Precipitation increase counteracts warming effects on plant and soil C:N:P stoichiometry in an alpine meadow

作者：Lina Shi, Zhenrong Lin, Xiaoting Wei, Cuoji Peng, Zeying Yao, Bing Han, Qing Xiao, Huakun Zhou, Yanfang Deng, Kesi Liu, Xinqing Shao · 发表于：Frontiers in Plant Science · 年份：2022 · DOI：10.3389/fpls.2022.1044173 · 被引用次数：40 · 研究领域：Soil Carbon and Nitrogen Dynamics、Pasture and Agricultural Systems、Peatlands and Wetlands Ecology

Temperature and precipitation are expected to increase in the forthcoming decades in the northeastern Qinghai-Tibetan Plateau, with uncertain effects of their interaction on plant and soil carbon:nitrogen:phosphorus (C:N:P) stoichiometry in alpine ecosystems. A two-year field experiment was conducted to examine the effects of warming, precipitation increase, and their interaction on soil and plant C:N:P stoichiometry at functional groups and community level in an alpine meadow. Warming increased aboveground biomass of legumes and N:P ratios of grasses and community, but did not affect soil C:N:P stoichiometry. The piecewise structural equation model (SEM) indicated that the positive effect of warming on community N:P ratio was mainly resulted from its positive influence on the aboveground biomass of functional groups. Precipitation increase reduced C:N ratios of soil, grasses, and community, indicating the alleviation in soil N-limitation and the reduction in N use efficiency of plant. SEM also demonstrated the decisive role of grasses C:N:P stoichiometry on the response of community C:N:P stoichiometry to precipitation increase. The interaction of warming and precipitation increase did not alter plant community and soil, N:P and C:P ratios, which was resulting from their antagonistic effects. The stable soil and plant community C:N:P stoichiometry raised important implications that the effect of warming was offset by precipitation increase. Our study highlights the importanc...