Field Experiments and a Meta‐Analysis Reveal a Minor Influence of Nitrogen Addition on Phosphorus Fractions in Forests
Qingshui Yu, Xiaofeng Ni, Frank Hagedorn, Josep Peñuelas, Jordi Sardans, Mai–He Li, Suhui Ma, Jianxiao Zhu, Di Tian, Chengyang Zheng, Jiangling Zhu, Chengjun Ji, Zhiyao Tang, Jingyun Fang
Abstract
Anthropogenic nitrogen (N) inputs can significantly impact nutrient cycling and ecosystem functioning in terrestrial ecosystems. However, the effects of N addition on phosphorus (P) cycling processes in forest ecosystems remain unclear. In this study, we combined data from a long-term (11-year) N addition experiment across seven different forests ranging from temperate to tropical biomes, with a global meta-analysis from 88 relevant publications, to investigate the responses of P cycling-related variables to N inputs in forest ecosystems. We found that N addition had little effect on most P cycling-related variables (e.g., leaf P, soil total P, soil available P, soil P fractions, and microbial biomass P) across the studied forest ecosystems. The meta-analysis highlighted that N-induced changes in P cycling were highly variable. Only a few variables, such as the leaf P concentration and the activity of soil acid phosphatase, presented significant responses to N addition and changed with climatic zone and the amount and duration of N inputs. Our study suggests that P cycling processes in forest ecosystems remain largely unaffected by N inputs. Our findings contribute to a better understanding and prediction of biogeochemical cycles in the context of N deposition related to anthropogenic activities and global climate change.