CASCADING EFFECTS OF LITTER-SOIL NUTRIENT STOICHIOMETRY ON ENZYME ACTIVITIES DURING KARST FOREST SUCCESSION IN SOUTHWEST CHINA

Litter serves as a source of enzymes and substrates, with enzymatic transformations regulating soil nutrient cycling.These three components (litter, enzymes, and soil nutrient) interact synergistically to maintain soil ecological functions and material balance.Currently, a significant knowledge gap exists regarding the cascade effects linking litter decomposition, soil enzyme activity, and soil nutrients during mid-succession in karst forests.The results indicated that: (1) Variations in plant species composition across different successional stages led to significant differences in litter stoichiometry.(2) Changes in litter stoichiometry significantly influenced alterations in soil nutrients and enzyme activity.(3) Soil nutrient factors (SOC, TN, HN, TP, AP, C/N, C/P, N/P) significantly drove changes in soil enzyme activity, with SOC being the most important driving factor.In summary, karst forest succession influences the cascade relationships among litter, soil nutrients, and soil enzyme activity.