文献类型：期刊文献

英文题名：Effects of simulated nitrogen deposition on soil respiration: Evidence from a three-year field study of the Abies georgei (Orr) forest in the Jiaozi Snow Mountains National Nature Reserve, Southwest China

作者：Yuan, Jiyou[1] Peng, Mingchun[1] Tang, Guoyong[2] Wang, Yun[3]

第一作者：Yuan, Jiyou

机构：[1] School of Ecology and Environmental Sciences & Yunnan Key Laboratory for Plateau Mountain Ecology and Restoration of Degraded Environments, Yunnan University, Yunnan, Kunming, 650091, China; [2] Institute of Highland Forest Science, Chinese Academy of Forestry, Kunming, 650233, China; [3] Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection, College of Resources and Environment, Linyi University, Linyi, 276000, China

年份：2023

卷号：542

外文期刊名：Forest Ecology and Management

收录：EI(收录号：20232114141172);Scopus(收录号：2-s2.0-85159783228)

语种：英文

外文关键词：Carbon - Climate change - Forestry - Nitrates - Nitrogen - Sodium nitrate - Soils - Tropics

摘要：The impact of increased deposition of atmospheric nitrogen on forest soil respiration is one of the focal issues amid global climatic changes. However, the impact of increased atmospheric nitrogen deposition on soil respiration (Rs) in the subtropical Abies georgei (Orr) Forest remains unknown. Hence, a 3-year field experiment was conducted in the subtropical Abies georgei (Orr) Forest from 2019 to 2021 to quantify the impact of three forms of nitrogen source ((NH4)2SO4 NaNO3 NH4NO3) at four rates (0, 5, 15, and 30 kg N.ha?1.yr?1) on Rs. We found that at the early stage of nitrogen application (1–9 months), nitrogen addition increased microbial respiration (Rm) and root respiration (Rt) by 10.12% and 8.14% on average, respectively. The increase in Rm and Rt induced by nitrogen deposition resulted in an increase of 18.16% in Rs. At the later stage of the study (18–36 months), nitrogen application resulted in a significant reduction of 17.39% in Rm and an 18.17% reduction in Rs. However, no significant effect on Rt was observed during the later stages of nitrogen deposition. The annual emission flux of Rs increased by 7.23% in the first year, remained unchanged in the second year, and decreased by 4.43% in the third year. Moreover, the results showed that biological (i.e., soil microorganisms and plant roots) and abiotic (i.e., soil temperature and moisture) factors jointly controlled Rs. A structural equation model showed that soil temperature, soil microbial biomass carbon, and nitrogen were the key controlling factors for Rs, Rm and Rt, respectively. Therefore, these findings suggest that interactions between these drivers, as well as the contributions of Rm and Rt are necessary for the assessment of the impact of nitrogen deposition on Rs and soil carbon processes in the context of global climate change. ? 2023