The Relationship Between Nutrient Changes And Microbial Communities In The Migratory Bird Habitat At The High Water Level Range

In recent years,with the continuous development of industrial technology,the population is more intensive.The discharge of pollutants and nutrients has a great impact on the lake environment.The proportion of various nutrients is an important factor limiting the growth of aquatic microorganism,and the influence of trophic gradient on microbial community structure is also crucial.Salinity is one of the main factors affecting bacterial community structure,and its influence even exceeds other factors such as temperature,pH and so on.Poyang Lake is the largest freshwater lake in China and the largest winter habitat for migratory birds.The main part of the Poyang Lake migratory bird reserve is located in Yongxiu County,Jiangxi province.The seasonal changes in the water level in the protected area are obvious.The study on Poyang Lake,the water quality of the lake and the base heavy gold,is more related to the research environment.Relatively smooth,the research objects are relatively in the mixing state,and the spatio-temporal variability is not significant.The migratory bird habitat is in a repeated agitation state due to the effects of the prey,disturbance and excretion of migratory birds,and the change in the transfer of the matter between water and water and the sediment is changed.The location of migratory birds located at the water and land boundary of Poyang Lake can help to further study the migration and change rule of nutrients in water and lake sediments.The influence of N and P on the abundance and diversity of microbial community structure,the relationship between the fluctuation of nutrient content and the variety of microbial community under the variation of water level,provides a reference for the study of the mechanism of microbial degradation and absorption of nutrient salts,and provides a reference for the effective prevention of water eutrophication.This experiment takes Poyang Lake migratory bird protection area?DaHu Lake and Sha Lake?as the research area.The nutrient and microbial communities in water environment were studied.To study the seasonal dynamic changes of nutrient salt and microbial community in water environment samples at the migratory bird habitat,and to study the relationship between the fluctuation of nutrient content and the change of microbial community population under the high water level variation.Sampling points were set up at the great lakes pond and Shahu water land junction,and water samples and soil samples were taken at irregular intervals.The nutrients in water environment samples were analyzed by different methods.The determination of TP,TN,NH₄⁺-H,nitrite and nitrate use molybdenum antimony spectrophotometry,alkaline potassium persulfate digestion ultraviolet spectrophotometry,nnhtel reagent spectrophotometricmethod,spectrophotometricmethodandultraviolet spectrophotometry.The determination of total microbes according to the total number of bacterial colonies;microbial diversity The bacterial diversity was analyzed by PCR-RFLP.In this experiment,the total DNA in the sample was extracted by 0.22 micron m microporous membrane.The PCR electrophoresis strip was recovered and DNA was purified.The purified DNA and PMD19-T carrier were carried out overnight.The carrier cells were constructed into the DH5-alpha carrier cells and the carrier cells were produced to make the bacterial liquid.The products were analyzed by RFLP type.Different clones were sequenced and identified.The seasonal variation of nutrient salts in water environment samples showed that TN,TP,ammonia nitrogen and phosphate had obvious correlation to the changes of total bacterial colonies.The correlation between the nutrient salt and the total number of colonies in different water periods was different,which was related to the multiple factors affecting the bacterial colonies.At a certain concentration and with positive correlation,the variation of TN,TP and NH₄⁺-H in the water period is low water period>flat water period>high water period,and seasonal concentration changes in winter>autumn>spring.There are many kinds of bacteria in the Great Lakes,including Proteobacteria,Proteobacteria,Proteobacteria and delta proteobacteria.There are 28 positive clones of alpha deformia,belonging to 7 families and 9 genera,accounting for 41.1%of the total proportion;beta deformia has 12 positive clones,belonging to 4 families and 6genera,accounting for 17.7%of the total proportion;gamma deformus has 8 clones,belonging to 5 families and 8 genera,accounting for the total proportion of 11.7%;delta strain has 5.The positive clones belonged to 2 families?genera?,accounting for7.3%of the total proportion,The 8 positive clones identified as actinomycetes were composed of 5 different genera,accounting for 11.7%of the total proportion,2positive clones belong to Saccharibacteria gate,2 positive clones belong to the phylum phylum,1 positive clones belong to cyanobacteria,1 positive clones belong to nitrifying spiral bacteria gate,and 2 positive clones may belong to the other two new species.