银川平原土壤盐渍化与植被发育和地下水埋深关系

土壤盐渍化是制约银川平原内部植被生长最主要的生态环境地质问题，也是影响区域农业生产的第一障碍性问题。基于遥感数据，结合表层土壤含盐量及地下水位观测资料，对银川平原土壤盐渍化与植被和地下水的关系进行了定量研究。结果表明：随着表层土壤含盐量的增大，NDVI(归一化植被指数)逐渐减小，植被发育较好的区域土壤含盐量均小于3 g/kg；植被主要生长在没有盐渍化或轻微盐渍化的地区，在中度和重度盐渍化地区几乎没有植被发育；在枯水季节，研究区土壤盐渍化最严重的地下水位埋深为1.5 m，而土壤盐渍化较为严重的地下水位埋深范围为1~3 m。

Relationship between Soil Salinization and the Vegetation Growing,Groundwater Depth in the Yinchuan Plain

Soil salinization is one of the most important eco-environmental problems constraining the vegetation growth in the Yinchuan plain.It is the first obstruction for the regional agricultural production.Based on the remote sensing data,surface soil salt and groundwater table data,this paper studied the relationships between the soil salinization and the vegetation,groundwater depth in Yinchuan plain.The results indicated that the NDVI(normalized difference vegetation index)decreased with the increase of surface soil salt contents;and the vegetation growth is well developed as the surface soil salt content is smaller than 3 g/kg.The vegetation mainly grows in the area with no salinization or slight salinization;little vegetation grows in the area with moderate salinization and serious salinization.In dry seasons,the most serious salinization occurs when the groundwater depth is 1.5 m and the salinization is more serious as the groundwater depth is between 1 and 3 m.