Diverse land use systems differentially affect soil quality index in reclaimed sodic soils of Western Indo-Gangetic plains of India
摘要
The study evaluated five land use systems: (1) conventional agricultural system (LU-CA; puddled transplanted rice succeeded by conventional tilled wheat), (2) partial conservation agriculture system (LU-PCA; zero-tillage direct-seeded rice succeeded by zero-till wheat with 1/3rd crop residue retention), (3) horticultural system (LU-LHS; Litchi plantation), (4) agroforestry system (LU-MAS; Melia trees + wheat intercrop), and (5) plantation system (LU-EPS; eucalyptus plantation) for their impact on soil health in reclaimed sodic soils. Soil samples from four depths (0–15, 15–30, 30–45 and 45–60 cm) were analysed for physico-chemical, and biological properties to develop a soil quality index (SQI). Soil bulk density (BD) was highest in the Melia-based agroforestry system, while soil penetration resistance (SPR) was highest under the conventional system. In comparison, the partial conservation agriculture system exhibited the lowest values for both BD and SPR, indicating improved soil physical conditions under this management practice. The eucalyptus-based system exhibited the highest soil organic carbon (SOC), SOC stock, macronutrients (N, P, K), and biological properties (microbial biomass carbon, microbial biomass nitrogen, and alkaline phosphatase). Relative to LU-CA, LU-PCA increased SOC stock by 22.9%. The highest SQI (0.81) was in eucalyptus plantation, followed by lichi-based horticulture (0.58), while conventional system had the lowest (0.17). Higher SQI in EPS and LHS resulted from greater SOC, microbial biomass, and lower pH, BD and SPR, enhancing soil health. Overall, the findings highlight that perennial systems such as eucalyptus plantations and litchi orchards enhance soil health, quality and organic carbon, offering a sustainable land management strategy for reclaimed sodic soils.