Tác động của hồ chứa lưu vực Mê Công đến tích nước của hồ Tonle Sap cuối mùa mưa - đầu mùa khô
Abstract
The upper Mekong reservoirs have had many impacts on the basin, especially changing the hydrological and hydraulic regime, including Tonle Sap Lake (TLS) in Cambodia. The assessment of the impact on TLS lake also has many aspects of concern, including the decrease in the lake volume.
Our research, presented below, focuses on detecting the impact of flood cutoff on changes in the volume of TLS lake, especially in the late rainy season and early dry season. Through the study using mathematical model (MHT), the study evaluated the reduction in volume of TLS lake under 3 scenarios (1) No flood cut; (2) Cut flood 34 billion m3, (3) Cut flood 45 billion m3 corresponding to 3 groups of years with high, medium and low water, using hydrological years in the period 2011-2019.
The results showed that, with flood cutoff levels of 34 and 45 billion m3 of upstream reservoirs, the volume of TLS lake (compared with no cut) was reduced during the dry season (December 31) and varied according to the hydrological year: for the group of high water, the corresponding lake volume decrease is about 6-8.5%; 10-14% in medium flow years, and 15-20% in low flow years. This result has created a great advantage in assessing the water supply capacity of the lake in the dry season for both the Mekong Delta in general and the Mekong Delta in particular.
