Abstract:

Understanding the release pattern of potassium during the decomposition of Camellia sinensis pruning and its relationship with enzyme activity is important for understanding plant growth and ecosystem nutrient cycling.An in-situ decomposition experiment was conducted using the litterbag method in the Jiuan ecological tea garden in Huaxi District,Guiyang,Guizhou Province from 2022 to 2024.Samples were collected at 10 time points(2,4,6,8,10,12,15,18,21,and 24 months)to measure the dry mass loss rate,potassium retention rate,potassium release rate,and six enzymes.One-way ANOVA was used to compare differences in these indicators across decomposition stages,while Pearson correlation and stepwise regression analyses were applied to examine the relationship between potassium release rate and enzyme activities.The results indicate that:1)The potassium release from Camellia sinensis prunings exhibits a typical biphasic("fast-stable")pattern,characterized by a rapid release phase during the first four months,followed by a period of gradual stabilization.2)Correlation analysis shows that potassium release rate is significantly positively correlated with sucrase and acid phosphatase activities but significantly negatively correlated with catalase activity.3)Stepwise regression further indicates that sucrase,acid phosphatase,and catalase are key predictors of potassium release,with the model demonstrating a goodness-of-fit(R²=0.926).The prediction model based on enzyme activities can effectively explain the variation in the potassium release rate,providing theoretical support for precise potassium fertilizer management and the resourceful utilization of prunings.

Key words: Camellia sinensis prunings, potassium release, enzyme activity, decomposition dynamics, predictive model