Study On Macrobenthic Animal And Assay Of Water Quality Of Nansi Lake

In recent years, the Nansi Lake ecological environment severely damagedcondition and needs of the north water pollution treatment, Shandong Province,accelerate the construction of water pollution control projects, water qualityimprovement. Macrobenthos of Nansi Lake were collected from April2012toNovember, and the number of species, changes in space and time of the dominantspecies, density and study the biomass of macrobenthos community structure anddiversity water quality in a preliminary study of macrobenthos correlation analysisand water pollution initially.Nansi Lake hydrological onditions and environmental characteristics of the studyin Nansi Lake laid a total of11sampling points, respectively, in the spring of2012(April), summer (June) and autumn (August) to the winter of2012(November)sampled of water4times. Sampling is divided into the collected two methods ofquantitative collection and qualitative. The quantitative acquisition, the qualitativecollect every kind of three parallel samples were collected.Mesh screen filter sortingwill be picked in the samples back to the lab, and then classify and identify statisticalquantities and determination of biomass; using species composition, density, biomassthe community spatial differences and time differences; use of biological diversityindex and similarity index of community diversity analysis; correlation analysis of theenvironmental factors and the number of three animal species density; using fourbiological index such as water monitoring water quality evaluation andShannon-wiener species diversity index, Pielou evenness index, the Margalef varietyindex, BPI-Biology Pollution Index the biological pollution index evaluate waterquality biologically.1、The survey were collected5108macrofauna,50species, belonging to four of20 families and41genera. There are three major categories: mollusks, aquaticoligochaetes, aquatic insects, molluscs20genera and23species, the aquaticoligochaeta7genera and10species of aquatic insects of10genera and13species, theother4genera and4species. Molluscs (mainly snails) the aquaticoligochaetes(mainly Limnodrilus), aquatic insects (mainly chironomid larvae)accounted for the proportion of the number of individuals were66.249%,23.3164%,10.239%; another were only0.196%. Mollusks are the most stable and the mostimportant groups.2、Analysis Nansi Lake sampling sites the number of the species, three types ofestuary less Fangzhuang River least number of species, only10kinds; Xinxue River15kinds; Zhuzhaoxin River17; species number of the rest of the sampling pointsmoreand the number of species or less, are more than20kinds Weishan Lake11sampling points number of species up to27kinds. Species mainly mollusks numberof species of aquatic insects, mollusks, aquatic oligochaeta class. Little change inspecies composition changes with the seasons.3、The Nansi Lake dominant species of one kind of grain marsh snails, the oak beansLo and Limnodrilus of case. Pattern marsh snails in9samples, more in of DushanLake and Weishan Lake more; the oak beans Lo the most widely distributed, in the11samples, Weishan Lake up in three entrances rarely are less than10; Limnodrilus casein9samples, but the difference in the number of individual samples in the theNanyang Lake largest number, accounting for45%of the total number of each speciesfor Zhuzhaoxin River, the Limnodrilus genus accounted for88%of the total numberof each species, and the other samples are in a small number.4、Time variation and spatial variations of the the Nansi Lake of macrobenthos densityand the biomass of the differences are great. Four seasons, the size of the three typesof animal density are mollusks> aquatic oligochaetes class> aquatic insects, the sizeof the biomass are mollusks> aquatic insects> aquatic oligochaetes class; Nansi Lakemacrobenthos in all seasons vary widely distributed at all sampling points, exceptsummer, spring, autumn, winter, aquatic insects, aquatic oligochaetes density are themost abundant Nanyang Lake, followed by Zhuzhaonew River, the8th sampling point density is large too; mollusks in addition to the spring, summer, autumn andwinter are Weishan Lake sampled the11th largest all seasons Followed by5,6,10sampling point density, the2,3,8,9sampling point density are very small. Distributionpattern and density of the biomass are the same roughly.5、There are some differences in the Nansi Lake of macrobenthos diversity indexvalues at each sampling point, the Zhuzhaonew River Shannon-wiener speciesdiversity index, Pielou evenness index is small, other sampling points is larger andless. Margalef species richness index was the smallest in the Fangzhuang new River,Xinxue River, the largest,3-9sampling points in turn increases the number ofsampling points10,11, slightly less than the sampling points7,8,9. The Pielou indexcompared to the seasonal changes in the other two indices, Shannon-wiener speciesdiversity index, the Margalef species richness index variation for each sampling pointare different. Each sampling point community is similarity coefficient. Analysis ofmacrobenthos and water quality of physical and chemical factors, aquatic insects andmollusks number of species and density presented negative correlation, the number ofspecies of aquatic oligochaetes, density, and temperature was positively correlatedwith temperature. Density and dissolved oxygen for aquatic insects and aquaticoligonucleotide was negative correlation, aquatic insects and aquatic oligochaetesnumber of species and mollusks density and number of species and the dissolvedoxygen was positively correlated, especially molluscs and aquatic The oligochaetesand dissolved oxygen showed a significant positive correlation. Most of the threetypes of large benthic species number and density of TN, TP, CODMnnegativecorrelation, a few showed positive correlation, the correlation was not significant. Thenumber of species of aquatic oligochaetes with TN, TP, CODMnthree types ofindicators were tested significant correlational eutrophic water is conducive to thegrowth of aquatic oligochaetes, aquatic oligochaetes can indicate water contaminatedlevel.7、By measuring the water physicochemical indicators have access to the FangzhuangRiver water quality overall is in Ⅲ-Ⅴ class Xinxue River, Zhuzhaonew River waterquality overall are forⅡ-Ⅲ class, Lake District water quality in addition to Nanyang Lake TN evaluation for classⅤ, Other indicatorsthe evaluation Dushan Lake,Zhaoyang Lake Weishan Lake water quality areⅠ-Ⅲ classⅠ-Ⅱ class majority.Macrobenthos in biological index evaluation Fangzhuang River water quality areheavily pollution, the Zhuzhao new River water quality are middle pollution, othersampling points in addition to the Weishan Lake11sampling points for the other lightpollution are light pollution.