Study On Biodiversity And Protection Of Karst Wetland In Huixian, Guilin

Based on a great deal of field investigations of Karst Wetland in Huixian, wetland type and distribution, community type and composition,wetland plant flora, bio-diversity, interspecific relationship, wetland conservation status and strategy were analyzed and discussed in this paper. The results abtained were as follows:1. The Karst Wetland in Huixian could be subdivided into 4 classes and 11 types. In whcich, 3 classes were belonging to natural wetland and 1 class was belonging to man-made wetland. The common wetlands were Paddy field, Lake, Swamp and Fishpond.2. There were 4 vegetation types and 33 formation types in Karst Wetland in Huixian. Most of the plant communities were single excellent communities; the diversity level was not high, taking emerged plant communities and submerged plant communities as main, the community structure was simple. So its diversity level was not high and community structure was simple. The biomass was one of the most fundamental and important quantitative characteristics on wetland vegetation study. The preliminary study was showed that there were great differences among different communities. Biomass of Cladium chinense was largest in emerged plant community, being 2599.10 g?dw/m2. And Vallisneria denseserrulata was largest in submerged plants community, being 966.88 g?dw/m2. We presumed that it was possibly correlatied with the water depth, water flow velocity and species composition of communities. In order to get further understanding about the structure and succession of plant communities in the wetland, we investigated the relationship among plants and divided ecological species groups. The results were showed that the relationships among plants are negativly correlatied. It indicated that plant species composition was not stable. And succession of community was rapidly performing in Karst Wetland in Huixian.3. A total of 133 species of wetland plants belonging to 78 genera and 39 families were found in the Karst Wetland of Huixian, Guilin. In which, 1 specie belonging to 1 genera and 1 family was bryophyte plants, 4 species belonging to 4 genera and 4 families were pteridophyte plants, 128 species belonging to 73 genera and 34 families were angiosperm plants. The dominant wetland plants were angiosperms with 49 species dicotyledonous plants belonging to 33 genera and 21 families and 79 species monocotyledonous plants belonging to 40 genera and 13 families. The dominant families were Gramineae and Cyperaceae, which contained 15 and 7 genera respectively. In the Karst Wetland, the dominant genera were polygonum, eleochalis and cyperus, respectively containing 6 species. The Wetland plants in Huixian Karst area could be subdivided into hygrophytes and aquatic plants on the basis of their life-forms and ecological characteristics. In which, hygrophytes could be divided into 3 life-forms, namely emerging plants, floating plants and submerged plants. The majority were emerged plants, whose species count 77, and account for 57.46%. There were 10 florae of the wetland plants, generally with obvious characters of tropical and subtropical species4. From the basic research, there were 56 species and 35 genera and 7 families of anabaena. And most of algae are of common species of freshwater algae, except a small number of special species. There were mostly oligotrophic algae in autumn, less indicator species. Some species of Cyanophyta was dominant in water, which showed that water was eutrophic.5. Current survey was showed that there were 30 species fishes belonging to 13 families and 7 orders, 67 species birds belonging to 29 families and 10 orders, including 35 species migratory birds (33 species winter residents and 2 species summer residents), 2 species travelling birds, 30 species resident birds and 17 species other animals. Of which Aix galericralata, Accipiter nisus and Falco tinnunculus are the national protective birds of Level 2, because the encounter rate was low and their population number was small, it was important to take effective measures to protect them.6. Plant resources in Huixian karst wetland could be divided into 3 categories and 20 sub-categories on the base of function.7. It was showed that there were 324 species and 239 generas and 100 families of terrestrial plants found around the wetland, of which there were 2 families and 2 generas and 2 species of bryophyte, 22 species and 17 generas and 11 families of ferns, 2 species and 2 generas and 2 families of gymnosperm, 251 species and 180 generas and 75 families of dicotyledon, and 47 species and 38 generas and 10 families of monocotyledons.8. It is a great significance to conduct protection on the biodiversity conservation in Huixian karstic wetland, and the works should include water conservation, water purification, research, science education and promotion, eco-tourism, etc, therefore, it is important to protect the bio-diversity for Karst Wetland in Huixian which is not optimistic at present. Because the reducing wetland area by agriculture and fishery, deteriorating wetland ecosystem by continuously serious environment pollution and invasion of alien species and extension of drought.Therefore, in this paper the author bring forward proposes and targeted recommendations as follows:a increase promotion on protection of wetland biodiversity conservation; strengthening the management, preventing the wetland resources exploiting excessively; speeding up construction of wetland nature reserve; perfecting the laws and regulations of wetland protect; strengthening the study on wetland, setting up a wetland monitoring system; performing the wetland recovery with measured strokes.