Studies On Diatoms Of Chongming Island

Wetlands, which is very vast in our country, scatter mainly in cold temperate, tropical,the coast, the inland, the inland plateau, the mountains and so on, is a systematic important component of natural ecology contained rich alga resource among them. Chongming Island is located in Yangtze River estuary,and play a very important role in china, So far, bird, fish, zooplankton have been investigated, but the research of diatom is relative weakness. In this paper,preliminary investigation and study have been done about the diversity of diatom in Chongming Island and provide important data to algae resource investigations, diversity of algae and wetland ecology research to Chongming Island, also provides the basis data to our country's algae investigation.We have carried out four times of alga specimen collection at Chongming Dongtan in March , July and October 2008, January 2009. The light microscope is made use of observation on all specimens and take photos, unit making use of scanning electron microscope to observe and take photos, 169 taxa have been identified, including 148 species, 21varieties, which belong to 3 classes 18 orders 34 families and 58 genera. Among them 14 species and 3 varieties are newly recorded in China.The species composition and distribution of diatom in Chongming Dongtan were discussed preliminarily:1. Majority of species in Chongming Island are marine species and brackish water species, some freshwater species also appeared, some representative species of typical habitat also discovered.2. Chongming Island have diversity rich diatom species, the main characteristic is mainly of these taxa are general widespread species, most of all is the world's widely distributed species or scattering broadly in the Northern Hemisphere.3. In the habitat conditions, the occasional species are many, the dominant and common species are rare. In all taxa only 6 species obvious dominant species and these species are all present in autumn.4. In the four kinds of habitats, 73 taxa are identified in the area of bare beach. 61 taxa are identified in the area of Scirpus mariqueter community. 140 taxa are identified in the area of Spartina alterniflora and Phragmites australis community. 69 taxa are identified in the area of tridal creek. 5. Among four seasons, spring has the most abundant composition, 138 taxa are identified. In summer, 51 taxa are identified. In autumn, the species are less, 49 taxa are identified in total. In winter, 64 taxa are identified.