Replacement of rice-wheat cropping system with alternative diversified systems concerning crop productivity and their impact on soil carbon and nutrient status in soil profile of north-west India

Abstract

The depth-wise depletion of soil organic carbon (OC), macro, micro, and secondary nutrients under the rice-wheat system has resulted in multi-nutrient deficiencies and a decline in crop productivity, emphasizing the replacement of rice-wheat with alternate cropping systems like maize-wheat, cotton-wheat, soybean-wheat, and moongbean-wheat to restore soil fertility and productivity. Long-term investigations (since 2016) revealed that there was a depth-wise decline in pH, EC, OC, and nutrients in soil profile (Udic Ustrochept, Inceptisols) among different cropping systems. The practice of deep-rooted cropping systems (maize-wheat and cotton-wheat) led to maximum OC, soluble calcium, and magnesium, while legume-based systems (especially soybean-wheat) led to maximum available phosphorus (30.86 kg ha−1), boron (0.49 mg kg−1), and DTPA-zinc (1.82 mg kg−1) in soil profile (0–120 cm). This system also led to the maximum surface soil OC, available phosphorus, soluble magnesium, DTPA-zinc, and boron. From the production point of view, soybean-wheat system (115.65 q ha−1) led to higher system grain productivity as compared to rice-wheat system (109.60 q ha−1). Therefore, the practice of alternative cropping systems like soybean-wheat and cotton-wheat helps in the build-up of nutrient status by playing a pivotal role in influencing the surface and depth-wise distribution of organic carbon and nutrients in the soil.