Uni-Bayreuth

Sprungmarken

 

Box model and numerical simulation of Bosten Lake, Xinjiang, China

Ning Li1, Kinzelbach Wolfgang, Wenpeng Li, Xinguang Dong
1 IfU, ETH

P 1.6 in Numerische Simulation von Strömungs- und Transportprozessen in Grundwasserleitern und angrenzenden Kompartimenten

Bosten Lake is located in the southeast of Yanqi Basin, an important agricultural area in Xinjiang, China. All rivers of Yanqi Basin flow from their headwaters to Bosten Lake. The outflow of the lake supports the downstream agricultural and natural environments. The intensive agricultural activities over last decades in the basin resulted in decreased lake levels and deteriorated lake water quality. In order to find solutions for the local water resources management, a two-box model is constructed to understand the development between 1958 and 2008. The two-box model of the lake indicates that the flow budget is easily closed and to achieve salt balance, the ratio of outflow concentration and average lake concentration is around 0.7. This is due to the short-circuiting between lake inflow and the pump stations abstracting water from the lake. This ratio is also supported by a 1D numerical flow and transport model of the lake calibrated with observations of lake level and lake concentrations.

 

As the lake acts as an integrator of what happens in the agricultural basin, the box model of the lake is sufficient to estimate what changes in upstream. Practices are needed to fulfil requirements for lake quality and lake outflow. Different measures in the basin are compared with respect to their improvement of lake water quantity and quality. Finally a scenario combining measures is suggested. The result shows that this combination of measures is sufficient to bring future lake TDS concentration well below the required 1000 mg/l. At the same time outflow is increased. The model results are subjected to an uncertainty analysis.

Letzte Änderung 25.10.2013