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核心期刊论文目录 |
Evaporation properties of a revegetated area of the Tengger Desert, North China |
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出 版 社:Journal of Arid Environments |
发表时间: 2008, 72: 964-973 |
台 站:
沙坡头沙漠试验研究站
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作 者:张志山 |
点 击 率:4087 |
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关 键 字:Biological soil crusts; Microlysimeter; Lysimeter |
摘 要:Vegetation restoration is one of the most common methods for combating desertification in northern China. The planting of shrubs on the southeast fringe of the Tengger Desert had significant effects on hydrological cycles, especially on
the evaporation process. In this paper, a field experiment was conducted to investigate the effect of revegetation on
evaporation process in a desert. The presence of shrubs reduced percolation from a lysimeter to zero. Caragana korshinskii
Kom. showed greater evapotranspiration in the wetter of two study years, while Artemisia ordosica Krash. showed more
evapotranspiration in the drier year. This was attributed to their different root distributions. The microlysimeter
measurements showed that there was no significant difference in the evaporation rates between locations in the same
quadrat, which means that the sparse vegetation had little effect on soil evaporation under the canopy, and thus
modification of the microclimate was not a dominant factor in controlling soil evaporation in the revegetated desert area.
The difference in soil evaporation between bare sand and the revegetated area was caused mainly by the formation of
biological soil crusts. Simulated rainfall experiments showed that the crust had a retarding effect on evaporation under
very low rainfall (p5 mm), because its high proportion of finer particles slowed the evaporation rate, thus keeping the
water in the soil surface longer. However, it allowed a higher evaporation rate under higher rainfall conditions.
r 2007 Elsevier Ltd. All rights reserved. |
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