Stage-dependent associations between leaf litter chemistry and decomposition under nitrogen deposition and reduced precipitation in a subtropical forest

作者：Shixing Zhou, Xingcheng Zou, Renping Wan, Zepeng Liang, Lin Xiao, Kaiwen Pan, Junxi Hu, Congde Huang · 发表于：Frontiers in Forests and Global Change · 年份：2026 · DOI：10.3389/ffgc.2026.1923667 · 研究领域：Soil Carbon and Nitrogen Dynamics、Ecology and Vegetation Dynamics Studies、Forest Ecology and Biodiversity Studies

Litter decomposition regulates carbon sequestration and nutrient cycling in forest ecosystems and is sensitive to nitrogen deposition and drought. As decomposition proceeds, litter chemistry changes and the decomposition rate decrease, likely with a change in rate-regulating factors. However, the effects of nitrogen deposition and reduced precipitation on litter decomposition over time and the stage-dependent associations between leaf litter chemistry and decomposition remain poorly understood. Here, we conducted a 2-year in situ manipulation experiment in a subtropical evergreen broad-leaved forest to examine how simulated nitrogen deposition (150 kg N ha −1 yr. −1 ) and 10% throughfall reduction altered temporal patterns of litter chemistry and decomposition dynamics. Both nitrogen deposition and reduced precipitation significantly inhibited leaf litter decomposition in the early and late decomposition stages. The litter chemistry parameters that explained variation in cumulative mass loss differed among treatments. However, litter phosphorus, manganese and iron concentrations, together with the carbon-to-phosphorus ratio, were among the best predictors of cumulative mass loss across treatments in the early decomposition stage, whereas manganese concentration was the best predictor in the late stage. These results indicate that nitrogen deposition and reduced precipitation inhibited leaf litter decomposition throughout the study period. Often overlooked litter chemical trai...