Comparative Study On Plankton And Main Physical And Chemical Indexs Of Five Lakes

WuHan was known as the "hundred of Lake City". Lakes played an significant role in wuhan economic and social development. In order to thorough understanding lakes characteristics, especially the physico-chemical and biological properties in summer, to provide more detailed data and material for lake manage. The study on comparative of main ecological factor investigation of Liangzi lake, Futou lake, chaipo lake, Nanhu lake, and Yezhi lake in wuhan in 2007.Through the research,The results indicated that:1.Some of the physical and chemical index in lakes existed the statistically significant relational expression. Between TN and NO2--N, NO3--N, TP, PO43--P; TP and NO2--N,NO3--N, PO43--P; NO2--N and NO3--N, PO43--P; NO3--N and PO43--P; CODMn and TN, TP, NO2--N, NO3--N, PO43--P, were all linear relationship. NH4+-N had a power function relationship with TN, TP, CODMn, NH4+-N had the binomial relationship with TN, TP, CODMn,had no relation ship with PO43--P.2.There were 133 species of phytoplanktons in Five lakes. Wherein Cyanophyta (43), Chrysophyta(1), Xanthophyta(1), Bacillariophyta(28), Pyrroptata(6), Euglenophyta(12), Cryptophyta(2), Chlorophyta(40). There were 43 species of zooplankton. Wherein protozoa (14); rotifers (23); cladoceran (3); copepods (5). the species quantity of phytoplanktons of five lakes followed by Liangzi lake> Nanhu lake> chaipo lake> Futou lake> Yezhi lake; the species quantity of zooplankter followed by chaipo lake> Futou lake> Liangzi lake=Nanhu lake> Yezhi lake; the average density of phytoplanktons followed by Nanhu lake> Yezhi lake> Liangzi lake> chaipo lake> Futou lake; the average biomass followed by Liangzi lake>Nanhu lake>Futou lake> chaipo lake> Yezhi lake; the average density and average biomass of zooplankter followed by chaipo lake>Nanhu lake>Yezhi lake>Liangzi lake>Futou lake. The respective algae-type characteristics in Liangzi lake、Futou lake、chaipo lake、Nanhu lake and Yezhi lake are " Cyanophyta & Bacillariophyta", " Cyanophyta & Bacillariophyta & Chlorophyta" " Cyanophyta & Chlorophyta", " Cyanophyta & Bacillariophyta & Chlorophyta" " Cyanophyta & Chlorophyta". In addition, the determination result of plankton was compared analysis with Published historical data.3.The determination result on DOC, POC, and TOC in five lakes showed that:the mean of TOC content followed by Yezhi lake> Nanhu lake> Futou lake> chaipo lake> Liangzi lake; the mean of DOC content followed by Yezhi lake>Nanhu lake>Futou lake> chaipo lake> Liangzi lake; the mean of POC content followed by Nanhu lake> Yezhi lake>Futou lake>chaipo lake>Liangzi lake; DOC is the main part for TOC, the percentage followed by Yezhi lake> Liangzi lake> chaipo lake> Futou lake> Nanhu lake; the mean of DOC/POC followed by Yezhi lake> Liangzi lake> chaipo lake> Futou lake>Nanhu lake. The main factors which effected the change of DOC, POC, and TOC in lakes were Human activities, the entrance of outside organic matter and aquatic creatures growth and decomposition in lakes.4. The average contents of chlorophyll-a in five lakes followed by Nanhu lake>Yezhi lake>Chaipo lake>Futou lake>Liangzi lake. chlorophyll-a and TP, NO3--N, PO43--P, TP, CODMn, were correlative.5. Depending on the principal component analysis of Physical and chemical index in five lakes, the results showed that, Three principal component respectively for nutritional factors (TN, NO2--N, NO3--N, TP, PO43-P, and CODMn), survival factor(DO) and ammonium absorption factors(NH4+-N). The results showed that, after Q type clustering analysis, Five lakes could be divided into two categories, one include Futou lake and Liangzi lake,the other include Nanhu lake、Yezhi lake and Chaipo lake, This was caused by the city waste water、domestic sewage and aquacultural production.6.the principal component analysis and factor analysis of five lakes plankton showed that:the first principal component to impact of fivelake plankton was the number and weight of Copepoda and Cladocera; the second principal component was the weight and quantity for theRotifer and the number of Chlorophyta; the third principal component was the number and weight of Cryptophyta; the fourth principal components was the number and weight of the Protozoa; the fifth principal component factor was the number of Cyanophyta; the sixth principal component was the number of Bacillariophyta and the weight of Chlorophyta. According to the type and quantity of plankton and hierarchical clustering, the 13 points of five lakes could be divided into 5 categories.The formation of this result was due to urban wastewater, sewage and aquiculture.7. Some recommendations for the protection of lakes, including the improvement of lake management, implementation of appropriate breeding, control of sewage discharge, and the ecosystem governance of lake.