Aquatic Plant Investigation And Evaluation Of Constructed Wetland

With the development of eco-city construction,wetland,as an important environmental resource,plays a positive role in urban development,and its attitude towards wetland has changed from destruction to protection and reconstruction;from protecting natural wetland to constructed wetland.The connotation of constructed wetland is constantly enriching the concept of urban ecological planning.As important producers in the urban constructed wetland ecosystem,aquatic plants not only create the rhizosphere environment for the microbial degradation of pollutants,but also play an important role in the connection and medium of urban landscape and wetland ecology.Therefore,the overall design of aquatic plants is one of the key factors related to the stable operation of the ecosystem of the constructed wetland park,and the special ecological design of aquatic plants is an essential part.In this paper,the design of the constructed wetland and aquatic plants was preliminarily defined through the literature research,and the research status and purification principle of the constructed wetland were summarized,and then the constructed wetland of Taizhou Bay was investigated for one year.Based on the continuous field survey of water pollution monitoring and aquatic plant species in Taizhou Bay since 2022,this paper analyzes the survey results combined with the long-term monitoring data of water quality.Evaluate the water quality of Jiaojiang River Basin,identify the pollution sources in Taizhou city;analyze the variation rules of nutrient salt concentration of river section in wet season,flat lake and dry season;investigate the spatial and temporal characteristics of water quality of river section in Taizhou Bay New Area;conduct the field survey of aquatic plant species and community structure in Taizhou Bay constructed wetland;investigate the geographical composition of aquatic plants and aquatic plant diversity;and analyze the influence of water environment on aquatic plant community structure of constructed wetland in Taizhou Bay New Area.The main study results are presented as follows:(1)Taizhou industrial source pollution emission showed a fluctuating growth trend in 2008.The lower reaches of the Jiaojiang River basin is greatly affected by domestic sewage,which is more likely to cause total phosphorus and organic pollution in the water body.The increase of agricultural non-point source pollution year by year and the expansion of breeding scale increase the excretion of livestock and poultry manure,which brings serious hidden danger of water environment pollution.A large amount of organic and inorganic wastes produced in the production process of aquaculture pose a threat to the local water environment.The water environment of Taizhou is not optimistic.All 18 connecting sections controlled by the province meet the functional requirements of the water area,accounting for 72.0% of the number of sections;other connecting sections cannot meet the functional requirements,accounting for 28.0%.3 class V water sections,accounting for 12.0%;3inferior class V water sections,accounting for 12.0%.River eutrophication exists in Taizhou Bay New Area,and the water pollution in the dry season is more serious than that in the wet season.In terms of time,the pollution is more serious in the dry season,and the permanganate index is more different in one year.In space,the average total phosphorus concentration of the suburban junction river,namely Shifang Temple,is the lowest among the 5 street section categories,but the overall trend of the suburban river> the suburban junction river> the urban river is presented.(2)Among the aquatic plants investigated in this study,28 species belong to 18 families and 23 genera.Among them,there are 25 families,20 genera and 25 species of seed phylum(Spermatophyta)and angiosperms(Angiospermae),17 families and13 genera of monocots(Monocotyledons),7 genera of 7 families(Dicotyledons),1genus of ferns(Pteridophyta),1 family,1 genus and 1 species of bryophytes(Bryophyta).It indicates that the biodiversity of Taizhou Bay constructed wetland is lacking.In terms of life type,the aquatic plants of Taizhou Bay constructed wetland include submerged plants,submerged plants,floating leaf plants,floating plants and wet plants,among which the species of submerged plants and wet plants are the largest,9 and 10 species respectively,but the application frequency of submerged plants is very few.There are 11 aquatic plants in the world,accounting for 47.83% of the total number of wetlands,10.58% of the total number of aquatic plants in China,including 11 species of aquatic plants,accounting for 39.29% of the total number of wetlands.The distribution of temperate components and tropical components in Taizhou Bay constructed wetland Park is uneven.The results show that the distribution of aquatic plants in Taizhou Bay constructed wetland Park is not widespread,and the aquatic plants are mainly distributed in the world.(3)combined with Taizhou bay district aquatic plant research and theoretical research results,summarizes the artificial wetland aquatic plant ecological design design target,accord with the Taizhou bay district of artificial wetland plant design,aquatic plant ecological strategy should conform to the principle of combination collocation,system structures,landscape configuration,space configuration principle,the principle of ecological security.Optimization strategies of constructed wetlands and spatial configuration patterns of aquatic plants.The technical route of aquatic plant design in Taizhou Bay constructed wetland was optimized from the two aspects of nutrient removal and the excavation of native species.