| 不同质地条件下土壤表层温度与土壤蒸发量的关系研究 |
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| 作者单位： | ;1.北京师范大学水科学研究院;2.城市水循环与海绵城市技术北京市重点实验室 |
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| 摘 要： | 土壤表层温度与土壤蒸发量有着紧密联系,土壤质地对二者均有着重要影响。【目的】探究不同质地土壤表层温度变化对土壤蒸发的影响。【方法】选取2种质地原状土(粉壤土与砂土),进行配比混合,得到5种不同质地土壤。测量1次性供水与充分供水条件下不同土壤的蒸发量、土壤表层温度数据、土壤砂粒量,探究不同质地条件下土壤相对蒸发量(RE)和土壤表层相对温度差(RT)的关系。【结果】①1次供水和充分供水条件下RT随着蒸发过程的进行逐渐增大,当蒸发过程至水汽扩散阶段时,RT趋于稳定;②随着土壤砂粒量增大,蒸发至水汽扩散阶段时对应的RT逐渐减小;③土壤质地相同情况下,RT越大,其RE越小,回归建立了二者的二次函数关系;④RT相同情况下,土壤中砂粒量越高,其RE越小。【结论】土壤中砂粒量的不同,使土壤孔隙、热容量等性质产生差异,导致蒸发过程中土壤温度及蒸发量变化出现规律性特点,RE与RT呈与含砂率有关的二次函数关系。
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| 关 键 词： | 土壤蒸发量 土壤表层温度 土壤质地 相对蒸发量 砂粒百分比 |
Study on Relation between Soil Surface Temperature and Soil Relative Evaporation of Different Soil Texture |
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| Institution: | ,College of Water Sciences, Beijing Normal University,Beijing Key Laboratory of Urban Hydrological Cycle and Sponge City Technology |
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| Abstract: | There are some critical relationships between soil surface temperature and soil evaporation, and the texture of soil affect those two variables.【Objective】This paper amis to explore the effect of soil temperature changes on soil evaporation in different textures.【Method】Five types of soil were produced by two kinds of soil whose texture were silty loam and sand with different proportion in this experiment. Each mixed soil was tested in situation of sufficient soil moisture and situation of non-sufficient soil moisture, the evaporation, soil surface temperature under those two kinds of situation and soil texture were measured. And the relationship between relative evaporation(RE) and relative difference of soil surface temperature(RT) in different textures were studied.【Result】①The relative difference of soil surface temperature(RT) increases with the procession of evaporation until the evaporation going to water vapor diffusion stage, and RT would be steady after that; ②In stage of water vapor diffusion, the relative difference of soil surface temperature(RT) reduced with the increasing of soil sand proportion; ③ When soil texture was the same, the relative evaporation(RE) reduced in a quadric relationship with the relative difference of soil surface temperature(RT);④The relative evaporation(RE) reduces with the increasing of sand percentage of soil when RT was a constant.【Conclusion】The difference of sand proportion in soil makes the difference of soil pores and heat capacity, which leads to the regularity of soil temperature and evaporation during evaporation, and the quadric relationship between relative evaporation and relative difference of soil surface temperature. |
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| Keywords: | soil evaporation soil surface temperature soil texture relative evaporation sand proportion |
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