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为了解干涸湖底不同区域风蚀作用下蒸发盐动态变化的分异特征,选择西北干旱区艾比湖干涸湖底为研究区,选取西北部间歇性干涸湖底(S1)、湖滨沙丘(S2)、东南部历史时期干涸湖底(S3)3个典型区域,对干涸湖底不同区域沉积物蒸发盐总盐含量的变化特征及其对风蚀的响应分异进行了研究。实验结果表明:①不同区域蒸发盐含量差别较大。三个研究区中S1表层蒸发盐含量最高,可达101.0 g·kg~(-1);S3含量次之,表层最高时为47.3 g·kg~(-1);而S2表层含量最高仅为40.0g·kg~(-1)。②S1、S2、S3三个研究区蒸发盐含量随时间变化表现出相同的特征。6月份含量最高,随季节的变化趋势为从6—10月份逐渐降低。在不同的季节随着深度增加,含量均呈现降低的趋势,即不同地点不同时间0~50 cm各层含量均表现出降低趋势。③蒸发盐含量对风蚀的响应特征具有明显的区域差异和复杂性。在风蚀作用下,S1研究区未覆盖区域蒸发盐含量明显高于覆盖区域,S2研究区的含量对风蚀的响应特征比较复杂,而S3未覆盖区域含量低于覆盖区域,与S1研究区对风蚀的响应特征相反。不同区域不同的地下水埋深、沉积物质地、植被特征及迥异的风蚀机理是造成蒸发盐含量差别及不同风蚀响应特征的主要因素。
In order to understand the characteristics of the dynamic variation of evaporating salt in different regions of the dry lake, the dry lake bottom of Aibi Lake in the arid region of northwest China was selected as the study area. Intermittent dry lake bottom (S1), lakeshore dune (S2) and southeast During the historical period, three typical areas of dry lake bottom (S3) were studied. The variation of total salt content of sediment evaporation in different areas of dry lake and its response to wind erosion were studied. The experimental results show that: ① different regions of the evaporation of salt content vary greatly. Among the three studied areas, the content of evaporating salt in the surface of S1 was the highest (101.0 g · kg -1), followed by that of S3 (47.3 g · kg -1), and the highest content of S2 40.0g · kg -1. ②S1, S2, S3 evaporation of the three study area changes with time showed the same characteristics. The highest content in June, with the seasonal change trend from 6-10 months gradually decreased. In different seasons, with the increase of depth, the content showed a decreasing trend, that is, the content of 0 ~ 50 cm in different locations at different times showed a decreasing trend. ③ The response characteristics of evaporized salt to wind erosion have obvious regional difference and complexity. Under wind erosion, the content of evaporating salt in the uncovered area was significantly higher than that in the covered area in the S1 study area. The response of the S2 area to wind erosion was rather complicated, while the uncovered area in the S3 area was lower than that in the covered area. The opposite of the response characteristics. Different groundwater depths, sediment texture, vegetation characteristics and different wind erosion mechanisms in different regions are the main factors contributing to differences in evapotranspiration and different wind erosion response characteristics.