青海省三江源地区退化草地蒸散特征
Characterizing the evapotranspiration of a degraded grassland in the Sanjiangyuan Region of Qinghai province
查看参考文献32篇
文摘
|
了解三江源地区退化草地的蒸散状况有助于认识该地区退化生态系统水循环,对该地区的生态安全有着重要的意义。本研究利用涡度相关法观测青海省玛沁县小嵩草退化草地(34.35°N;100.50°E,海拔3 963m)的水热通量,对该地区2006-2008年全年的蒸散情况进行了特征分析。研究表明,2006-2008年三江源退化草地的蒸散值分别为452.24,474.24,459.57mm,降水量分别为460.7,496.1,480.1mm,其中有75%以上的降水分布在生长季,全年水平上蒸散量与降水量之比(ET/PPT)为95%以上,蒸散量与降水量基本持平。生长季日蒸散量1.8~1.9mm/d,而非生长季日蒸散量<0.6mm/d。蒸散日变化和年变化均为单峰型,每年6-7月蒸散量最大,为2.0~2.2mm/d;日蒸散峰值出现在正午左右,其最大值生长季为0.21mm/h,非生长季为0.10mm/h。退化草地蒸散的主要环境因子是净辐射,其次为饱和水汽压亏和空气温度。随着生长季的推进,潜热对这些因素的敏感性逐渐增大。与未退化的矮嵩草草甸相比,退化草地生长季蒸散量较小,而非生长季蒸散量较大,这一结果表明,高寒草地的植被盖度驱动草地生态系统的蒸散。 |
其他语种文摘
|
The evapotranspiration(ET) of degraded grassland in the Sanjiangyuan region was investigated to further elucidate the water cycle in this region.The eddy covariance technique was used to measure evapotranspiration and sensible heat flux continuously for 3 years in this degraded grassland in Qinghai province,China.The annual precipitations(PPT) were 460.7,496.1,and 480.1 mm for the three consecutive years.The annual ETs were 452.24,474.24,and 459.57 mm,varying in accord with the annual PPT.About 75% of the annual ET occurred during the growing season from DOY121 to 300.The ratio of ET to PPT was greater than 95% during the study period,indicating that there is some balance between ET and PPT and the average in the growing season for each of the three years were 1.86,1.92,1.81 mm/d,respectively.However,the averaged ET was lower than 0.6 mm/d during the non-growing season.The annual and daily dynamics were single peak type curves.The maximum monthly ET rate was 2.0-2.2 mm/d,which occurred mainly in June or July.The daily peak appeared at noon and was 0.21 and 0.10 mm/h during the growing and non-growing seasons respectively.ET was most sensitive to net radiation during the growing season while the effect of air temperature and vapour pressure deficit were secondary.Compared with the non-degraded area of Kobresia humilis meadow,the ET of the degraded grassland was lower in the growing season but higher in the non-growing season.The lower vegetation cover was attributed to this result. |
来源
|
草业学报
,2012,21(3):223-233 【核心库】
|
关键词
|
涡度相关法
;
蒸散
;
三江源地区
;
青海省
;
退化草地
|
地址
|
1.
中国科学院西北高原生物研究所, 青海, 西宁, 810008
2.
青海师范大学数学系, 青海, 西宁, 810001
|
语种
|
中文 |
文献类型
|
研究性论文 |
ISSN
|
1004-5759 |
学科
|
畜牧、动物医学、狩猎、蚕、蜂 |
基金
|
国家973计划
;
国家自然科学基金项目
;
青海省科技厅项目
|
文献收藏号
|
CSCD:4558775
|
参考文献 共
32
共2页
|
1.
Brutsaert W.
Evaporation into the Atmosphere: Theory, History, and Applications,1982
|
被引
8
次
|
|
|
|
2.
Wever L A. Seasonal and interannual variation in evapotranspiration, energy balance and surface conductance in a northern temperate grassland.
Agricultural and Forest Meteorology,2002,112(1):31-49
|
被引
48
次
|
|
|
|
3.
Adams J M. Increases in terrestrial carbon storage from the Last Glacial Maximum to the present.
Nature,1990,348:711-714
|
被引
72
次
|
|
|
|
4.
马致远. 三江源地区水资源的涵养和保护.
地球科学进展,2004,19(13):108-111
|
被引
8
次
|
|
|
|
5.
陈孝全.
三江源自然保护区生态环境,2002
|
被引
9
次
|
|
|
|
6.
王堃. 三江源地区草地资源现状及持续利用途径.
草地学报,2005(1):28-31
|
被引
38
次
|
|
|
|
7.
李博. 中国北方草地退化及其防治对策.
中国农业科学,1997,30(6):1-9
|
被引
252
次
|
|
|
|
8.
刘纪远. 近30年来青海三江源地区草地退化的时空特征.
地理学报,2008,63(4):364-376
|
被引
144
次
|
|
|
|
9.
王启基. 三江源区资源与生态环境现状及可持续发展.
兰州大学学报(自然科学版),2005,41(4):31-37
|
被引
7
次
|
|
|
|
10.
曹广民. 三江源区"黑土滩"型退化草地自然恢复的瓶颈及解决途径.
草地学报,2009(1):4-9
|
被引
52
次
|
|
|
|
11.
Baldocchi D D. Assessing the eddy covariance technique for evaluating carbon dioxide exchange rates of ecosystems: past, present and future.
Global Change Biology,2003,9(4):479-492
|
被引
153
次
|
|
|
|
12.
Li S G. Evapotranspiration from a Mongolian steppe under grazing and its environmental constraints.
Journal of Hydrology,2007,333(1):133-143
|
被引
17
次
|
|
|
|
13.
Bremer D J. Evapotranspiration in a prairie ecosystem: effects of grazing by cattle.
Agronomy Journal,2001,93(2):338-348
|
被引
8
次
|
|
|
|
14.
Meyers T P. A comparison of summertime water and CO_2 fluxes over rangeland for well watered and drought conditions.
Agricultural and Forest Meteorology,2001,106:205-214
|
被引
19
次
|
|
|
|
15.
Gu S. Characterizing evapotranspiration over a meadow ecosystem on the Qinghai-Tibetan Plateau.
Journal of Geophysical Research,2008,113:D08118
|
被引
14
次
|
|
|
|
16.
赵亮. 青海省三江源区人工草地生态系统CO_2通量.
植物生态学报,2008,32(3):544-554
|
被引
23
次
|
|
|
|
17.
李春. ChinaFLUX CO_2通量数据处理系统与应用.
地球信息科学,2008,10(5):557-565
|
被引
59
次
|
|
|
|
18.
温学发. 基于涡度相关技术估算植被/大气间净CO2交换量中的不确定性.
地球科学进展,2004,19(4):658-663
|
被引
21
次
|
|
|
|
19.
Zhao L. Diurnal, seasonal and annual variation in net ecosystem CO_2 exchange of an alpine shrubland on Qinghai-Tibetan plateau.
Global Change Biology,2006,12(10):1940-1953
|
被引
66
次
|
|
|
|
20.
Falge E. Gap filling strategies for long term energy flux data sets.
Agricultural and Forest Meteorology,2001,107(1):71-77
|
被引
100
次
|
|
|
|
|