the above changes are due to the negative effects of agricultural activities. Conclusion: Improper tillage practice (up-down the slope), conversion of the rangeland and forest to rain-fed areas, crop residue burning, over grazing and forest clearance contribute to reduction in SOC and SAS in the Merek catchment, Iran.
Highlights
Land use practices and land use shifting lead to soil erosion, leading to negative changes in the soil physicochemical properties, especially Soil Aggregate Stability (SAS), Soil Organic Carbon (SOC) and Cation Exchange Capacity (CEC)
Fragmented forests which are more sensitive to soil erosion because of topography and geological properties
Agricultural activities are characterized by continued annual crop cultivation, crop residue burning, overutilization of chemical fertilizes and up to down the slope tillage practice
Summary
Land use practices and land use shifting lead to soil erosion, leading to negative changes in the soil physicochemical properties, especially Soil Aggregate Stability (SAS), Soil Organic Carbon (SOC) and Cation Exchange Capacity (CEC). Reduction of SOC and increasing the degradation problem due to improper tillage practices, soil erodibility is related to crop residue burning.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
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.
