Research on the structure and characteristics of Chongming Island adjacent waters ecosystem based on Rpath
Based on the comprehensive fishery survey in the Chongming Island adjacent waters in November 2020,January 2021,April 2021,and August 2021,we used an open-source program Rpath to build a mass balance model containing 22 functional groups for this area.The ecosystem structure and characteristics in this sea area were then studied.Results showed that the trophic level for these 18 functional groups ranged from 1 to 4.32,with the highest trophic level of bottom carnivorous fish.The ecological transfer efficiency of small benthic organisms is the lowest(0.01),suggesting a bottleneck in their energy transfer to higher trophic levels and indicated it was the bottleneck to limit the energy transfer in the benthic food chain.The analysis of the overall characteristics of the ecosystem shows that the total system throughput of the Chongming Island adjacent waters ecosystem was 2 909.42 t/(km2·a),which was lower than that of the nearby marine ecosystem.Phytoplankton contributes 60%of the energy to the total primary productivity of the ecosystem and was the main nutrient source of this ecosystem.The total primary produc-tion/total respiration is 1.99 and the system omnivorous index is 0.18.This indicate that the Chongming Island adja-cent waters ecosystem has low maturity,simple trophic interaction,and low recovery ability after disturbance.Sens-itivity analysis showed that functional group biomass was the main index that affected the accuracy of ecosystem model output.The results of this study can provide a reference for the evaluation of the effect of the Changjiang River fishing ban.
Chongming Island adjacent watersmass balance modelRpathecosystem characteristics