Article Effects of One-Year Simulated Nitrogen and Acid Deposition on Soil Respiration in a Subtropical Plantation in China Shengsheng Xiao 1,2,*, G. Geoff Wang 3, Chongjun Tang 1,2, Huanying Fang 2, Jian Duan 1,2 and Xiaofang Yu 4 1 Jiangxi Provincial Key Laboratory of Soil Erosion and Prevention, Nanchang 330029, China;
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[email protected] (J.D.) 2 Jiangxi Institute of Soil and Water Conservation, Nanchang 330029, China;
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[email protected] Received: 18 December 2019; Accepted: 14 February 2020; Published: 20 February 2020 Abstract: Atmospheric nitrogen (N) and acid deposition have become global environmental issues and are likely to alter soil respiration (Rs); the largest CO2 source is from soil to the atmosphere. However, to date, much less attention has been focused on the interactive effects and underlying mechanisms of N and acid deposition on Rs, especially for ecosystems that are simultaneously subjected to elevated levels of deposition of both N and acid. Here, to examine the effects of N addition, acid addition, and their interactions with Rs, we conducted a two-way factorial N addition 1 1 1 1 (control, CK; 60 kg N ha− a− , LN; 120 kg N ha− a− , HN) and acid addition (control, CK; pH 4.5, LA; pH 2.5, HA) field experiment in a subtropical plantation in China.