毛乌素沙区风沙土机械组成及含水率的季节变化  

The Mechanical Composition and Seasonal Wat er Content of Aeolian Sandy Soil in Mu Us Sandy Area

作　　者：张国盛[1] 王林和[1] 董智[1] 李玉灵[1] 

机构地区：[1]内蒙古林学院林学系

出　　处：《中国沙漠》1999年第2期145-150,共6页Journal of Desert Research

基　　金：内蒙古自治区科委攻关项目

摘　　要：以定位观测资料为基础，对毛乌素沙区０～１００ｃｍ层内流动风沙土、天然油蒿和臭柏灌丛及沙柳和樟子松人工林下风沙土的含水率和机械组成进行了研究。结果表明，整个生长季节流动风沙土的含水率较稳定，年平均值在３．０％左右；油蒿、臭柏、沙泖和樟子松下的固定、半固定风沙土含水率变化较大，年平均值为１％～２％。风沙土含水率主要受降雨、植物蒸腾和土面蒸发的影响，其垂直分布可分为０～１０ｃｍ的干沙层和１０～１００ｃｍ的活跃层；季节变化表现为４～６月和９～１１月的失水期、７～８月的降水补给期、翌年４月以前的冻结滞水期。Water is a main factor which limits agriculture and animal husbandry develop ment, desert control and afforestation. Studying the water dynamics has theoretical and practical significance for afforestation under water balance condition . Based on the site observation in 1997, this paper studies the water content of aeolian sandy soil within 0￣100 c m layer below the surface. The aeolian sandy soil samples are from shifting sand dunes, natural shrub lands of Artemisia ordosica and Sabina vulgaris , and planted forest lands of Salix psammophila and Pinus syvistris var. mongolica . During the whole growth period, the trend of water content in aeolian sandy soil is declinning from top to bottom. The moistur e content of mobile aeolian sandy soil is much stable with mean content about 3%, which is favorable for plants growth. The water content in fixed a nd semi fixed aeolian sandy soil with plants growing on varies more greatly; the annual mean content is 1%￣2%. The water content of aeolian sandy soil is mainly affected by precipitation, plant transpiration and soil evaporation. During the arid period from April to July and September to October, the vertical distribution of aeolian sandy soil moisture exists two distinctive layers: surface dry sand layer within 0￣10 cm and active soil moisture layer within 10￣80 cm. Under the shrubs of Artemisia ordosica, Sabina vulgaris and Salix psammophila , the water content within 0￣50 cm layer where roots distribute thickly fluctuates i n a greater range than that under the layer. But the contrary result is obtained in Pinus syvistris var. mongolica land. The aeolian sandy soil moisture reachs its maximum during the rain season(From July to August). Based on the seasonal variation of aeolian sandy soil moisture,it can be divided into three phase: the soil moisture lose phase from April to June and September to November; the refilling phase from July to August; the freezing water logged phase after August in thi s year

关 键 词：风沙土 土壤含水率 季节变化 沙区 

分 类 号：S152.3[农业科学—土壤学] S152.75[农业科学—农业基础科学]