Research On Diversity Of Wetland Plants In Natural Reserves Of Shanxi Province

The wetland spermatophyte from flora and geographical elements, classification and ordination, species diversity of containing36wetlands of nature reserves in Shanxi Province are analyzed based on field quadrat investigation and previous materials from2009to2012. The purposes of this study were to understand the present situation of diversity of wetland plant and ecological relationships between species and environment, these results could be regarded as some theoretical basis for biodiversity protection in this area.The results obtained are as follows:1. There are294species of wetland spermatophyte on record, belonging to154genera and56families in the36nature reserves. In four life forms of wetland plant, there are278species of herbs, accounting for94.56%of the total species. Wetland plants are divided into7ecotypes, including269species of wet plants, making up91.5%of the total species, which is the main component of the wetland plants in nature reserves of Shanxi Province; there are88species of marsh plants and74species of hygrophytes, which constitute the edificators and dominant species of wetland vegetation of nature reserves in Shanxi Province. The widespread type is majority in the areal types of families with spermatophyte flora, with a total of20families; most of the plants are temperate types on the level of genus, with a total of82genera, accounting for53.25%of the total genera number, the temperate zone nature is obvious. The distribution type of seed plants flora is complete, among which, temperate element is superior in species number, up to160species, accounting for54.42%of the total species; there are40species endemism to China. There are2species of the wetland spermatophytes belonging to national-level or provincial-level key protected wild plants.2. Adopting TWINSPAN and DCA, the paper carried out quantitative classification and ordination of315plots of36Nature Reserve of Shanxi province containing wetland, divided the plots into18associations and discussed the character of coenology. The ordination results of the communities from DCA were as following: the abscissa axis of the DCA ordination from right to left reflected the change of water gradient; the corresponding vegetation types were the aquatic communitier, wet communities and wet-humidogene communities and it reflected the change of the dominant species’life form; the vertical axis reflected the change of underground water level which gradually increased from the upper to the bottom boundary of the ordination diagram. Moreover, the results of the114species’from DCA tow-dimensional ordination and315quadrats’ ordination showed the same trend. Analysis showed that the distribution patterns of the phytocenosis from Nature Reserve in Shanxi were mainly affected by the water gradient of the soil and the corresponding soil type.3. The species diversity of wetland plants communities from36natural reserves of Shanxi was studied with the diversity indices including species richness index (R), Simpson index (D), Shannon-Weaver diversity (H) and evenness index (E1) on the basis of field investigation. The results indicated that: the315samples were divided into18associations by TWINSPAN. The average R was between1-4.119, the average H was between0～1.165, the trends of both two indices were similarity. The average H of the herbaceous plant community was small, and this suggested that the diversity level of wetland plant communities in the natural reserves of Shanxi was lower. The average E1was between0.17～0.957. The two extreme values, the largest and smallest, were both from aquatic plant community, while the average E1of the other community of hygrophytes and hygro-mesophytes was in the middle. Among the36natural reserves, the average R of Sushui River Source Nature Reserve was the highest, while in that of Mian Mountain Nature Reserve was the lowest (R=1.5). The average H was between0.335～1.617. In general, the diversity index of the wetland plant communities of the natural reserves in south Shanxi was higher than that in the central and north Shanxi. E1was between0.501～0.984. There was a positive correlation between the species richness index, evenness index and diversity index.