Similarity of the Floristic Characteristics of Different Coastal Wetlands in China

Coastal wetlands are biologically important landscapes and among the most vulnerable ecosystems on Earth. Floristic spectrum, correlation analysis, principal coordinate analysis (PCO) and cluster analysis were conducted to reveal the floristic similarity of different coastal wetlands from China. Results showed that:with the decrease in latitude, a decreasing trend was observed in the proportions of temperate elements at the genus-level, while those of tropical elements showed contrary patterns, which may be strongly correlated with their different ecological characters and energy distribution;compared with other coastal wetlands, the floristic Shannon-Weiner index showed obvious differences (1.430-2.154), while the Simpson index showed no obvious differences (0.662-0.842). Correlation was significant at the 0.01 level by correlation analysis, with coefficients between 0.369 and 0.989. A two-dimensional PCO scatter plot and dendrogram based on the floristic spectra of nine coastal wetland flora were drawn, with the coastal wetland flora divided into five groups. Distribution patterns and floristic similarities of the nine coastal wetlands from China were revealed accordingly. Results indicated that these methods objectively reflected the areal-type similarities of different coastal wetlands at the genus-level, which should improve our understanding of the floristic similarities of coastal wetlands.