Abstract
Abstract Water level is considered as the key factor affecting the structure and function of lake ecosystems. The Mann-Kendall technique and range of variability approach (RVA) were used to quantitatively evaluate the hydrologic alteration due to Three Gorges Reservoir (TGR) in Dongting Lake. Results indicate the following. (1) The average annual water levels at Chenglingji station showed increasing trends (p < 0.05), while that at Nanzui station showed a decreasing trend (p < 0.05). The turning year occurred in 2003, which reflects the significant effects of the TGR on the water level regime. (2) The highly altered parameters were 1-, 3-, and 7-day minimum water levels both at Chenglingji and Yangliutan, and in October both at Nanzui and Yangliutan, with the degree of hydrologic alteration being larger than 80%. However, 1-, 3-, 7-, and 30-day maximum water levels at three stations had relatively small alteration, with the degree of hydrologic alteration being smaller than 41%. (3) The hydrologic alteration degrees at Chenglingji, Nanzui and Yangliutan station were all moderate, with changes of 50, 46 and 49%, respectively. (4) Water level regimes at Dongting Lake were mainly jointly affected by reservoir operation, land utilization change and river channelization. These changes in water level regimes have a negative impact on aquatic and terrestrial ecosystems. This study provides a scientific reference for the protection of lake ecosystems under hydrologic alteration.
Highlights
IntroductionLakes, providing numerous goods and services, are important for the development of human life, including water supply for
This study provides a scientific reference for the protection of lake ecosystems under hydrologic alteration
Based on a newly updated water level dataset, the variations of water level characters in Dongting Lake caused by the Three Gorges Reservoir (TGR) were evaluated with the range of variability approach (RVA) method
Summary
Lakes, providing numerous goods and services, are important for the development of human life, including water supply for. Dams and reservoirs can provide important sources of renewable energy, irrigation water and flood and drought control, and can help to improve the safety of water, but they have a remarkable impact on the ecological integrity of the aquatic system and the productivity of the downstream lake and wetland systems (Arthington et al ; Poff & Zimmerman ; Grill et al ). The quantitative assessment of water level variations due to the impoundment and operation of reservoirs is beneficial to protect the lake ecosystem
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
