Grain Production and Household Demand Under Water and Soil Constraints in Northeast China

An increase in grain production relative to household demand can reflect production growth or demand contraction. We examined these accounting pathways and resource indicators across 36 prefectures in Northeast China, using six snapshots from 2000 to 2023 and a comparison based on the inputs for 2020 and 2023. Budyko water yield, the Revised Universal Soil Loss Equation (RUSLE) and Shapley decomposition were combined with sensitivity analysis and ensembles incorporating model residuals. Estimated household grain demand declined in 34 prefectures under baseline inputs, with counts ranging from 9 to 36 under independent ±10% population and consumption perturbations. Production exceeded grain consumption at home in all 36 prefectures in 2023 throughout these perturbations. Baseline resource screening identified three prefectures with water pressure, eight with relatively high erosion and one with both flags. At fixed baseline thresholds, an ensemble incorporating water model residuals changed an average 21.7% of baseline categories per draw. Recent associations between changes in the grain ratio and resource indicators had intervals spanning zero. The framework distinguishes the accounting sources of an improving household grain balance and identifies priorities for local water and soil assessment.