青海湖北沙柳河镇薄土层含水量与水分平衡

通过对青海湖北刚察县沙流河附近厚度15 cm、20 cm、30 cm、40 cm薄土层的土壤含水量的测定,研究了此区土壤水分含量和水循环等问题.研究结果表明,沙柳河附近40 cm以上土层以粗粉砂为主.薄土层含水量从表层向下呈现出低-高-低的变化趋势,这是表层水分易于蒸发、中部蒸发较少和下部水分易于入渗流失的结果.虽然该区土壤在0.40m以上含水量较高,没有土壤干层发育,但如按1 m厚度土壤和1.5m厚度土壤计算,该区薄土层水分不足,并由中度干层和严重于层发育,±壤水分为负平衡.与厚土层相比,该区薄土层分布区土壤水分存在形式多为薄膜水,含水量较低,蓄水量少,土壤水库调节能力差,易于发生荒漠化,这样的地区应该是青海湖流域生态环境保护的重点地区.

Soil Moisture Content and Balance in Thin Soil at Shaliuhe Town in the North of Qinghai Lake

According to the determination of the thin soil moisture of Shaliuhe town in the Gangcha county of the northern Qinghai lake,the thin soil below the surface-15 cm,20 cm,30 cm,40 cm soil layer.The paper studies the soil moisture content,its impacts on vegetation development and water cycle.The result shows that the soil in the studied area is mainly coarse silt and the soil moisture from the surface exhibits a low-high-low variation trend.,because the surface water is easy to evaporation,the water evaporation in the central soil is less and the infiltration in the lower losses much water.Although the soils above 0.40 m in this area has high water content and does not develop soil dry layer,but by the calculation of 1 m and 1.5 m soil,in the area,the thin soil moisture is insufficient,develop the moderate and severe dry layer,the soil moisture is negative balance.Compared with the thick soil layer,the water in thin soil exists in the form of multiple thin film of water,with lower moisture,less water consumption,and Soil reservoir has bad regulative ability,as a result,this area easily occurs desertification,it should be the key area of the ecological environment protection in The Qinghai Lake basin.