Diatoms In Southwestern Mountainous Area Of China

As one of the World’s34biodiversity hotspots, Southwestern mountainous area of China has variable geographical environment and special climate system. Therefore extremely rich natural resources and biological species are existed. In this paper, we identified the diatom species, including endemic species of this area, it supplied new data for diatom taxonomy, ecology and bio geography of the world. From2006to2010, diatom samples were collected from Southwestern mountainous area of China. Taxonomical and flora of the diatom were presented, as follows:1. Totally112samples were observed and photographed.204species and32varieties were identified belong to3classes15orders30families and66genera.21species were newly recorded in China. Morphological descriptions and ecological characters were given for each species. LM images were given for all the species, and SEM images were given for part of them.776images were attached in this study.2. Taxonomical characters of the genus Halamphora were studied in particular.10species were identified in this area, among them,4are new species and3are newly record species. Meanwhile, all the Halamphora species recorded in China had been revised.3.The diatom population and distribution were compared within different sites and habitats. Diatoms in southwestern mountainous area of China had a high diversity at the level of genera, totally66gencra were observed. Most of them were found in Bacillariophyceae with50genera; in Coscinodiscophyccae only5genera9taxa were observed;11genera23taxa were observed in Fragilariophyceae. As the most abundant genus,17taxa were observed in Pinnularia, following with Naviculu16taxa, Cymbella15taxa, Halamphora10taxa, Nilzschia and Surirella9taxa respectively. Most of the taxa are uncommon species.