Autor: |
Ai L; School of Geographical Sciences and Carbon Neutrality Future Technology, Fujian Normal University, Fuzhou 350117, China., Wu FZ; School of Geographical Sciences and Carbon Neutrality Future Technology, Fujian Normal University, Fuzhou 350117, China.; Key Laboratory of Humid Subtropical Eco-geographical Process of Ministry of Education, Fujian Normal University, Fuzhou 350117, China.; Sanming Forest Ecosystem National Observation and Research Station, Sanming 365002, Fujian, China., Fan XB; School of Geographical Sciences and Carbon Neutrality Future Technology, Fujian Normal University, Fuzhou 350117, China., Yang J; School of Geographical Sciences and Carbon Neutrality Future Technology, Fujian Normal University, Fuzhou 350117, China., Wu QX; School of Geographical Sciences and Carbon Neutrality Future Technology, Fujian Normal University, Fuzhou 350117, China., Zhu JJ; School of Geographical Sciences and Carbon Neutrality Future Technology, Fujian Normal University, Fuzhou 350117, China., Ni XY; School of Geographical Sciences and Carbon Neutrality Future Technology, Fujian Normal University, Fuzhou 350117, China.; Key Laboratory of Humid Subtropical Eco-geographical Process of Ministry of Education, Fujian Normal University, Fuzhou 350117, China.; Sanming Forest Ecosystem National Observation and Research Station, Sanming 365002, Fujian, China. |
Abstrakt: |
Litter input triggers the secretion of soil extracellular enzymes and facilitates the release of carbon (C), nitrogen (N), and phosphorus (P) from decomposing litter. However, how soil extracellular enzyme activities were controlled by litter input with various substrates is not fully understood. We examined the activities and stoichiometry of five enzymes including β-1,4-glucosidase, β-D-cellobiosidase, β-1,4- N -acetyl-glucosaminidase, leucine aminopeptidase and acidic phosphatase (AP) with and without litter input in 10-year-old Castanopsis carlesii and Cunninghamia lanceolata plantations monthly during April to August, in October, and in December 2021 by using an in situ microcosm experiment. The results showed that: 1) There was no significant effect of short-term litter input on soil enzyme activity, stoichiometry, and vector properties in C. carlesii plantation. In contrast, short-term litter input significantly increased the AP activity by 1.7% in May and decreased the enzymatic C/N ratio by 3.8% in August, and decreased enzymatic C/P and N/P ratios by 11.7% and 10.3%, respectively, in October in C. lanceolata plantation. Meanwhile, litter input increased the soil enzymatic vector angle to 53.8° in October in C. lanceolata plantations, suggesting a significant P limitation for soil microorganisms. 2) Results from partial least squares regression analyses showed that soil dissolved organic matter and microbial biomass C and N were the primary factors in explaining the responses of soil enzymatic activity to short-term litter input in both plantations. Overall, input of low-quality (high C/N) litter stimulates the secretion of soil extracellular enzymes and accelerates litter decomposition. There is a P limitation for soil microorganisms in the study area. |