Nitrogen deposition mitigates long-term phosphorus input-induced stimulative effects on soil respiration in a tropical forest

作者：Xingyun Huang, Yingwen Li, Shiqin Yu, Yongxing Cui, Fangyuan Guan, Yongxing Li, Jingtao Wu, Yang Hu, Zhian Li, Ping Zhuang, Bi Zou, Guoming Qin, Jingfan Zhang, Jinge Zhou, Ruyi Ding, Faming Wang · 发表于：Geoderma · 年份：2024 · DOI：10.1016/j.geoderma.2024.117142 · 被引用次数：10 · 研究领域：Soil Carbon and Nitrogen Dynamics、Plant nutrient uptake and metabolism、Plant Water Relations and Carbon Dynamics

• Long-term phosphorus input enhanced soil respiration (R S ) and heterotrophic respiration (R H ) • Nitrogen deposition mitigated the stimulative effect of phosphorus input on R S by reducing R H. • Long-term phosphorus input decreased autotrophic respiration (R A ) by reducing plant litter input. • Nitrogen deposition mitigated R H by decreasing plant litter, carbon quality, and fungi biomass. Atmospheric nitrogen (N) deposition and anthropogenic phosphorus (P) input simultaneously affect soil respiration (R S ), a crucial process that mediates soil carbon (C) cycling. However, the interaction of N deposition and anthropogenic P input on R S , as well as its components—autotrophic respiration (R A ) and heterotrophic respiration (R H )—remain largely unexplored. Herein, we conducted an 8-year field experiment with N and P additions in a tropical secondary forest, integrating the vegetation traits, soil physicochemical properties, organic C fractions, and microbial properties, to explore the effects of nutrient inputs and their interactions on R S , R A , and R H . Over eight years, along P input significantly increased R S by 19.2% and R H by 42.1%. These increases were partially mitigated (by 33.2% annually for R S and 58.3% annually for R H ) with the addition of N. In contrast, the co-addition of N and P enhanced R A compared to alone N or P addition, suggesting that N deposition mitigated the stimulative effect of P input on R S by reducing R H rather than R A . The str...