农业环境科学学报2018，Vol.37Issue(5)：1035-1044,10.DOI:10.11654/jaes.2017-1179
"双季稻-冬闲田"生态系统碳交换动态变化及其影响因素
Seasonal variation in carbon exchange and its modulating factors of a double cropping rice ecosystem in Southern China
摘要
Abstract
In this study,the CO2flux of a typical double cropping rice ecosystem was continuously monitored by the eddy covariance tech-nique. The carbon exchange [Net ecosystem exchange(NEE), Gross primary productivity(GPP)and Ecosystem respiration(Reco)] in the double cropping rice ecosystem and its regulatory factors were analyzed. The results showed that the NEE of the double cropping rice e-cosystem had clear diurnal and seasonal variations. The daily diurnal variation in NEE showed a significant U-shaped curve during the growing season,and the peak values were different for each month.The seasonal variation in NEE showed two uptake periods(when NEE was negative)and three emission periods(when NEE was positive). The NEE results showed two significant carbon uptake periods in the growing season of the early rice stage and the late rice stage.The average daily value for NEE in early rice was-0.58 g C·m-2,and the maximum appeared on June 20(-1.77 g C·m-2).The average value for NEE in late rice was-1.28 g C·m-2and the maximum appeared on September 19(-2.23 g C·m-2).There were two carbon emission periods during the non-crop growing period in winter,where the mean value was 2.68 g C·m-2.The daytime NEE during rice cultivation was significantly affected by photosynthetically active radiation.The night-time NEE was significantly affected by the soil temperature at 5 cm depth, and the temperature sensitivity at the winter fallow stage was higher than in the double cropping season when the temperature was higher. The total NEE for the whole year indicated that the double cropping rice ecosystem created carbon emissions that reached 778.4 g C·m-2,while GPP was 1 643.7 g C·m-2,and Recowas 2 425.8 g C·m-2. Therefore,the southern double-cropping rice ecosystem has a very significant potential for carbon sequestration and emission mitigation.关键词
涡度相关/碳交换/双季稻生态系统Key words
eddy covariance/carbon exchange/double cropping rice ecosystem分类
农业科技引用本文复制引用
魏甲彬,徐华勤,周玲红,成小琳,唐先亮,傅志强,唐启源,唐剑武.."双季稻-冬闲田"生态系统碳交换动态变化及其影响因素[J].农业环境科学学报,2018,37(5):1035-1044,10.基金项目
国家自然科学基金项目(41571293) （41571293）
湖南省科技厅区域合作项目(2016WK2009) （2016WK2009）
国家水稻产业体系项目(CARS-01-30).The National Natural Science Foundation of China(41571293) （CARS-01-30）
The Regional Cooperation Project of Hunan Provincial Department of Science and Technology(2016WK2009) （2016WK2009）
The National Rice Industry System of China(CARS-01-30) （CARS-01-30）
