干旱区生态环境知识资源中心(Arid): 中国北方植被水分利用效率的时间变化特征及其影响因子

Arid

	中国北方植被水分利用效率的时间变化特征及其影响因子
其他题名	Temporal changes of vegetation water use efficiency and its influencing factors in Northern China
	冯朝阳; 王鹤松; 孙建新
来源期刊	植物生态学报
ISSN	1005-264X
出版年	2018
卷号	42 期号:4 页码:453-465
中文摘要	水分利用效率(WUE)既是衡量植被生长适应性的重要指标,也是连接生态系统水碳循环的纽带。认识不同类型植被WUE的时间变化特征及驱动机制有助于增进对生态系统水碳循环过程的理解。已有研究表明,在不同时间尺度下,WUE呈现不同的时间变化特征,但现有研究多是集中在单一的时间尺度下开展的,对不同植被类型在不同时间尺度下的动态变化及影响因子分析开展得较少。该研究选用中国北方地区9个定位观测台站的通量与气象数据,分析了WUE的日内变化和季节变化特征,并在0.5 h、1 d、8 d以及月尺度下,分别分析了气温(T_a)、相对湿度(RH)、饱和水汽压差(VPD)以及光合有效辐射(PAR)等非生物因子对WUE的影响。同时,该研究也分析了植被叶面积指数(LAI)和降水(P)对WUE的影响。研究发现:(1)WUE的日变化呈现不对称的"U"型特征,日出时的WUE普遍高于日落时。荒漠地区WUE的季节变化呈"U"型,而其他站点呈现单峰型。不同站点WUE的季节变化可以分为总初级生产力(GPP)主导型和蒸发散(ET)主导型,并随着时间尺度的扩大,GPP或ET的主导作用逐渐增强。(2)在较短的时间尺度(0.5 h、1 d)上,T_a、RH、VPD和PAR是影响WUE变化的主要因子,但随着时间尺度的扩大,T_a和RH成为影响WUE变化的主要因子,并且与WUE的相关关系受GPP或ET对WUE主导作用的影响,随着时间尺度增大,T_a和RH与WUE的线性关系更加显著。(3)WUE大体上随LAI的增加而增加,但当LAI超过一定值时,在长白山、海北和张掖站,WUE对LAI的敏感性降低。降水与WUE的关系在研究区域内并不显著。(4)不同植被类型的WUE由大到小依次为森林、农田、草地、湿地和荒漠。
英文摘要	Aims Water use efficiency(WUE)is an important variable for evaluating the growth adaptation of vegetation;it links carbon and water cycles of terrestrial ecosystems.Charactering the spatial and temporal variations in WUE and the driving factors not only can help understand the processes and regulations of ecosystem carbon and water cycles,but also provides scientific basis for formulating sustainable regional development policies and guiding water resources management.This study was conducted to determine the patterns of temporal changes for different vegetation types in northern China.Methods Flux and meteorological data of nine field observation sites in northern China were used to analyze the changes of WUE under different temporal scales,including half-hourly,daily,8-day intervals,and monthly.The effects of temperature(T_a),relative humidity(RH),vapor pressure deficit(VPD)and photosynthetically active radiation(PAR)on WUE under different time scales were also examined.Important findings(1)Diurnal change of WUE displayed an asymmetric "U" shape,with greater values at the sunrise than at the sunset.The seasonality of WUE in the Gobi and desert areas displayed a pattern of "U" shape,while it occurred as a single peak in other regions.The seasonal changes of WUE can be further divided into the types of gross primary production(GPP)-driven and the evapotranspiration(ET)-driven;the significance of either driven type increases with time.(2)T_a,RH,VPD and PAR were the main factors influencing the changes of WUE on a shorter temporal scale(half-hourly and daily).With increasing temporal scale,T_a and RH continue to remain the main factors affecting the changes of WUE,and their correlations with WUE were influenced by the prevailing role of GPP or ET.Moreover,the correlation coefficients became more significant with increasing temporal scales.(3)WUE increased with increases in leaf area index(LAI)until a certain value,beyond which the sensitivity of WUE to LAI decreased at the Changbai Mountain,Haibei and Zhangye stations.The relationship between precipitation and WUE was not significant in all the study areas.(4)Among the vegetation types,WUE ranked in order from high to low as forest,cropland,grassland,wetland and desert.
中文关键词	水分利用效率 ; 通量观测 ; 总初级生产力 ; 蒸发散 ; 气象因子
英文关键词	water use efficiency flux measurement gross primary production evapotranspiration meteorological factor
语种	中文
国家	中国
收录类别	CSCD
WOS类目	PLANT SCIENCES
WOS研究方向	Plant Sciences
CSCD记录号	CSCD:6268049
来源机构	北京林业大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/238629
作者单位	北京林业大学林学院, 北京 100083, 中国
推荐引用方式 GB/T 7714	冯朝阳,王鹤松,孙建新. 中国北方植被水分利用效率的时间变化特征及其影响因子[J]. 北京林业大学,2018,42(4):453-465.
APA	冯朝阳,王鹤松,&孙建新.(2018).中国北方植被水分利用效率的时间变化特征及其影响因子.植物生态学报,42(4),453-465.
MLA	冯朝阳,et al."中国北方植被水分利用效率的时间变化特征及其影响因子".植物生态学报 42.4(2018):453-465.