天津滨海新区自然湿地植物分布与土壤理化性质的关系

Relations between Plant Community Characteristic and Soil Physicochemical Factors in Natural Wetlands of Binhai New District,Tianjin

于2008年7～9月,采用样带取样法对天津滨海新区湿地植被群落和土壤理化性质进行调查,并应用典范对应分析法(Canonical Correspondence Analysis,CCA)对滨海新区湿地植被群落类型及其分布与土壤理化性质之间的的关系进行了研究。典范对应分析结果表明,不同群落类型在排序轴上的位置反映出与土壤理化性质的关系,土壤含水量和含盐量的差异是形成滨海新区湿地植物分布格局的重要因素,其次是速效氮含量,而pH、有机质、速效钾、速效磷的影响较小。土壤理化性质因子在一定程度上决定了群落在排序空间中的位置,也决定了群落物种组成这一基本的群落特征。优势种的排序结果与样方的结果极其相似,说明优势种的分布格局在一定程度上决定了群落类型的分布格局。

In recent years, research on the connection between plant community and soil factors have become the hot pot because of its important ecological significance. Most of the studies focused on mountainous Districts and forests, little has been conducted on wetlands. The wetlands of Binhai New District were studied in this paper because of its unique environmental characteristics. High salt content in the soil and plentifuls are the most important properties of this District. With large - scale development and construction, the natural wetlands of Binhai New District were decreased largely and rapidly, the survival of salt plants has been threatened. The research on salt plant community and local soil physicochemical factors has significant importance for wetland protection and restoration. The wetlands of Binhai New District were divided into four types： coastal wetland, river wetland, lake wetland and constructed wetland. Researches were focused on natural wetlands, especially river and lake wetlands, natural salt plants could hardly be seen in these Districts. Based on the investigation on plant community and soil physicochemical factors of Binhai New District using transects methods between July and September, 2008, the relationship between plant community and soil factors in Binhai New District had been researched. Plant collection were adopted by important values, which were measured by 1m × 1m quadrats. Soil physicoehemical factors were measured by titrimetric methods, flame luminosity methods, alkaline hydrolysis diffusion methods, lixiviating methods and heating methods. Canonical Correspondence Analysis （CCA） was applied to draw and analyze the species - environment and samples - environment two - dimensional ordination diagrams. 46 families, 135 genera, 232 species had been investigated, including 61 salt -tolerant species. According to water ecological type, the wetland plants divided into 4 subtypes ： aquatic plants, humidogene plants, meso - xerophytism and xerophytism. Soil physicoehemical factors could affect the characteristic of plant community in a complicated way in the analysis of the relationship between soil factors and plant community. The sorting among the 23 quadrates demonstrated that the position of different populations had close relations with soil physieochemical factors. Disparities between water content and salt content in the soil implied the most important factors in the formation of vegetation pattern of Binhai New District, available N content showed the second important factor, while pH, orgnic matter, available K and N were not so related with the vegetation pattern. The population positions and characteristic were determined by all these factors. The sorting of dominant species had similar results with quadrates, which proved that the dominant species patterns could decide patterns of population on some extent.