作者机构：
[郭俊丽; 葛体达; 魏文学; 刘毅] Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha;410125, China;[王光军] College of Life Science and Engineering, Central South University of Forestry and Technology, Changsha;410004, China;[田美洁] College of Agronomy, Hunan Agricultural University, Changsha
通讯机构：
Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
作者机构：
[郭俊丽; 王光军] College of Life Science and Technology, Central South University of Forestry and Technology, Changsha;410004, China;[刘毅; 魏文学; 葛体达] Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha;410125, China;[郭俊丽] 410004, China<&wdkj&>Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha
通讯机构：
College of Life Science and Technology, Central South University of Forestry and Technology, Changsha, China
作者机构：
中南林业科技大学生命科学与技术学院, 长沙, 410004;湖南会同杉木林国家重点野外科学观测研究站, 湖南会同杉木林国家重点野外科学观测研究站, 湖南, 会同, 418307;南方林业生态应用技术国家工程实验室, 南方林业生态应用技术国家工程实验室, 长沙, 410004;[赵梅芳] Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, 410004, China, Huitong National Field Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystem in Hunan Province, Huitong,, Hunan 418307, China;[闫文德; 王光军; 玉昉永; 彭曦; 王凤琪] Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, 410004, China, Huitong National Field Station for Scientific Observation and Research of Chinese Fir Plantation Ecosystem in Hunan Province, Huitong,, Hunan 418307, China, National Engineering Laboratory for Applied Forest Ecological Technology in Southern China, Changsha, 410004, China
通讯机构：
[Zhao, M.-F.] F;Faculty of Life Science and Technology, Central South University of Forestry and Technology, Changsha, China
作者机构：
[唐美玲; 王光军] College of Life Science and Engineering, Central South University of Forestry and Technology, Changsha;410004, China;[肖谋良; Yuan, Hong-Zhao; 刘守龙; 祝贞科; 葛体达; 吴金水] Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha;410125, China;[唐美玲] 410004, China<&wdkj&>Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha
摘要：
This study provides a complete account of global warming potential (GWP) and greenhouse gas intensity (GHGI) in relation to a long-term water management experiment in Chinese double-rice cropping systems. The three strategies of water management comprised continuous (year-round) flooding (CF), flooding during the rice season but with drainage during the midseason and harvest time (F-D-F), and irrigation only for flooding during transplanting and the tillering stage (F-RF). The CH4 and N2O fluxes were measured with the static chamber method. Soil organic carbon (SOC) sequestration rates were estimated based on the changes in the carbon stocks during 1998-2014. Longer periods of soil flooding led to increased CH4 emissions, reduced N2O emissions, and enhanced SOC sequestration. The net GWPs were 22,497, 8,895, and 1,646 kg CO2-equivalent ha(-1) yr(-1) for the CF, F-D-F, and F-RF, respectively. The annual rice grain yields were comparable between the F-D-F and CF, but were reduced significantly (by 13%) in the F-RF. The GHGIs were 2.07, 0.87, and 0.18 kg CO2-equivalent kg(-1) grain yr(-1) for the CF, F-D-F, and F-RF, respectively. These results suggest that F-D-F could be used to maintain the grain yields and simultaneously mitigate the climatic impact of double rice-cropping systems.
摘要：
Climate change is expected to cause the alteration of litter production in forests, which may result in substantial changes in soil CO2 efflux (FCO2) process as litter represents a major pathway of carbon from vegetation to the soils. In this study, we conducted an aboveground litter manipulation experiment to examine the influence of litter addition and exclusion on soil FCO2 in Camphor tree, Masson pine, and mixed Camphor tree and Masson pine forests in central south China. Litter input manipulation included three treatments: non-litter input (litter exclusion), double litter input (litter addition), and natural litter input (control). On average, litter exclusion significantly reduced soil FCO2 rate by approximately 39%, 24% and 22% in Camphor tree forests, the Mixed forests, and Masson pine forests, respectively. On a yearly basis, double litter addition significantly increased soil CO2 by 12% in the Mixed forests (P=0.02) but not in both Camphor tree and Masson pine forests (P>0.05), when compared with their corresponding control treatments. However, litter addition increased soil FCO2 rates in the months of June-August in Camphor tree and Masson pine forests, coinciding with high soil temperature of summer conditions. Litter exclusion reduced soil FCO2 more than litter addition increased it in the study sites. Responses of soil respiration to litter input treatments varied with forest types. Litter input treatments did not alter the seasonal patterns of soil temperature and soil water content. Our results indicated that changes in aboveground litter as a result of global climate change and/or forest management have a great potential to alter soil respiration and soil carbon balance in forest ecosystems.
