| 引用本文: | 李 稚,汪 洋,王志成,等.1982―2012年西北干旱区蒸散发组分时空变化分析[J].灌溉排水学报,2018,37(7):120-128. |
| LI Zhi,WANG Yang,WANG Zhicheng,et al.1982―2012年西北干旱区蒸散发组分时空变化分析[J].灌溉排水学报,2018,37(7):120-128. |
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| 摘要: |
| 【目的】为我国西北干旱区水资源承载力评价、水资源管理和生态规划提供科学依据。【方法】从西北干旱区蒸散量及其组分（土壤蒸发、冠层截留蒸发、植被蒸腾）的时空变化入手，结合遥感反演技术，重点解析了西北干旱区山、盆相间地貌格局下的实际蒸散发总量及其组分变化的趋势及时空分异规律。【结果】1982―2012年西北干旱区实际蒸散发（Eta）以-0.053 mm/a的速率总体略呈下降趋势。蒸散发3个组分中，土壤蒸发（Es）占蒸散发总量的比例最大，约占总蒸散量的76%，是蒸散发总量下降趋势的最主要和最直接贡献分量；土壤蒸发（Es）约在2000年发生了一个不明显的转折，由2000年之前以-0.518 mm/a的速率略微下降转变为以0.595 mm/a的速率略微上升。而植被蒸腾（Ec）和冠层截留蒸发（Ei）分别占总蒸散量的22.7%和1.3%，在1982―2012年分别以0.124 mm/a和0.007 mm/a的速率呈现上升趋势。【结论】西北干旱区蒸散发3组分所占比为土壤蒸发（Es）>植被蒸腾（Ec）>冠层截留蒸发（Ei），伴随着2000年以来区域的跃变式高温波动，自2000年以来，土壤蒸发（Es）加大，0～10、10～40 cm的浅层土壤水散失加大，荒漠植被经历了先增加后退化的过程，原本就十分脆弱的浅根系荒漠植被覆盖区面临更严峻的生态干旱风险。 |
| 关键词: 蒸散发组分； 土壤蒸发； 植被蒸腾； 冠层截留蒸发； 西北干旱区 |
| DOI：10.13522/j.cnki.ggps.2017.0679 |
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| Spatiotemporal Variation of Evaporation and Transpiration from 1982—2012 in the Arid Valley Region in Northwest China |
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LI Zhi, WANG Yang, WANG Zhicheng, LI Weihong
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State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Science, Urumqi 830011, China; College of Pratacultural and Environmental Sciences, Xinjiang Agricultural University, Urumqi 830052, China; Xinjiang Tarim River Basin Aksu Management Bureau, Aksu 843000, China
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| Abstract: |
| 【Objective】 Measurements of terrestrial evapotranspiration and its components have important practical effect. Analysis of the influences of evapotranspiration components on regional ecology will provide a scientific basis for the development, utilization, and management of water resources and ecological planning.【Method】Based on the CSIRO remote sensing data for land use/cover change and evapotranspiration, this paper investigated the temporal and spatial variations of evapotranspiration and its components of soil evaporation (Es), vegetation transpiration (Ec), and vaporization of intercepted rainfall from vegetation (Ei) in the arid region of Northwest China. 【Result】 Additionally, the paper analyzed the impacts of the evapotranspiration components on the regional ecological environment. The total actual evapotranspiration showed a decreasing trend at a rate of -0.053 mm/a. Evaporation from soil (Es), which was the main and most directly contributing component, accounted for 76% of total actual evapotranspiration. Soil evaporation exhibited a slightly decreasing trend at a rate of -0.518 mm/a up to the year 2000, after which it reversed to a slightly upward trend at a rate of 0.595 mm/a. Transpiration from vegetation (Ec) and vaporization of intercepted rainfall from vegetation (Ei), which accounted for 22.7% and 1.3% of total actual evapotranspiration, respectively, showing increasing trends at a rate of 0.124 mm/a and 0.007 mm/a, respectively, over the past 30 years. 【Conclusion】 The proportion of evaporation from soil (Es) in the three evapotranspiration components is the biggest in the arid region of Northwest China, and followed by the transpiration from vegetation（Ec）and intercepted rainfall from vegetation（Ei）. With regional jump warming in 2000, evaporation from soil (Es) increases, and soil moisture loss occurs mainly in the shallow layer and desert vegetation with shallow roots reversed a declining trend since the early 2000s, all of which will result in the water-based ecosystem becoming increasingly fragile in the arid region of Northwest China. |
| Key words: evapotranspiration components; evaporation from the soil (Es); transpiration from vegetation (Ec); vaporization of intercepted rainfall from vegetation (Ei); arid region of Northwest |
