Ecosystem Health Assessment of Baiyangdian Lake Based on Thermodynamic Indicators

摘要

The method of ecosystem health assessment (EHA) based on an index system using thermodynamic indicators has been applied to assess the state of health of Baiyangdian Lake. Indicators consisting of eco-exergy, structural eco-exergy, ratio of zooplankton biomass to phytoplankton biomass, and phytoplankton biomass were selected for the ecosystem health characterization. The assessment principle has been modified based on the typical characteristics of current ecological conditions for water areas in Baiyangdian Lake. The results of the health assessment indicate that water areas in sites 4 and 14 are in relatively good health, while the states of health of other water areas are deteriorated to varying degrees. By comparing the values of the ratio of zooplankton biomass to phytoplankton biomass and structural eco-exergy, the order of relative states of health from good to bad has been determined as: water area in the northeast and southeast (A) > water area in the north (D) > water area in the central and south (C) > water area in the west (B). Furthermore, based on the distribution of human disturbances in the water areas, for proposed regulating measures to improve the health of the impaired water areas we focus mainly on decreasing the nutrient loadings in water areas B and C and the submerged plant management of water area D.