Rotation reshapes sustainable potato production in dryland by reducing environmental footprints synergistically enhancing soil health

Sustainable agricultural production encounters significant challenges in balancing economic returns with environmental sustainability, particularly in the ecologically fragile dryland regions of Northwest China. This study employed life cycle assessment (LCA) and comprehensive evaluation index (CEI) to identify the optimal cropping system among potato continuous cropping (PC), wheat/green manure-potato (WgP), pea/green manure-potato (PgP), and wheat/green manure-pea/green manure-potato (WgPgP) in the study region. Furthermore, the non-dominated sorting genetic algorithm II (NSGA-II) was used to optimize regional cropping structure. The results indicated that crop rotations improved the soil health index by 13.1%–63.4%, increased the potato yield by 15.0%–38.2%, enhanced net economic benefits (NEB) by 30.6%–41.9%, and boosted net ecological economic benefits (NEEB) by 36.3%–47.6% compared to PC. Additionally, crop rotations reduced water consumption by 11.2%–26.1% and greenhouse gas (GHG) emissions by 33.6%–59.3%, while improving the potato nutrient use efficiency by 12.8%–38.4%. The CEI rankings indicated that PgP (41.5%) was the highest, followed by WgPgP (33.2%), WgP (17.3%), and PC (9.7%). Expanding the PgP rotation in Northwest China could significantly reduce nutrient and water inputs, decrease GHG and reactive nitrogen (Nr) emissions, and enhance productivity and profitability. This study provides a practical pathway for sustainable food production in dryland agricultural regions by emphasizing the pivotal role of crop rotation in improving soil health and mitigating GHG and Nr emissions.