The Research On Macrobenthos Community Structure And Diversity In Yanpu Bay Of Cangnan County

Based on survey data about sediments in Sep, 2014(autumn) and the date about intertidal macrobenthos in Oct, 2014(autumn) and Mar, 2015. The experiment was aimed to discover the influence of marcobenthos and heavy metals on human activities by using ABC curves, hierarchical clustering and MDS?ANOSIM?SIMPER. The main findings are as follows:There were 44 species belonging to 5 classes, 10 orders, 23 families and 31 genera in 5 intertidal zones of Yanpu Bay. According to the date, in the autumn 39 species belong to 5 classes, 9 orders and 21 families 29 genera;in the spring a total of 20 species belong to 5 classes, seven orders and 15 families and 17 genera. Abundance and biomass in autumn were greater and richer than in spring. The dominant species in autumn were Macrophthalmus japonicus, Metaplax longipes and Sinonovacula constricta, the dominant species in spring were Macrophthalmus japonicus, Metaplax longipes. Among the highest Importance Index is Metaplax longipes which is 4548. The Shannon-Wiener(H?) index was in the range of 1.3~2.50 in the two seasons,The Pielou J' index was in the range of 0.57~0.87, The Margalef abundance index was in the range of 1.59 to 4.25. The macrobenthic community structure was seriously damaged through analying ABC curve date. This result may be related to Bay shellfish farming which is use to using pesticides to kill inside and outside "enemies benthos" pollution, aquaculture pollution surrounding sea environmental degradation,over-harvesting and other human disturbance.The standard index of oils, As, Cu, Zn, Cr, CD, Pb, Hg and organic carbon in the intertidal zone are all less than 1, which meet the requirements of the environmental protection of the marine functional area. By the single factor index method and the comprehensive pollution index method, the results showed that the sediment in this area was in the pollution middle level. The sediment potential risk index shows that the region belongs to a low potential ecological risk level.Five types of functional groups were divided through the criteria for the classification of macrobenthic. There were 9 species belonging the P1 functional groups from 44 macrobenthos in intertidal zone of Yanpu Bay, which accounting for 20% of total. 17 species belonging to Ph functional groups accounted for 39% of the total. 10 species belonging to Ca. 6 species belonging to OM functional groups accounted for 14%. 2 species belonging to Ph functional groups accounted for 5% of the total % of the total.Ph functional groups were the dominant groups in A, B, C, D, E section of the benthic animal, the number of species Pl was the highest number of species. The A fracture surface in Shannon-Wiener(H?) indices were in the order of Ph> Om> Ca> Pl, J' indices were in the order of Pl > Om> Ca> Ph, D indices were Ph> Om> Pl> Ca; B section in H' indices were Ca> Om> Ph> Pl, J' indices were Ca> Om> Pl> Ph, D indices were Ph > Ca> Pl> Om; C section in H 'indices were in the order of Ph> Ca> Om> Pl, J' indices were in the order of Ca> Om> Ph> Pl, D indices were Om> Ca> Ph> Pl; D section in H' indices were Ph> Pl> Om> Ca, J' indices were Om> Pl> Ph> Ca, D indices were Ph> Ca> Pl> Om; E section in H' indices were Ph> Ca> Pl> Om> De, J' indices were Ca> De> Ph> Pl > Om, D indices were Ca> Ph> Om> Pl> De, and there were no De functional groups in A, B, C, D sections.In summary,the community structure of the intertidal zone in Yanpu Bay was disturbed by human being seriously.Macrobenthic functional group composition and distribution are related to the raising habits in high intertidal zone and middle intertidal zone in Yanpu Bay which are used to using pesticides to kill natural enemy benthic. But in low intertidal zone, laver farming is the main point which does not need to use pesticide, Macrobenthos are away from the harm and enhance environmental quality, ecological environment has great gradient; spring survey are operated in March, and the autumn investigation is in October,in the spring survey, the air and water temperature are low, main distribution of Macrobenthos is in the deep water area, but in autumn survey, temperature are higher, the main distribution of Macrobenthos are in the shallow water area.