Evaluation of Environmental and Ecological Impacts of the Leading Large-Scale Reservoir on the Upper Reaches of the Yellow River

Jun Qiu,Tie-Jian Li,Fang-Fang Li

doi:10.3390/su11143818

Abstract

Large-scale reservoirs have played a significant role in meeting various water demands and socio-economic development, while they also lead to undeniable impacts on the environment and ecology. The Longyangxia reservoir located on the Yellow River is the first large-scale reservoir on the upper Yellow River with a control area of 18% of the entire Yellow River Basin. Since it was put into operation in 1987, it has made great contributions to the national economy for over 30 years. In this study, the socio-economic benefits of the Longyangxia reservoir in power generation, water supply, flood control, and ice prevention are investigated. More importantly, its impacts on the ecology and environment are also presented and analyzed, such as the impacts on river morphology, flow regimes, peak flow, fish, phytoplankton, and zooplankton. It can be concluded that the construction of the Longyangxia reservoir contributes greatly to socio-economic benefits, the water area nearby has formed a new ecological environment, and the trophic level of the aquatic environment has probably increased.

Highlights

Construction and operation of large-scale reservoirs capable of controlling certain areas of river basins can resolve contradictions in spatial and temporal distributions of water resources with the functions of flood control, power generation, irrigation, water supply, and navigation
The Longyangxia reservoir is located in the untraversed Qinghai–Tibet Plateau, and the ecological environment is almost untouched
Feng [25] tested water samples in the Longyangxia reservoir in 2008, 20 years after the reservoir’s operation, and concluded that the water quality met the standard of grade II according to the “Environmental quality standards for surface water”, which means that it can be used in the first-level protection area of surface water sources for centralized domestic and drinking water, in the habitat of rare aquatic organisms, in the spawning field for fish and shrimp, in the feed field for young fish, etc

Summary

Introduction

Construction and operation of large-scale reservoirs capable of controlling certain areas of river basins can resolve contradictions in spatial and temporal distributions of water resources with the functions of flood control, power generation, irrigation, water supply, and navigation. Altering the distribution of water resources results in changes to the hydrological characteristics of lower reaches [1,2,3] and, directly or indirectly affects the ecological environment. Studies [4] have shown that dams have been the main cause of nearly 20% of extinctions, threats, or endangerment of 9000 identifiable freshwater fishes worldwide in the past century. Semimigratory fish cannot reach spawning areas because of the dams [6,7]. Petts [9] classified the reservoir impacts on river ecosystems into different levels

Methods

Results

Conclusion