ABSTRACT
Eight integrated crop management (ICM) practices were evaluated for six years consecutively, which are ICM1&2: ‘business-as-usual’ (conventional transplanted rice fb flatbed wheat), ICM3&4: conventional direct seeded rice (DSR) fb furrow irrigated raised-bed wheat without residues, ICM5&6: conservation agriculture (CA)-based zero-tilled (ZT) DSR fb ZT wheat with the wheat and rice residues and ICM7&8: CA-based ZTDSR fb ZT wheat with the wheat, mungbean and rice residues. ICM7-8 produced 9.6–16.4% and 9.4–9.9% greater system rice equivalent yield (REY) than the ICM1-4 and ICM5-6, respectively. Residue-retained CA-based ICM5-8 had 23.2% and 58.5% greater N and P balance, respectively, than the residue removed (ICM1-4); subsequently, negative K balance (–53 to –115.5 kg ha−1) was recorded in ICM1-4. ICM5-8 consumed ~60-78% of total energy and produced the highest energy output (Eo) in rice (11.5–12.6%)/wheat (7.3–13%) than ICM1-4. In contrast, ICM1-4 had a greater energy use efficiency (EUE) compared to ICM5-8 due to lesser energy input (EI) through indirect renewable sources. At a soil depth of 0.0–0.45 m, the ICM5-8 contributed 7.9% and 20.2% greater active and passive OC pools over the ICM1-4. Thus, CA-based ICM in rice-wheat rotation (RWR) could be a possible substitute for the positive nutrient balance, system yields and energy and carbon dynamics.
Acknowledgements
We acknowledge the ICAR-Indian Agricultural Research Institute (IARI) and the Indian Council of Agricultural Research (ICAR), New Delhi, for the financial support and necessary facilities. Thanks are also to the Heads of Agronomy, Microbiology and Soil Science, ICAR-IARI for providing the necessary field and laboratory facilities during the experimentation.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Supplementary material
Supplemental data for this article can be accessed online at https://doi.org/10.1080/03650340.2022.2079635