Quantitative nutrient assessment of agricultural residues from different crop types in Chungcheongnam-do, Korea

Effective management of crop residues is essential for sustainable agriculture.This study assessed the quantity and nutrient composition of by-products from greenhouse, upland, and orchard crops in the Chungcheongnam-do region of South Korea based on a survey of 501 farms.Orchard by-products had the highest recycling rate (69.2%), followed by upland (48.6%) and greenhouse crops (44.2%).Residues of watermelon, cucumber, cabbage, and sweet potato had low C/N ratios, while upland and orchard residues with high lignin content showed relatively high C/N ratios, highlighting the need for utilization strategies based on crop-specific C/N characteristics.Leguminous crops such as soybean and sesame contained the highest nutrient concentrations per unit area, suggesting potential as substitutes for organic fertilizers.These findings provide crop-specific data to guide optimized recycling strategies and promote localized circular resource systems.