Effects of abiotic factors on ecosystem health of Taihu Lake, China based on eco-exergy theory

Abstract

A lake ecosystem is continuously exposed to environmental stressors with non-linear interrelationships between abiotic factors and aquatic organisms. Ecosystem health depicts the capacity of system to respond to external perturbations and still maintain structure and function. In this study, we explored the effects of abiotic factors on ecosystem health of Taihu Lake in 2013, China from a system-level perspective. Spatiotemporal heterogeneities of eco-exergy and specific eco-exergy served as thermodynamic indicators to represent ecosystem health in the lake. The results showed the plankton community appeared more energetic in May, and relatively healthy in Gonghu Bay with both higher eco-exergy and specific eco-exergy; a eutrophic state was likely discovered in Zhushan Bay with higher eco-exergy but lower specific eco-exergy. Gradient Boosting Machine (GBM) approach was used to explain the non-linear relationships between two indicators and abiotic factors. This analysis revealed water temperature, inorganic nutrients, and total suspended solids greatly contributed to the two indicators that increased. However, pH rise driven by inorganic carbon played an important role in undermining ecosystem health, particularly when pH was higher than 8.2. This implies that climate change with rising CO2 concentrations has the potential to aggravate eutrophication in Taihu Lake where high nutrient loads are maintained.

Diversity of Entomophatogenic Fungi from Gunung Tukung Gede Nature Reserve

“…The difference in the diversity of entomopathogen mushrooms in these three types of habitats is closely related to abiotic factors. According to Wang et al, (2017), organisms and their abiotic environment are closely related and affect each other. In this case, the growth of entomopathogen mushrooms depends on the temperature of the environment, so entomopathogen mushrooms must be in the appropriate environment.…”

Spatiotemporal Patterns and Threshold of Chlorophyll-a in Lake Taihu Based on Microcystins

“…1). The shallow lake has a large surface area of approximately 2338 km 2 and average depth of 1.9 m (Wang et al, 2017). As the third largest freshwater lake in China, it serves as an important resource for drinking water and provides various ecosystem services such as agriculture, aquaculture, tourism, and navigation.…”

“…As the third largest freshwater lake in China, it serves as an important resource for drinking water and provides various ecosystem services such as agriculture, aquaculture, tourism, and navigation. It also receives considerable point-source and non-point source pollution from the surrounding watershed making the sharply increased load of pollutants such as nutrients and heavy metals during the 1980 s, which caused a rapid water quality deterioration and frequent occurrence of algal blooms since the 1990s (Sakai et al, 2013;Wang et al, 2017). At present, the lake still remains at a eutrophic state.…”

“…In general, four distinct seasons: spring (March, April, May), summer (June, July, August), fall (September, October, November) and winter (December, January, February) are divided of a year of Taihu Lake basin (Wang et al, 2017). Samples were collected from May to October (summer and autumn), December (winter) in 2013 and March (Spring) in 2014 from 25 locations across the lake (Fig.…”

“…Lake Taihu, the third largest freshwater lake in China, is an important source of drinking water for Wuxi, Suzhou and Shanghai, etc. (Wang et al, 2017). However, Lake Taihu suffered from severe nutrient over-enrichment over the past several decades (Qin et al, 2010).…”