Variation of Physico-Chemical Properties among Different Soil Orders under Different Land Use Systems of the Majha Region in North-Western India

The impact of different soil orders and land use systems on the distribution of physico-chemical properties is the most critical matter to address in order to maintain sustainable agricultural production. Hence, the present investigation was carried out to study the variation in the physico-chemical characteristics of soil in diverse land use systems (LUSs), i.e., agriculture, horticulture, and forestry, under major soil orders (entisol, inceptisol, and alfisol) in the Majha region of Punjab. A total of 225 depth-wise (at 0–20 cm, 20–40 cm, 40–60 cm, 60–80 cm and 80–100 cm) soil samples were collected from three land-use systems under different soil orders. The mean values of the physico-chemical properties ranged from 6.80–7.50, 7.64–8.34 and 6.94–7.87 for pH; 0.13–0.42, 0.19–0.54 and 0.19–0.46 dS m −1 for EC; 0.14–0.99, 0.21–0.69 and 0.15–0.72% for OC; 0.75–2.07, 1.07–3.32 and 0.93–2.29% for CaCO 3 ; 7.77–41.84, 10.56–40.23 and 7.24–39.51 kg ha −1 for P; and 98.37–334.68, 94.51–230.18 and 93.01–367.39 kg ha −1 for K under different land uses in soil orders entisols, inceptisols and alfisols, respectively. Soil parameters including pH, CaCO 3 , and phosphorus (P) distribution differed significantly among soil orders; however, soil EC, organic carbon (OC) and available potassium (K) did not. The inceptisols under the agricultural land use system (ALUS) had the highest soil pH, EC, and CaCO 3 values. The highest soil OC content was found in entisols under forest land use systems (FLUS), followed by horticultural land use systems (HLUS). The highest values of soil-available phosphorous (P) were found in FLUS under inceptisols, while the highest amounts of soil-available potassium (K) were found in entisols and alfisols under ALUS and FLUS, respectively. Thus, the distribution of physico-chemical properties under different LUSs in each soil order is highly variable and does not follow any particular trend. In general, soil properties such as OC, P, and K content decreased with an increase in soil depth, while pH and CaCO 3 values increased with depth in all land uses and soil orders. There was a positive correlation between soil OC and EC, as well as available P and K in the soils investigated. The available P and K are negatively correlated with soil pH and CaCO 3 content in the soil. The principal component analysis (PCA) revealed that soil pH and OC were the most variable soil parameters, which influence the availability of other physico-chemical properties under different soil orders and land use systems. Therefore, it is suggested that the land use systems play an important role in the distribution of physico-chemical properties of soil in different soil orders. The results of the study will help students, researchers, and agricultural management staff in managing different land uses for maintaining soil fertility and productivity in alluvial soils of North-western India.