Responses of Soil Organic Carbon Decomposition and Temperature Sensitivity to N and P Fertilization in Different Soil Aggregates in a Subtropical Forest

作     者：Li, Jing Liu, Shengen Zhao, Xuechao Wang, Qingkui 

作者机构：Chinese Acad Sci Key Lab Forest Ecol & Management Huitong Expt Stn Forest Ecol Inst Appl Ecol Shenyang 110164 Peoples R China Univ Chinese Acad Sci Beijing 101407 Peoples R China China Three Gorges Univ Coll Biol & Pharmaceut Sci Yichang 443000 Peoples R China Anhui Agr Univ Sch Forestry & Landscape Architecture Hefei 230031 Peoples R China 

出 版 物：《FORESTS》 (森林)

年 卷 期：2023年第14卷第1期

页      面：72页

核心收录：

学科分类：0907[农学-林学] 08[工学] 0829[工学-林业工程] 09[农学] 

基　　金：National Natural Science Foundation of China [31830015  32171752] 

主　　题：soil organic carbon decomposition temperature sensitivity fertilization soil aggregate forest ecosystem 

摘      要：Soil organic carbon (SOC) decomposition, a key process controlling the carbon (C) loss from terrestrial soils to the atmosphere, varies with soil aggregate size and is influenced by increasing nitrogen (N) and phosphorus (P) inputs from anthropogenic activities. However, how increasing N and P affects SOC decomposition and its temperature sensitivity (Q(10)) in soil aggregates remains unclear. Thus, we collected soils from a subtropical Cunninghamia lanceolata forest receiving N and P addition for 8 years to explore the interactive effects of N and P fertilization on SOC decomposition and its Q(10) in mega-aggregates (2 mm, MeA), macroaggregates (0.25-2.0 mm, MaA), and microaggregates (0.25 mm, MiA). Results showed that aggregate size has a huge influence on SOC decomposition and its Q(10). Specifically, SOC decomposition in MiA is 49.2% and 26.0% higher than MeA and MaA, respectively. Moreover, the averaged Q(10) values were 2.29, 2.26 and 1.83 in MeA, MaA and MiA. SOC decomposition significantly increased by 39.4% in MaA and 23.7% in MiA with N fertilization, but P fertilization had less impact. However, P fertilization increased Q(10) by 46.7% in MeA and 46.6% in MaA. Furthermore, we found P fertilization changed the influences of N fertilization on SOC decomposition in MaA and MiA but had no effect on responses of Q(10) to N fertilization. Overall, our findings suggested that there were differences in SOC decomposition and Q(10) among aggregates, and fertilization treatment had an impact on them. Our results highlighted the significance of considering differences in SOC decomposition and its response to climate warming and nutrient input among different aggregates in the prediction of SOC dynamics and its feedback to environmental changes in terrestrial ecosystems under climate warming scenarios.