Functional Groups Of Macrozoobenthos In The Intertidal Flat Of Jiaozhou Bay

The intertidal flat of Jiaozhou Bay plays an important role in the ecological functions of thewhole ecosystem., and it also has great value for aquaculture economy as an importantbasement of shellfish in the northern China. The temporal and spatial variations of themacrobenthic communities were investigated in this study to explore the distribution of thefunctional groups of macrozoobenthos in the intertidal flat, which would provide the basedate for the study of Jiaozhou Bay. Further, the relationships between macrozoobenthos andthe environmental characters of the intertidal flat are also studied, with the aim of supportingthe protection and restoration in this religion.Based on the data collected from the macrozoobenthos survey conducted in the intertidalflat of northwestern Jiaozhou Bay in February, May, August and November2009, whichselected high tidal zone(A), low tidal zone(E), middle tidal zone (B、C、D), the functionalgroups of macrozoobenthos were studied. A total of71species was found in this investigation.Most of them were mollusks (31species), polychaetes (20species) and crustaceans (14species). The numbers of species in tidal zones A-E were26,33,35,38and31, respectively.According to their food preferences, the macrozoobenthos were classified into4functionalgroups, including planktophagous group (P1), carnivorous group (C), omnivorous group (O)and detritivorous group (D). The order of the compositional percentages of each functionalgroup in the total number of species of macrozoobenthos, from high to low values,wasfunctional groups C, Pl, D and O. The order of species diversity index of functional groupsfrom high to low values was C, D, Pl and O. The species richness index, evenness index andspecies diversity index were generally higher in middle tidal zone, lower in high and low tidalzone. The present results showed that the distribution of macrozoobenthic functional groupsvaried with the intertidal zone environment, and consequently was synthetical reflections oftheir habitat conditions.Fixed site sampling surveys were conducted in the intertidal flat of northwestern Jiaozhoubay from February2009to January2010. Seven sections were surveyed in February, May, August and November2009, and three sections were investigated in other months. Based onthe data of the seasonal investigation, the spatial and temporal distribution pattrens ofmacrozoobenthos functional groups was studied, and the composition contribution offunctional groups was analyzed by stepwise regression analysis. The order of the percentagesof the abundance and biomass of each functional group in the total abundance and biomass ofmacrozoobenthos was functional groups Pl, D, C and O, from high to low. The abundanceand biomass of most functional groups reached maximum in summer except Pl. Theabundance and biomass of all functional groups were higher in middle tidal zone, and lowerin high tidal zone. The functional group Pl was the greatest contributor in the totalcomposition of macrozoobenthos. According to the non-seasonal investigation, the totalbiomass of all functional group generally increased from high tidal zone to low tidal zone.The distribution of macrozoobenthic functional groups varied with the intertidal zoneenvironment, and consequently was synthetical reflections of their habitat conditions. Thefunctional group Pl was the most important functional group in this area.