Research On Annual Changes And Relationship Between Micro Biological Communityand Environmental Factors In Longfeng Wetland Reserve

Longfeng Wetland is located in the urban areas of Daqing,which is only 8 km away from center of the city, plays an important role in flood storage and regulation, water conservation and ecotourism.The investigation of the correlation between microbial community structure and environmental factors, can provide a biological way in monitoring and evaluating the structure and function of wetland ecosystem,and provide references for wetland management and protection.The study started from May 2014 to October 2015. We collected water samples and micro-biological community samples from 6 sampling plot in low water season and high water season, micro-biological species and physical and chemical factors were classified or determined.Water health of Longfeng wetland is evaluated by analyzing seasonal changes of micro-biological community structure and diversity index, and the method of multivariate statistical was used to find the correlation between environmental factors and micro-biological community structure.This research was carried out a total number of 182 species, which is belonging to48 species of rotifer,119 species of algae and 15 species of protozoa. Total abundance of rotifer is from 605.38 ind/L to 3858.01 ind/L during low water season, total abundance of rotifer during high water season is 5811.00 ~ 24835.27 ind/L.During low water season, species number of rotifer is 10~24, during high water season species number of rotifer is 55~84. Total abundance of algae is from 1.24×105 ind/L to 1.56×106 ind/L during low water season, total abundance of rotifer during high water season is1.39×105~2.1×106.During low water season, species number of algae is 55~84,during high water season species number of rotifer is 57 ~ 84. Total abundance of protozoa is from 935.32 ind/L to 27546.16 ind/L in low water season, total abundance of protozoa during high water season is 2203.35~17266.75 ind/L.During low water season, species number of algae is 9~10, during high water season species number of rotifer is 4~7.Annual changes of p H in samling plots varies from 7.84 to 8.13,conductivity value varies from 2.81μS/cm to 1704.00μS/cm,dissolved oxygen value is 2.80 ~ 7.61mg/L.Ammonia nitrogen value is 1.41~4.26 mg/L.Total nitrogen value is 2.23~9.77mg/L.Total phosphorus value is 0.63~2.85mg/L.Chemical Oxygen Demand value is59.60 ~ 91.49 mg/L.Comparing with basic standard limits of surface water aquatic environment,sampling plots in Longfeng wetland is below class V. According to the results of CLUSTER and MDS, sampling plots are separated into 2 groups.Number of rotifer dominant species is 27,while number of algae dominant species is 29 and number of protozoa dominant species potoz is 13.According to the abundance of rotifers,Shannon-Wiener diversity index is 0.76 ~ 2.56,Simpson diversity index is0.29 ~ 0.9.According to the abundance of algae, Shannon-Wiener diversity index is1.37~ 3.13,Simpson diversity index is 0.49~0.93. According to the abundance of protozoa, Shannon-Wiener diversity index is 0.17 ~ 1.41,Simpson diversity index is0.07~0.62.The results, which is examined by RDA analysis,show that water temperature and dissolved oxygen has a larger influence on micro biological community structure.Correlation analysis between environmental factors and diversity index shows that:Simpson diversity index of rotifer community is negatively and significantly correlated with total nitrogen, Shannon-Wiener diversity index of rotifer community is negatively and significantly correlated with total nitrogen, total phosphorus and conductivity. Simpson diversity index and Shannon-Wiener diversity of algae is significantly correlationed with water temperature. Simpson diversity index and Shannon-Wiener diversity of protozoa is significantly correlationed with dissolved oxygen.