Study On Flora And Ecology Of Plants In Beijing Huaisha-Huaijiu River Nature Reserve

Beijing Huaisha-huaijiu River Nature Reserve belonged to wetland ecosystem nature reserve, which lied in Huairou borough of Beijing. There were endangered animal (Megaiobatrachus dayidianus as an example) and rare fish such as Pungituis sinensis distributing in the drainage area. But the algae and vascular plants which supplied oxygen and food to aquatic animals were not reported as yet. From March 2004 to March 2005, freshwater algae and vascular plants were collected and identified from Huaisha-huaijiu River on purpose of analyzing the flora composition and ecological distribution for the first time.The results showed that there were 226 species (including varieties and forms) belonging to 105 genera and 9 phyla, in which Bacillariophyta, Chlorophyta and Cynaophyta were dominant in the reserve and algae belonging to Euglenophyta, Pyrrophyta, Xanthophyta, Rhodophyta, Chrysophyta. Cryptophyta were seldom. 11 families, 83 oligo-species genera and 13 species of algae were dominant and made up of the principal part of the algae flora composition at family, genus and species level.Influenced by physical property and chemical substance composes of the water body, there were some differences in the number of species and the density of algae among a year and all the sampling sites. The species number of Jul. (160 species) was the most and that of Jan. (81 species) was the least in each month. The number of species in Headwaters of Huaijiu River( 147 species) was the most among all the sampling sites and that of Dongtai (99 species) was the least. As for cells density, some dominant species such as Osicillatoria, Melosira, Nitzschia, Scendesmus quadnicanda etc. were the predominance component whether the temperature was condign. Some algae such as Asterionella, Pediastrum and Ulothrix were abundant in fitting temperature condition and poor in unseemliness condition.We also have used a serial of assessing indices, such as the saprobic system, contaminative index,diatom index, Lloyd-Ghelardi uniformity index and integrative biology index, to evaluate the waterquality of Huaisha-huaijiu River Nature Reserve. The water quality was changing from oligosaprobic(os ) to a-mesosaplobic ( α-ms ) in each sampling site and month. On the average of integrative biologyindex, the water quality of reserve was approaching to β-mesosaprobic. Comparing each sampling sitewith average of integrative biology index, sampling sites at Huaijiu River were better than Huaisha River.The water quality of Headwaters of Huanjiu River was the best and Dongtai of Huaisha River was theworst. Comparing each month with average of contaminative index, the water quality of Jan., Feb., Nov.and Dec. were better than the other months. The distribution orderliness of water quality was upriver andlower-river better than middle-river in Huaijiu River and lower-river better than upriver in Huaisha River.In addition, the composition of algae as food for Zacco platypus was investigated. 45 genera of algaewere identified, which belonged to 5 phyla. Algae species of Bacillariophyta and Chlorophyta weredominant among them. As for cells density, species of Bacillariophyta was the most. That indicatedZacco platypus had selectivity on eating algae and the algae quantity they could obtain had a direct ratiorelation to the cells density at a certain extent.Based on more than 600 vascular plant specimen collected from Huaisha-huaijiu River Nature Reserve, 187 species (including varieties) of algae were identified, which belonged to 75 families and 152 genera. 13 dominant families took 17.33% of the total families consist of 52.94% species, which were main part of the flora. Mono-genus and monotypic families were abundant and shared 62.67% and 53.33 % of the regional total families. Further more, monotypic genera also took the dominant place with 86.18% of the total genera. That reflected the complexity of the flora and obvious polarization among the genera.According to the method about the division of life form by Drude, the style of vascular plants in the region could be divided into 5 types : tree, shrub, semi-shrub, liane, perennial herbage, biennial and annual herbage. The herbaceous vascular plants were prominent which took 85.41 % of the total species. That revealed the distinctive character of vegetation in the north temperate region.On the areal-types of families, Tropics and temperature types were pretty much the same thing at the quantities. That showed some tropic origin of this flora in a way. On the base of the opinion of Wu Zheng-yi and Qin Ren-chang about the areal-types of genera of seed plants and ferns, the 152 genera in the region fall into 13 types. The temperate elements, including North temperate elements, East Asian and North American Disjuncted elements, Old World temperate elements, Temperate Asian elements and East Asian elements take the leading position, took 45.90% of all genera. That appeared evident temperate characteristic and accorded with the geographical location and climate condition of the nature reserve.The aquatic vegetation could be classified into emergent subtype, floating-leaved subtype and submergent subtype, including 13 main plant communities such as Form. Typha angustifolia, Form. Azolla imbricata, Form. Potamogetondistinctus, Form. Batrachium trichophyllum etc. The terricolous vegetation can be separated into coniferus forest, deciduous broad-leaved forest, deciduous broad-leaved shrubland and meadow, including 8 communities such as Form. Pinus tabulaeformis, Form. Populus tomentosa, Form. Spiraea trilobata. Form. Pilea mongolica etc.According to the utilization of the vascular plants in the nature reserve, resource plants might be grouped into 8 categories. There were 128 species could be using for medicinal plants, 21 species for food, 25 for feedstuffs, 11 species for timber, 23 species for industry material, 11 species for ornamental, 5 species for green manure. On the side, there were 4 species plants bore other value, including using for honey resource, holding water and soil etc.In addition, the checklist of freshwater algae and vascular plants, 28 tables, 10 figers, 11 plates and 137 references were provided in this thesis.