Diverse nutrient management strategies for achieving a sustainable energy-food-environment nexus in rice-rice production systems

The double rice (rice followed by rice) production systems are often associated with poor resource use efficiency and resource degradation and the long-term sustainability of such cropping systems is uncertain in virtue of global climate change. This research links the complex relationship of energy budgeting, carbon input–output, and water use for sustainable rice production. Along with this, a novel concept of “net ecosystem economic budget (NEEB)” was taken to examine the ecological and economic viability of such cropping systems. The current study evaluated the long-term rice-rice cropping system (2006–2019) with different fertilizer management options on rice productivity, resource use efficiency (energy, carbon, and water), and net ecosystem economic budget. Farmyard manure (an organic amendment; FYM) combined with NPK fertilizer application (NPK + FYM) improved the rice yield by 34–38% compared to sole NPK application in both rice crops. The NPK + FYM application improved the energy use efficiency, net energy, output energy, energy intensity, and energy productivity by 13.6%, 34%, 37.3%, 39.3%, and 13.6% (wet season rice crop), and 20%, 39.7%, 44.6%, 29.6%, 17.7% (dry or winter season rice crop) than the sole application of inorganic sources. NPK treatments required 15.2% (wet season) and 19% (dry season) higher energy than NPK + FYM to produce a kg of grain, but NPK+FYM had a 16.7–18.4% lower C-foot print and 35.2% higher C-sustainability index. In wet and dry seasons, NEEB ranged from 95 to 392% in NPK + FYM applied plots compared to NPK application. The resource use indicators (specific energy, energy productivity, CER, and CSI) in other fertilizer application scenarios such as 150%NPK, NPK + Lime, and NPK + Zn were similar to NPK + FYM applications in many cases, but they cannot be considered as sustainable production practices in virtue of lower soil organic carbon (SOC) content and decline in productivity over the years (inference from LTFE). Thus, the adoption of a balanced dose of NPK with FYM was the most feasible alternative to get high productivity, resource use efficiency, and profit in a rice-rice system in Eastern India without compromising long-term sustainability. The above findings can support the policymakers for the popularization of climate-smart sustainable production practices for intensive rice-rice cropping systems in the majority tract of South Asia. If FYM is scarce in the region, alternative organic sources such as intercropping with sesbania, green leaf manuring, or the use of summer pulses can be advocated to maintain the SOC. Graphical abstract