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题名	古尔班通古特沙漠风沙土土壤蒸发特征研究
作者	翟翠霞
学位类别	硕士
答辩日期	2007
授予单位	中国科学院．新疆生态与地理研究所
导师	马健，新疆生态与地理研究所
关键词	土壤蒸发
其他题名	Soil evaporation of aeolian sandy soil in Gurbantunggut Desert
中文摘要	干旱条件下，水是影响自然环境变异的最重要因子。土壤水分含量决定着植物生存与生长，对遏止沙漠化危害至关重要。土壤水分是将降水、土壤和植被对水分平衡的作用与水分平衡对植被的动态影响综合起来的关键因子。干早、半干早沙地降水先天不足，而潜在蒸散量大，降雨入渗到土壤中并被储存的水分是该地区植被生长、发育的主要水源。沙地土壤蒸发是大气降水的一种无效散失，它的大小直接决定着降水转化为有效土壤水的效率，从而间接决定了植物可利用水分的多寡。在降水稀少的沙漠地区，定量认识土壤蒸发量的大小和其所占降水的比例的多少显得尤为重要。本论文于2004年在植物全生长期（5-9月），应用自制的微型蒸渗仪(Micro-Lysimeter)测定了风沙土（有结皮覆盖的丘间低地和裸露沙丘顶部）和对照的荒漠盐碱土的土壤蒸发。结果表明：在相似的气象条件下，风沙土区的丘间低地和荒漠盐碱土的日平均蒸发量分别约是裸露沙丘（风沙土区）的2倍和3倍。整个生长期裸露沙丘的累积蒸发量为18.7 mm，丘间低地为38.8 mm，荒漠盐碱土为 52.1 mm。根据整个观测期的累积蒸发量和累积降雨量计算得出的蒸发降雨比分别为：裸露沙丘0.20，丘间低地0.42，荒漠盐碱土0.62，表明裸露沙丘由降水转化为土壤水而储存的比率最高。同时，从数据分析中可以看出：在风沙土区0-5 cm土层的含水量对土壤蒸发起决定作用，而盐碱土区的土壤蒸发则受到更深层次土壤水分的影响。裸露沙丘低的土壤蒸发、高的降水转化效率，为植被恢复奠定了良好的基础。因此，裸露沙丘的低蒸发量可以视为植被状况对生态水文过程的一种良性反馈。Abstract:Water is a key factor influenced the environment variation in arid and semiarid region, soil moisture content is the most important limitary factor to plant growth, also have the probability to prevent aggravation of the desertification .soil moisture is the essential to combine the effect of precipitation, soil and vegetation on water balance with the dynamic impact of water balance on vegetation. Precipitation is inadequate in the arid and semiarid sandy land, but the potential evapotranspiration is high, so the main water source for plant growth is the deposited soil moisture. Sandy soil evaporation is an ineffective loss of rainfall, it directly determines the amount of rainfall that will eventually becomes soil water, which is available to plants. In the desert area where rainfall is rare and valuable, study on soil evaporation and its proportion of the rainfall is more important than other region. Experiments were carried out in the whole growing season of 2004 to evaluate the evaporation of aeolian sandy soil and heavy texured saline desert soils using micro-lysimeters. The results indicated that the average daily evaporation of the inter-dune and saline soils are 2 times and 3 times, respectively, of the evaporation from the bare sand dune soil under similar climatic and soil water conditions. Accumulated evaporations from bare sand dune, inter-dune lowland and the desert saline soils for the whole growing season were 18.7 mm, 38.8 mm and 52.1mm, respectively. Based on the accumulated evaporation and precipitation, the evaporation-precipitation ratios for the whole growing season were calculated as 0.20, 0.42 and 0.62 for bare sand dune, inter-dune lowland and desert saline soils, respectively; indicated that bare sand dune has the highest storage ratio for precipitation. Close correlation between soil evaporation between soil water content at 0-5 cm (R2 > 0.90 for sandy soils, R2 ~ 0.81 for heavy textured saline soil) indicated that the soil evaporation was determined by soil water content in top soil layer for sandy soils, and for the heavy textured saline soil, it was also influenced by soil water content at the layers below. Low evaporation, high storage ratio to rainfall in bare sand dune, creates favorable condition for vegetation restoration, and this may be considered as a positive feedback of local vegetation conditions towards eco-hydrological processes.
语种	中文
学科主题	自然地理学,农学
公开日期	2010-11-12
页码	共63页
内容类型	学位论文
源URL	[http://ir.xjlas.org/handle/365004/7892]
专题	新疆生态与地理研究所_中国科学院新疆生态与地理研究所(2010年以前数据)
推荐引用方式 GB/T 7714	翟翠霞. 古尔班通古特沙漠风沙土土壤蒸发特征研究[D]. 中国科学院．新疆生态与地理研究所. 2007.

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