Quantitative Estimation Models and Their Application of Ecological Water Use at a Basin Scale

Ecological water use (EWU) is urgent in need in the lower reaches of Tarim River in China. Estimation of water amount for EWU is depending on some parameters and modeling. EWU is mainly consists of two parts in no runoff area in the basin, i.e. total water amount for restoration groundwater table and total stand water amount of the all river courses. The former is including water amount for restoration of groundwater table, lateral discharge and evaporation of water surface. The estimated values are 8.18 × 108 m3, 0.68 × 108 m3/a and 0.132 × 108 m3/a respectively. Based on the groundwater depth rising 4.0 meters requiring 5 years, the total water amount for restoration groundwater table is 2.448 × 108 m3/a. The latter, i.e., total stand water amount is 1.992 × 108 m3/a. However, the development of water management measures could alleviate the issue and lead to sustainable EWU in the lower reaches of Tarim River.