Assessing Aquatic Ecological Health for Lake Poyang, China: Part II Index Application

Abstract

As one of the largest Yangtze river-connected lakes in China, Lake Poyang's heath status has increasingly become a cause for concern. This study evaluated Lake Poyang's heath status using a newly developed index (ecosystem health index for Lake Poyang, LP-EHI). The evaluation results revealed a declining tendency in the lake's health status from 2010 to 2014. The health conditions for Lake Poyang were "good", "fair", and "fair" in 2010, 2013, and 2014, respectively. The individual indices for water quality, nutrient conditions, and benthic macroinvertebrate showed a deteriorating trend from 2010 to 2014 mainly due to human activities, such as industrial pollution. Further analysis revealed that the health status of Lake Poyang was strongly affected by hydrological processes. This study demonstrated the potential of LP-EHI in evaluating the ecological health of Lake Poyang. Such a heath status evaluation can be applied to other lakes, and can benefit lake management, restoration, and conservation.

Aquatic Ecosystem Health Assessment of Poyang Lake through Extension Evaluation Method

“…The study findings were in line with the conclusions summarized in previous studies [11,12]. The health status of Lake Poyang in the last few years has been 'moderate' or 'good' (Figure 3).…”

“…These indicators further manifested the aquatic ecosystem status in the lake but were not thoroughly considered in the published studies. The temporal and spatial variations in aquatic ecosystem health assessment of Lake Poyang were relatively consistent with previous research based on different indicators [11,12]. Our study considered biological elements and supporting physicochemical and hydromorphological elements and determined indicators thresholds.…”

“…A complete set of indicators could provide a more comprehensive illustration on the health status of the aquatic ecosystem than single-species indicators [10]. CB/DB, LWLa-D and MWLa-R were appropriate and special for this study compared with the indicators in previous studies [11,12]. Several ecological indicators have been proposed to quantify the development status of aquatic ecosystems [7,38].…”

“…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 Poyang [11,12]. The structure and function of a lake ecosystem are greatly controlled by its hydrology, geology, land cover, and climate characteristics, but assessing its actual health status is quite difficult; thus, the relative ecosystem health status has been evaluated in some lake ecosystems, including Lake Chaohu [8] and Baiyangdian Lake [9].…”

Assessing Aquatic Ecological Health for Lake Poyang, China: Part I Index Development

“…Additionally, for the goal of assessing the current health status of the largest freshwater lake, Lake Poyang, more indicators have better reflected its characteristics, like changeable water level, pathogenic potential, and dish-shaped sub-lake areas under management have been taken into consideration (Table 2). Undoubtedly, the comprehensive index can bring significantly higher confidence to master the health status from a global perspective and it works well as demonstrated in Part II [23]. However, it also lead to a huge data demand, increasing the difficulties to make comparisons of ecosystem health status among different lakes based on LP-EHI.…”