Ecological Characteristics of Macrobenthos at the Yellow River Estuary in Summer

Abstract:

Based on the survey data at the Yellow River estuary in June 2012, the characteristics of macrobenthos were analyzed using canonical correspondence analysis and other methods. Sixty-seven species of macrobenthos were identified, which belonged to 6 phylums and 53 families. Among them, 28 species were crustacea; 17 were arthropods; 16 were mollusca; 3 were echinodermata; 3 belonged to other benthic groups. There were three dominant species including Leucon sp., Heteromastus filiforms and Glycinde gurjanovae. The average biomass and the habitat density were 2.03 g/m2 and 358 ind./m2, respectively. The ranges of Margalef species richness index, Shannon-Wiener diversity index and Pielou’s evenness index were 0.775–4.052, 1.825–3.976, and 0.637–0.924, respectively. The results of MDS and CCA indicated that 18 stations could be divided into three groups. The community of GroupⅠ(C4, D4) was composed of Apseudes sp.-Ophiophragmus japonicus-Gammaridea sp., and their distribution were positively correlated with the water depth, water temperature and salinity. Group Ⅲ(C1, B1) had H. filiforms-Notomastus latericeus, of which the distribution were positively correlated with ammonia, nitrate, total nitrogen and dissolved oxygen. GroupⅡincluded all other stations, and it had G. gurjanovae-Moerella jedoensis-Leucon sp., and their distribution had no obvious relationship with environmental factors. ABC curving analysis showed that the macrobenthic community tend to be disturbed moderately. The depth and ammonia were the most and second most relevant factors in the distribution of abundance.