Ludhiana: A long-term study by agricultural scientists in Punjab has delivered a clear verdict: the traditional rice-wheat cropping cycle is degrading soil health, and the inclusion of legumes, fodder, and green manure is essential for agricultural sustainability in north-western India.The research, published in the Journal of Soil and Water Conservation, was conducted by K B Singh (director, PAMETI) and Tejinder Kaur (Punjab Agricultural University). It compared ten different cropping systems to evaluate their long-term impact on soil fertility and structure.The Problem with Cereal MonocroppingThe study highlights that the dominant rice-wheat system relies on intensive tillage and “puddling” (churning wet soil for rice). These practices have led to soil compaction (higher bulk density makes it harder for roots to penetrate), reduced porosity (restricted air and water movement within the soil), and loss of organic carbon (rice-wheat systems recorded the lowest organic carbon levels, a key indicator of fertility).The Benefits of DiversificationIn contrast, systems incorporating maize, basmati rice, cowpeas, mungbeans, and berseem showed significantly improved Soil Quality Index (SQI) values. Key improvements included superior soil structure (better soil aggregation and water-stable aggregates), enhanced moisture retention (higher water-holding capacity, making crops more resilient to dry spells), and improved hydraulic conductivity (better water movement through the soil due to increased organic matter).Economic and Ecological GainsK B Singh has emphasised that the benefits of diversification extend beyond the soil. “Growing fodders also augments farmers’ income directly and indirectly, especially for those with dairy farms,” he said. The researchers advocate for an integrated farming system, which combines green manuring (planting crops specifically to be plowed back into the soil) and leguminous plants (naturally fixing nitrogen in the soil), besides horticulture and dairy (diversifying into fruits, vegetables, and livestock to create a self-sufficient and resilient farm ecosystem).
