Eighteen‐year nitrogen addition does not increase plant phosphorus demand in a nitrogen‐saturated tropical forest

作者：Guangcan Yu, Jing Chen, Mengxiao Yu, Andi Li, Ying‐Ping Wang, Xinhua He, Xuli Tang, Hui Liu, Jun Jiang, Jiangming Mo, Shuo Zhang, Junhua Yan, Mianhai Zheng · 发表于：Journal of Ecology · 年份：2023 · DOI：10.1111/1365-2745.14118 · 被引用次数：33 · 研究领域：Soil Carbon and Nitrogen Dynamics、Soil and Water Nutrient Dynamics、Plant nutrient uptake and metabolism

Abstract Nitrogen (N) deposition usually increases plant tissue N concentrations and thus phosphorus (P) demand in young and/or N‐limited forests, but the N deposition effect on plant P demand has rarely been assessed in N‐saturated forests. Impacts of 18‐year external N additions (Control: 0, Low N: 50, Moderate N:100 and High N: 150 kg N ha −1 year −1 ) on leaf P of four plant life‐forms (tree, shrub, herb and liana), P fractions of bulk and rhizosphere soils were examined in a N‐saturated mature tropical forest in southern China. Leaf N, P and N: P ratios of all plant life‐forms remained stable under three N additions. Among soil P fractions, moderate labile organic P increased by 25%–33% across three N additions; and soil total P was increased by 11.76% under Low N, and 8.87% under High N, compared with the control. The PLS‐PM results showed that path coefficient of microbial community to available P significantly increased and of inorganic P to available P significantly decreased under N additions than control. N additions improved soil P availability through microbe‐mediated P transformation: Low N significantly increased soil microbial taxonomic diversity, and a higher microbial diversity could enlarge the sources of nutrient acquisition and stimulate decomposition of recalcitrant organic matters; while High N significantly decreased soil microbial taxonomic diversity, the remaining microorganisms that were screened by N‐rich environments had the characteristics of res...