Depth-wise Variation in Soil Properties and Nutrient Status under Integrated Farming System in the Northwestern Himalayan Region

Abstract

A field study was carried out at the decade-old, one-hectare Integrated Farming System (IFS) research model of the AICRP-IFS, Farming System Research Centre, Sher-e-Kashmir University of Agricultural Sciences and Technology of Jammu (SKUAST-Jammu), Chatha and at an adjoining farmer's field representing the existing farming system (EFFS), to assess the depth-wise (0–15, 15–30, 30–45 and 45–60 cm) distribution of soil physico-chemical properties and available nutrient status under twelve land use systems of the IFS model vis-à-vis EFFS. Soil texture was clay loam across all land uses and depths, with sand as the dominant separate (55.51–68.65 % at the surface) and no consistent depth-wise trend in sand, silt or clay fractions. Bulk density increased with depth in all land uses (1.25–1.33 g cm-3 at 0–15 cm to 1.69–1.74 g cm-3 at 45–60 cm) and was significantly lowest under boundary plantation. Soil reaction was slightly alkaline to alkaline (pH 7.64–8.30) and increased with depth, being significantly lower under horticulture and boundary plantation than under the crop block and EFFS, while electrical conductivity did not differ significantly among land uses and declined with depth. Available nitrogen, phosphorus and potassium, along with DTPA-extractable Fe, Mn, Zn and Cu, were all significantly higher under boundary plantation intercropped with turmeric (up to 307.51 kg N ha-1, 22.68 kg P ha-1, 140.35 kg K ha-1, 31.45 mg Fe kg-1, 31.55 mg Mn kg-1, 1.48 mg Zn kg-1 and 1.01 mg Cu kg-1 at the surface) and consistently lowest under EFFS, with all nutrients declining with depth. DTPA-Zn fell below its critical limit beyond 30 cm depth in most land uses except boundary plantation and the fodder block. The results indicate that decade-long integration of horticulture, fodder and boundary plantation components under IFS builds up soil fertility and improves the nutrient status of soil more effectively at all depths than a mono-cropped farmer's system.