Aquatic Ecosystem Deterioration and Its Potential Drivers in a Floodplain Lake in the Lower Yellow River Area, North China

TL;DR

This study examines the decline of Lake Dongping's aquatic ecosystem over 40 years and identifies water quality, water levels, and human activities as key drivers.

Contribution

The study provides a 40-year analysis of aquatic vegetation changes and identifies specific drivers of ecosystem deterioration in a floodplain lake.

Findings

Aquatic vegetation diversity in Dongping Lake decreased from 40 to 6 species over 40 years.

Pollution-tolerant Potamogeton crispus became dominant around 2000, replacing original species.

Water quality, water levels, and human activities were identified as primary drivers of ecosystem degradation.

Abstract

Lake Dongping is a floodplain lake in the lower Yellow River area experiencing ecosystem deterioration. Understanding the structure and succession of its aquatic communities is essential for ecological restoration. However, due to lack of long‐term monitoring data, the onset and causes of ecosystem degradation in this lake are unclear. This study employed Landsat imagery and Support Vector Machine (SVM) to extract spring and summer aquatic vegetation distribution in Dongping Lake, combined with field survey data and environmental factors to analyze its succession over the past 40 years. Redundancy Analysis (RDA) was then used to investigate the factors driving aquatic ecosystem deterioration. Results indicate that since 1979, aquatic vegetation in Dongping Lake has generally declined, with species diversity decreasing from 40 to 6 species and community structure becoming increasingly simplified. Pollution‐sensitive vegetation has experienced substantial reductions in both distribution area and biomass. The period around 2000 marked a critical transition when pollution‐tolerant
Potamogeton crispus
emerged as a dominant monoculture while original dominant species continued to decline. Water quality and water levels were identified as primary drivers of aquatic vegetation succession, with poor water quality and high water levels being key factors in community degradation. Meteorological conditions also contributed to aquatic vegetation changes. Human activities including aquaculture and the South‐to‐North Water Diversion Project mainly influenced aquatic vegetation succession indirectly by altering water quality and water level conditions. Our results provide valuable insights for assessing ecosystem health and offer potential management strategies for future ecological restoration of Dongping Lake.

This study employed Landsat imagery and Support Vector Machine to extract spring and summer aquatic vegetation distribution in Dongping Lake, combined with field survey data and environmental factors to analyze its succession over the past 40 years. Redundancy Analysis was then used to investigate the factors driving aquatic ecosystem deterioration.

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