黄河三角洲典型植被与地下水埋深和土壤盐分的关系

Relationships between typical vegetations,soil salinity,and groundwater depth in the Yellow River Delta of China

土壤盐分和地下水埋深是影响黄河三角洲植被发育和分布的重要因素．本文通过野外调查与统计分析，研究了黄河三角洲区域典型植被（翅碱蓬．柽柳、刺槐、芦苇和棉花）、地下水埋深、土壤盐分之间的关系．结果表明：研究区地下水埋深显著影响土壤盐分，平均影响系数为0．327，地下水埋深在0．5—1．5m的土壤盐渍化最严重；整个研究区内植被发育较差，其中，研究区78％面积的归一化植被指数（NDVI）〈0．4，地下水埋深、土壤盐分对天然植被分布有显著影响；土壤盐分对研究区翅碱蓬-柽柳、刺槐、芦苇及棉花NDVI的影响显著，地下水埋深对翅碱蓬-柽柳NDVI的影响显著，对芦苇、棉花、刺槐NDVI的影响不显著．

Soil salinity and groundwater depth are the two important factors affecting the vegetation growth and distribution in the Yellow River Delta. Through field investigation and statistical analy- sis, this paper studied the relationships between the typical vegetations （Suaeda heteroptera-Tamar- ix chinensis, Robinia pseudoacacia, Phragmites australis, and cotton） , soil salinity, and groundwa- ter depth in the Delta. In the study area, groundwater depth had significant effects on soil salinity, with the average influence coefficient being 0. 327. When the groundwater depth was 0.5-1.5 m, soil salinization was most severe. The vegetation growth in the Delta was poorer, with the NDVI in 78% of the total area being less than 0.4. Groundwater depth and soil salinity had significant effects on the vegetation distribution. Soil salinity had significant effects on the NDVI of R. pseud- oacacia, S. heteroptera-T, chinensis, P. australis, and cotton, while groundwater depth had signif- icant effects on the NDVI of S. heteroptera- T. chinensis, but lesser effects on the NDVI of P. australis, cotton and R. pseudoacacia.