QQ客服 官方微博 反馈留言

	Environmental effects on net ecosystem co(2) exchange at half-hour and month scales over stipa krylovii steppe in northern china
	Wang, Yunlong1,2; Zhou, Guangsheng1,3; Wang, Yuhui1
刊名	Agricultural and forest meteorology
	2008-05-15
卷号	148期号:5页码:714-722
关键词	Net ecosystem carbon dioxide exchange Environmental effects Eddy covariance Stipa krylovii steppe
ISSN号	0168-1923
DOI	10.1016/j.agrformet.2008.01.013
通讯作者	Zhou, guangsheng(gszhou@ibcas.ac.cn)
英文摘要	The objectives of this research are to quantify the magnitude of co(2) exchange and to investigate the responses of net ecosystem co(2) exchange (nee), gross ecosystem production (gep) and ecosystem respiration (r(e)) to environmental factors over a temperate stipa krylovii steppe by an eddy covariance system in northern china. differences in annual precipitation, soil water content (swc), air temperature (t(a)) and evapotranspiration (et) were the most important factors which controlled patterns and variations of co(2) exchange between atmosphere and the steppe. precipitation received at study site was 297 mm in 2004, close to the average value during 1971-2000 (+/- s.d., 290 +/- 82 mm), whereas precipitations in 2005 (174 mm) and 2006 (215 mm) were significantly below the average. the lowest values of precipitation and swc in 2005 resulted in much lower carbon exchange rate related to those in 2004 and 2006. in 2005, daytime nee reached the seasonal peak about -3 mu mol c m(-2) s(-1), this was much lower than those in 2004 and 2006 (-7 to -8 mu mol c m(-2) s(-1)). seasonal peaks of integrated monthly nee was the lowest in 2005 (-8.8 g c m(-2) mon(-1)) and the highest in 2004 (-34.3 g c m(-2) mon(-1)). compared with 2004, the peak values of monthly gep and r(e) in 2005 reduced more than 30% and 20% due to soil water stress. swc was an important environmental factor regulated the variation of co(2) exchange. at ;hour time scale, daytime nee was positive when swc was less than 0.15 m(3) m(-3), r(e) tripled when swc increased from 0.075 to 0.225 m(3) m(-3). at month time scale, swc was the primary factor controlling monthly co(2) fluxes, there was no net carbon uptake until swc exceeded 18%, in the low (lai < 0.5 m(2) m(-2)) and the high (lai > 0.5 m(2) m(-2)) ranges of lai, swc explained about 71% and 90% variations in monthly nee, and about 92% and 82% variations in monthly gep. except swc, nee-light response curve was also regulated by air temperature because it influenced both plant photosynthetic capacity and the variations of soil and plant respirations. the optimal air temperature for the carbon uptake of s. krylovii steppe was 10-20 degrees c, carbon uptake decreased in magnitude when air temperature departed from this range. the close relationship between et and co(2) fluxes was explained that et was determined by both swc and t(a). at monthly scale, et predicted 62% variations of nee, 78% variations of gep, 85% variations of r(e). accumulative et and accumulative nee in growing seasons were tightly coupled. the highest et coincided with carbon sink in the growing season of 2006, and the lowest et in 2005 resulted in the maximum carbon loss. (c) 2008 elsevier b.v. all rights reserved.
WOS关键词	CARBON-DIOXIDE EXCHANGE ; NATIVE TALLGRASS PRAIRIE ; LEYMUS-CHINENSIS STEPPE ; WATER-VAPOR EXCHANGE ; INNER-MONGOLIA ; PRIMARY PRODUCTIVITY ; SEASONAL-VARIATION ; TUSSOCK GRASSLAND ; SOIL RESPIRATION ; SUMMER DROUGHT
WOS研究方向	Agriculture ; Forestry ; Meteorology & Atmospheric Sciences
WOS类目	Agronomy ; Forestry ; Meteorology & Atmospheric Sciences
语种	英语
出版者	ELSEVIER SCIENCE BV
WOS记录号	WOS:000256691700003
内容类型	期刊论文
URI标识	http://www.corc.org.cn/handle/1471x/2385141
专题	中国科学院大学
通讯作者	Zhou, Guangsheng
作者单位	1.Chinese Acad Sci, Inst Bot, State Key Lab Vegetat & Environm Change, Beijing 100093, Peoples R China 2.Chinese Acad Sci, Grad Sch, Beijing 100039, Peoples R China 3.China Meteorol Adm, Inst Atmospher Environm, Shenyang 110016, Peoples R China
推荐引用方式 GB/T 7714	Wang, Yunlong,Zhou, Guangsheng,Wang, Yuhui. Environmental effects on net ecosystem co(2) exchange at half-hour and month scales over stipa krylovii steppe in northern china[J]. Agricultural and forest meteorology,2008,148(5):714-722.
APA	Wang, Yunlong,Zhou, Guangsheng,&Wang, Yuhui.(2008).Environmental effects on net ecosystem co(2) exchange at half-hour and month scales over stipa krylovii steppe in northern china.Agricultural and forest meteorology,148(5),714-722.
MLA	Wang, Yunlong,et al."Environmental effects on net ecosystem co(2) exchange at half-hour and month scales over stipa krylovii steppe in northern china".Agricultural and forest meteorology 148.5(2008):714-722.

个性服务

查看访问统计

相关权益政策

暂无数据

收藏/分享

除非特别说明，本系统中所有内容都受版权保护，并保留所有权利。