Long-term nitrogen addition has a positive legacy effect on soil respiration in subtropical Moso bamboo forests

作者：Quan Li, Chao Zhang, Man Shi, Jianhua Lv, Changhui Peng, Junbo Zhang, Scott X. Chang, Tingting Cao, Tong Li, Xinzhang Song · 发表于：Geoderma · 年份：2024 · DOI：10.1016/j.geoderma.2024.117092 · 被引用次数：5 · 研究领域：Soil Management and Crop Yield、Bamboo properties and applications、Soil Carbon and Nitrogen Dynamics

• Soil respiration exhibits clear temporal dynamics in the context of long-term N input. • N input legacy increased autotrophic respiration but reduced heterotrophic respiration. • Microbial traits and fine root biomass played a key role in changing soil respiration. Soil respiration (Rs), a critical component of the global carbon (C) cycle, is sensitive to changes in nitrogen (N) deposition. However, the temporal dynamics of the effects of long-term (≥ five years) N addition and its cessation on Rs in forests remain uncertain. We conducted a continuous field experiment, which included three years of N cessation after seven years of N addition at different rates (0, 30, 60, and 90 kg N∙ha −1 ∙yr −1 ), in a subtropical Moso bamboo forest to explore the response of Rs and its components, determine the influence of biotic and abiotic factors to long-term N addition, and identify any legacy effects. We found a two-phase pattern of Rs, with a significant increase in the first two years across three N addition rates and a constant significant increase in the last five years across low and medium N addition; however, Rs did not change under high N addition. The nitrogen addition legacy effects significantly increased Rs and autotrophic respiration but reduced heterotrophic respiration, which could persist for at least three years. The mechanism underlying the temporal variation in Rs and its components was related to the increase in fine root biomass and changes in soil microbial bi...