生态学报2026，Vol.46Issue(8)：4350-4359,10.DOI:10.20103/j.stxb.202505271322
模拟减雨处理和细根移除对半湿润区刺槐林凋落叶分解的影响
Effects of rainfall reduction and fine root exclusion on leaf litter decomposition in a Robinia pseudoacacia plantation in sub-humid region
摘要
Abstract
Litter decomposition,a key process in material cycling of vegetation ecosystems,is regulated by both litter characteristics and biotic/abiotic environmental factors.Investigation of these mechanisms is crucial for understanding ecosystem functions.This study conducted a 1-year in situ litterbag decomposition experiment in a Robinia pseudoacacia plantation in sub-humid region of Loess Plateau,comparing plots with natural precipitation(control)and 30%precipitation reduction(treated for 4 years),and subplots with and without fine roots exclusion.The results showed that rainfall exclusion significantly decreased decomposition rate of leaf litter,while the effect of fine root exclusion was not significant.After one growing season,mass loss rate of the leaf litter(39.3%)and decomposition coefficient(0.67)in treatment plot with fine roots were significantly lower than those in control plot(43.6%and 0.78,respectively)(P＜0.05).The activity of five enzymes in the soil near decomposition bags showed seasonal variation,with higher levels in the early period(May—August)than in the later period(November).However,most sample groups showed lower enzyme activity in treatment plot than in control plot.Sucrase and catalase activities in treatment plot were significantly lower,while polyphenol oxidase activity was higher(P＜0.05).The effect of rainfall reduction on alkaline phosphatase activity was not significant.Fine root exclusion significantly decreased sucrase,alkaline phosphatase,and catalase activities,but increased polyphenol oxidase activity(P＜0.05).No significant correlation was observed between decomposition rate and soil enzyme activities and major soil nutrient indicators.This study clarified the important role of rainfall reduction and soil moisture conditions in litter decomposition,and supported the potential role of fine roots in litter decomposition.Both soil moisture and fine roots may regulate litter decomposition and nutrient cycling in forests by affecting root exudates and soil microbial activity.关键词
凋落叶分解/减雨处理/细根移除/土壤酶活性Key words
leaf litter decomposition/rainfall reduction/fine root exclusion/soil enzyme activity引用本文复制引用
刘美君,罗伶书,常乐,李国庆,杜盛..模拟减雨处理和细根移除对半湿润区刺槐林凋落叶分解的影响[J].生态学报,2026,46(8):4350-4359,10.基金项目
国家重点研发计划项目(2017YFC0504601) （2017YFC0504601）
