Aquatic Ecosystem Health Assessment of Poyang Lake through Extension Evaluation Method

Yanhui Zhang,Rongrong Wan,Bing Li,Hongyun Zhu,Guishan Yang

doi:10.3390/w13020211

Abstract

Freshwater lakes encounter a series of problems, such as a decline in lake water quality, a sharp decrease in biodiversity, and ecological degradation. As such, lacustrine studies by highly skilled professionals and managers with water resources at home and abroad have focused on assessing the aquatic ecosystem health status of lakes. In this study, the health status of the aquatic ecosystem in the largest freshwater lake in China (Poyang Lake) was assessed, and its temporal and spatial characteristics were illustrated. The index contained three element layers, including hydrologic characteristics, trophic status, and aquatic organisms. The health status of the aquatic ecosystem was classified into three categories: ‘good’, ‘moderate’ (subhealthy), and ‘bad’. It was examined through extension evaluation method. Results showed ‘moderate’ health status, whereas remarkable seasonal and spatially variations. The annual changes in the health status were remarkably due to the influence of complex hydrological and hydrodynamic conditions. This study provides an overall understanding of the aquatic ecosystem evaluation in Poyang Lake. Such an understanding is vital for environmental conservation and identification of causes of the aquatic ecosystem degradation in Poyang Lake.

Highlights

Lakes, one of the aquatic ecosystems, are critical elements of Earth’s dynamic processes and essential to human economies and health [1]
This study provided a theoretical foundation for understanding the status of the aquatic ecosystem in Poyang Lake and identifying the causes of its health degeneration, which is crucial for ecosystem health management in this lake
Nutrient loadings should be reduced and eutrophication should be controlled to improve the health of the aquatic ecosystem in Poyang Lake

Summary

Introduction

One of the aquatic ecosystems, are critical elements of Earth’s dynamic processes and essential to human economies and health [1]. Because of human activities (e.g., increased pollution) and climate change, freshwater lakes have encountered a series of problems, such as decline of lake water quality and remarkable reduction in biodiversity and ecological degradation in recent years [2] Such ecological deterioration poses a threat to the use of water resources, drinking water supply and economic development [3,4]. The lake aquatic ecosystem health evaluation has been a focus of lacustrine studies among domestic and overseas researchers and water resource managers [5,6,7]. Since the 1980s, the health status of lake aquatic ecosystems have been explored through lacustrine studies by highly skilled professionals and managers with water resources at home and abroad. Several attempts have been made to assess them, such as in studies of Lake Chaohu [8], Baiyangdian Lake [9], Lake Erie [10], and Lake

Objectives

Methods

Results

Discussion

Conclusion