Research On Characteristics Of The Phytoplankton Community And Environmental Effect In Zhalong Wetland

Our country has numerous natural wetlands in cold areas. It is characterizedby winter long while cold, summer short but warm, the low annual averagetemperature, the large annual temperature difference. It is important for improvingthe ecosystem protection and keeping sustainable development to research on coldregions natural wetland. For the characteristics of cold regions to the Zhalongwetland example, a systematic study was carried on spatial and temporalcharacteristics of phytoplankton community populations. Using multivariatestatistical methods, Zhalong wetland environmental factors were resolved.Community ecology statistical methods was applied to the dynamic relationshipstudy between environmental factors and phytoplankton community structure.Based on biological, physical and chemical indicators coupled, Zhalong wetlandsnutrition status was evalued while Zhalong wetland water environment predictionmodel was set up. The purpose of this study was to reflect the characteristics of thephytoplankton community ecology fully, perfectly and systematicely in Zhalongwetlands, explore our cold regions phytoplankton community succession laws andthe relationship with environmental evolution, as well as provide basic informationin-depth study of long-term changes in phytoplankton of wetlands, wetlandecosystem dynamics change mechanism, bio-sustainable use of resources,ecological environment impact assessment, the formulation of the ecological andenvironmental protection measures.By Zhalong wetland monitoring and analysis of the integrity hydrologicalyear, comprehensive, systematic phytoplankton identification, species compositionand community structure was obtained in our studied regions. It had a wide varietyof complex phytoplankton composition in the Zhalong wetland.303phytoplanktontaxa were identified, belonging to8divisions,11classes,24orders,42families,93genera and303species. Phytoplankton abundance of Zhalong wetlandsoccurred temporal and spatial heterogeneity. The Zhalong Wetland phytoplanktonaverage abundance was409.52×10⁴ind. L^-1. Of them, Dryptophyta had thehighest abundance with287.70×10⁴ind. L^-1and70.25%of the total abundance,Chrysophyta followed,39.66×10⁴ind. L^-1, accounting for9.68%, diatoms ranked3to23.09×10⁴ind. L^-1,5.64%of the total abundance; followed by Cyanophyta17.15×10⁴ind. L^-1（4.19%）, Euglenophyta14.54×10⁴ind. L^-1（3.55%）, theChlorophyta12.34×10⁴ind. L^-1（3.01%）, Dinophyta11.49×10⁴ind. L^-1（2.80%）,minimum Xanthophyta, only3.55×10⁴ind. L^-1（0.87%）. It occurredphytoplankton abundance temporal and spatial heterogeneity in Zhalong wetlands.Based on similarity coefficient, cluster analysis and multidimensional scale analysis （MDS） was carried on, water sampling points according on thephytoplankton community structure were divided into four, five, five groups.On the basis of traditional systematics of phytoplankton community, combinedwith the theory of community statistical analysis, we explored the relationshipbetween Zhalong wetlands phytoplankton community structure and environment.It was found from principal component analysis （PCA） for different environmentalfactors of Zhalong wetland that it played a major role to phytoplanktonnonmetallic environmental factors to physical indicators, followed by organic,inorganic indicators in the poor water period and the medium water. Non-metallicion main ingredient were the physical and biotic factors in the rich water period.Metal factors played a major role in the distribution of species, respectively, forthe heavy metals and light metal in the poor water period and the rich water period.The light metal metal ions in the metal environmental changes were the mainfactor in the medium water. By detrend analysis，it was determined the gradient ofspecies data to choose canonical correspondence analysis method to study therelationship between Zhalong wetland phytoplankton community andenvironmental factors. We obtained prediction maps of3,9,6environmentalfactors in the poor, medium and rich water period in Zhalong wetland and it hadgood regression for water environment.The Zhalong Wetland phytoplankton abundance, diversity, dominantpopulation, indicated taxa, pollution indicator values, trophic state index methodwere carried out to explore Zhalong wetland water status, its temporal and spatialtrends. View from the phytoplankton abundance, all the water of the monitoringsites were eutrophic. View from phytoplankton diversity,4.11%in oligotrophic,32.88%in mesotrophic,65.75%in eutrophic. It was different in space and time forZhalong wetlands phytoplankton dominant species. Cyclotella meneghiniana,Cryptomonas erosa and Ankistrodesmus angustus were dominant throughout theyear and we can infer water quality was in the dirt for the whole year. As wasshown from indicator organisms and pollution indicator values, phytoplanktonspecies belonging to the dirt with α-and β-in dirt indicator species, and wasindicative of a higher price, and more dirt with less taxa. from the trophic stateindex, accounted for16.44%in mesotrophic, accounted for83.56%of eutrophic.Overall, the Zhalong wetlands was mainly eutrophic state and in the moderatelypolluted state of water body.