Identification of the productive, economically sound, and energy-cum-carbon efficient system for higher agricultural sustainability in the North Eastern Himalayas

• Organic and integrated practices enhanced rice grain and protein yield in sunken beds. • Okra-carrot and okra-tomato rotation with integrated practices registered the highest productivity and net returns in raised beds. • Okra-French bean with organic and integrated practices positively influenced soil health. • Organic practices offered the highest energy efficiency and a lower carbon footprint. • Hence, the okra-carrot, okra-tomato, and okra-French bean sequences are promising options for diversifying rice-fallow in the North Eastern Himalayas. Identifying a suitable production system is crucial for ensuring long-term food security and climate resilience in the North Eastern Himalayas of India. Thus, the field experiment on organic, inorganic, and integrated nutrient management (INM) was evaluated to assess its impact on productivity, profitability, and sustainability under raised and sunken beds (RSB). In sunken beds, Lampnah produced the highest grain (4.23 Mg ha -1 ) and protein yield (330 kg ha -1 ). While, in raised beds, the okra-carrot system with INM showed the highest system productivity and sustainable yield index (SYI). Further, the highest net return (857 $ ha -1 ) was recorded in Lampnah, and 100 % organic had a 5.56–6.52 % grater return than the others. Similarly, in raised beds had the highest production cost was incurred in the okra-potato system (1394 $ ha -1 ), while okra-carrot and INM systems showed the highest net returns (4885 $ ha -1 and 4477 $ ha -1 , respectively). Likewise, the energy use efficiency (EUE), and energy output (EO) were highest in 75 %, and 100 % organic systems in sunken beds, and in okra-carrot and 100 % organic systems in raised beds. Further, 100 % organic treatments also improved the soil organic carbon (SOC) along with a greater carbon sustainability index (CSI), and carbon use efficiency (CUE). Thus, the study clearly demonstrates that, the integration of organic, and INM under RSB improves productivity, profitability, carbon storage, and environmental sustainability, contributing to food security in the North Eastern Himalayas.