Assessing the carrying capacity of Perinereis aibuhitensis in a Chinese estuarine wetland using a GIS-based habitat suitability index model

Abstract

Increasing attention is being paid to estuarine benthic community conservation and restoration globally. In this study, a GIS-based habitat suitability index (HSI) model was utilized to estimate Perinereis aibuhitensis (Grube, 1878) carrying capacity in estuarine wetlands of the Zhimai River, eastern China. Eight parameters were investigated, including sand content, salinity, pH, and petroleum hydrocarbon. Each parameter was investigated by a non-linear suitability function for transition from transformed parameter values into a normalized quality index. The weight of each parameter factor was determined by an analytic hierarchy process. A functional relationship was established between habitat suitability and population abundance to assess the carrying capacity. Twelve observation stations, divided into central, eastern, and western regions, were selected to collect data on biogeochemical and environmental parameters. These data were interpolated by GIS. The HSI model was then applied to obtain thematic maps of suitable habitat areas for P. aibuhitensis and corresponding carrying capacities. Results showed that central and western regions (approximately 1.013 km2, accounting for 66.38% of the total area) had a relatively high carrying capacity (130-150 ind. m-2), whereas the carrying capacity of the eastern region was below average. The abundance of P. aibuhitensis did not reach the carrying capacity of the environment under present conditions, especially in the eastern region. Results of the present study indicate that the execution of P. aibuhitensis restoration is feasible in this region; the areas around Stn 7 and in the eastern region are recommended for restoration.