The Distribution of Vegetation and Its Relationship with Environmental Factors in the Yellow River Estuarine Wetland

[ Objective] The aim was to study the distribution of vegetation and its relationship with environmental factors in Yellow River estuarine wetland. [ Method] According to the data of the plant sample investigation and the related environmental factors in Yellow River Delta National Na- ture Reserve in 2009 -2010, the plant community changes and its relationship with environmental factors in temperate estuary wetland were ana- lyzed. [Result] There was little vegetation in the Yellow River delta and the distribution of plant was influenced by environment. Judging from the vegetation structure, the vertical structure of vegetation in the supralittoral zone zone vegetation cover included arbor layer, shrub layer and grass layer. The importance of grass was larger than shrub and arbor. In the intertidal zone, the vertical structure of plants was divided into shrub and herb layers. Judging from the variety, the species in the supralittoral zone was higher than that in the intertidal. The first principal component elected by Principal Component Analysis better reflects the salt of the study area, and the second principal component better reflects nutrient information. Regression analysis showed a positive correlation between importance value and the total salt content and electrical conductivity. In other words, if the total salt content and electrical conductivity increases, the importance value rose. However, the diversity index decreased as the total salt con- tent and electrical conductivity increased. [ Conclusion] The study provided theoretical basis for the ecological protection of vegetations and formula- tion of regional policies.