Ecological Characteristics of Macrobenthos Near Hengqin Island in Zhuhai

LUO Yan; LIN Lihua; ZHANG Cuiping; HUANG Huamei

Abstract：Based on the data from four macrobenthos surveys in November 2013,May 2014,February and August 2015 in the sea near Hengqin Island,Zhuhai,the composition,spatial and temporal distribution and diversity of macrobenthos species were analyzed.The results showed that a total of 210 macrobenthos species were identified in 9 phylum,including 58 species of Arthropoda,52 species of Mollusca,42 species of Annelida,40 species of Chordata,8 species of Echinodermata,6 species of Coelentera,2 species of Sipuncula,1 Species of Nemertea and 1 species of Echiura,with average of 30 individuals,45 in spring,17 in summer,12 in autumn and 44 in winter.The density of macrobenthos was ranged from 0 to 1490 ind/m2,with the average of 212 ind/m2 and the seasonal trend of winter＞spring ＞summer＞autumn.The biomass of macrobenthos was ranged from 0 to 288.5 g/m2,and 16.61 g/m2 in average,with the seasonal trend of spring＞winter＞ autumn＞summer.There were a total of 13 dominant species (dominance index＞ 0.02),which changed quickly in different seasons.The main dominant species were Cossurella dimorpha and Potamocorbula laevis in spring,Metapenaeus ensis and Turritella bacillum in summer,Cossurella dimorpha in autumn,Siliqua minima in winter.The Shannon-Wiener diversity index (H'),Pielou evenness index (J'),Diversity threshold (Dv) and Margalef richness index (D) were 2.49,0.78,1.96,and 1.87 respectively in spring,2.81,0.90,2.57,and 2.49 in summer,2.34,0.75,1.88,and 1.60 in autumn,2.71,0.81,2.32,and 2.80 in winter.The changing trend of these indexes was the same,higher in summer and winter,lower in spring and fall.Significantly negative correlations were between Margalef richness index and depth(P＜0.05)in spring,and between Shannon-Wiener diversity index and DO(P＜0.05) in autumn.The Margalef richness index was significantly positive correlated with pH (P＜0.05) in spring.There was no significant correlation among the Shannon-Wiener diversity index,Pielou evenness index,Margalef richness index and the environmental factors in summer and winter.