【作者】 史小红；

【导师】 李畅游； 刘廷玺；

【作者基本信息】 内蒙古农业大学 ， 农业水土工程， 2004， 硕士

【摘要】 本文以科尔沁沙地为研究区，共布设172个调查试验点。于2002年6月～11月间对不同地形状况不同地貌类型区进行了野外地表植被状况、植物根系发育状况、土壤层及植被根系层水分状况的实地调查试验，并采取了土壤样本，进行了土壤物理化学特性、土壤养分状况的室内实验。据此，分析出以下结果：1）科尔沁沙地土壤大多属于高危风蚀土壤，其机械组成、物理化学性质在不同地貌类型中存在着显著差异并具有规律性的变化特征。2）沙地不同地貌类型区植被演替系列共分为：①沙生、②湿生、③撂荒地、④盐生、⑤放牧、⑥天然林这6个演替系列。影响植被演替的主要因素有气候条件变化、土壤水分养分动态、区域植被分布特点、人为因素的干扰、牧压梯度等外因条件以及植物本身相互间的竞争、适者生存的内在因素。3）科尔沁沙地不同地貌类型区土壤水分的空间变异性主要受土壤性质、地表植物形态、地下植物根系分布、降水、蒸发以及地下水埋深的影响。地下水埋深较浅的固定半固定沙丘按含水率变化趋势，可将地下水面以上土壤层分为四个变化带。地下水埋深较大的固定半固定沙丘土壤含水量的总体变化趋势是由上到下逐渐增大。流动沙丘在地表下180cm深度以内，土壤水分总体变化趋势为由表层向下逐渐增加到峰值点后，向下平稳或缓慢减小，在180cm深左右有一相对较干燥的干沙层，而后又逐渐增加，呈非饱和变化增加趋势。受沙化影响的甸子地土壤纵剖面可分为4个区域。未受沙丘侵蚀的甸子地可分为三个区域，即没有表层干沙区。在地下水浅埋条件下，土壤水分的来源主要为降水补给和地下水通过毛管上升的补给水分，在地下水埋深较大的沙丘中土壤水分的主要来源为降水和凝结水补给。更多还原

【Abstract】 This paper regards Horqin sandy land as the studying area,including totally 172 inquired experiments points.The plants condition,the roots growth condition of plants,the humidity condition of soil layer and plant roots are made on-site inspected experiments in the different geography type and different ground condition from June to November in 2002. We carried out the experiments on soil physics and chemistry characteristics and soil nutrient condition by adopting soil samples.As a result, getting the following results:1)Soil of Horqin sandy land mostly belongs to the eclipsed soil,there are the remarkable difference and regulational change about its machine constitutions, the physics and chemistry characteristics in different geography types.2)A different geography of plant evolution is divided into follows:①livings of the sand②the wet living③the wasteland④livings of the salt⑤pasturing⑥natural wood.The primary factors affecting evolution contain weather variety, soil humidity and nutrient, the characteristics of district plant,artificial factors and herd etc,besides mutually competition for the body plants and internal factors for existing. 3)Soil humidity variations for different geography soil in Horqin Sandy sand are affected primarily by soil condition, plant condition,rain,evaporate and deepth in groundwater.In the fixed sand dune and half fixed sand dune in shallow groundwater, there are four districts among the soil from the underground watertable to the soil surface.The total variety trend about soil water content is gradually augment from top to bottom ,in the fixed and the half fixed sand dune,where the groundwater of them is deep.The total variety trend in humidity from surface layer to a depth range (180cm)of research on flowing sand dune augment gradually from surface layer to summit value,then gradually decrease slowly,until reaching a relately dry sand layer, at last increase gradually and get unsaturated variety trend. According to the soil water development on the humidity ground,there are four areas.On the condition of the shallow groundwater the source of soil water are mainly rain and groundwater,however,in sand dune main source of the soil water are rain and condensening water.更多还原