Earthworm Population and Diversity Enhanced Under Conservation Management Practices in Intensified Rice-Fallow System of South Asia

Abstract

The study was conducted in eastern India's rainfed lowland rice-fallow ecosystems. It aimed to assess the impact of different crop establishment methods on system productivity, earthworm activity and diversity, and soil quality parameters for long-term sustainability. Three distinct crop establishment methods viz. zero-till direct-seeded rice (ZTDSR), conventional-till direct-seeded rice (CTDSR), and transplanted puddle rice (TPR), were employed in conjunction with various crop residue management strategies. The TPR and conventional tillage methods consistently outperformed ZTDSR in terms of grain yield and recorded a 28.9% and 15.4% higher grain yield than ZTDSR and CTDSR, respectively. However, TPR had a detrimental impact on the performance of all winter crops, resulting in a lower grain yield by 29% and 44% than CTDSR and ZTDSR, respectively. The incorporation of a legume or oilseed during the fallow period in the winter season in a rice-fallow system resulted in an increase in system productivity from 5.44 to 9.54 Mg ha−1 (75% increase) demonstrating its potential to boost the food security of the region. Importantly, the study also quantified the critical role of conservation agriculture (CA) practices in enhancing soil health and earthworm activity. The CA-based production systems (CTDSR and ZTDSR) noted a 35.6%, 27.3%, 91.9%, and 73.4% higher earthworm casting, burrows count, total earthworm count, and biomass, respectively, over the TPR system. The TPR production system was associated with increased parameters of soil cracking, including length, width, depth, and volume compared to CA-based management systems. In conclusion, adopting CA-based practices and integrating short-duration pulses and legumes can enhance crop productivity, soil health, and earthworm populations, supporting food and nutritional security in India's rice-fallow regions and similar South Asian agro-ecotypes. © 2025 John Wiley & Sons Ltd.