| 摘要: | Water resources of Mongolia are highly vulnerable to climatic conditions due to harsh climate with four distinctive seasons, high annual temperature fluctuations, and low rainfall. Average annual temperature range between 8.50C in the Gobi and -7.80C in high mountain region and average annual precipitation is 200-500 mm and total water resource of estimated at 599 km3, 63.5 % is surface water and 36.5 % is actually groundwater. Therefore, water withdrawals are 550 km3. Recently, mining is rapidly changing the water consumption and energy landscape and in 2010, mining just consumed 13% and the demand for water is projected to increase fivefold from 2012-2030. So, in the future the water resources are very lacking for mining projects, and will be impossible to obtain water from underground. One of the possible solution is Rainwater Harvesting (RWH), to collect rainfall or snows. Objective of this study is to determine the possibility of rainwater harvesting system in Kherlen river basin, East Mongolia. The precipitation, air temperature and water levels of three different hydrological station in Kherlen river basin, obtained by the Institute of Meteorology and Hydrology (IMN), from 2000 to 2015. The results show that annual total precipitation ranges from 150-400 mm. About 90 % of annual precipitation falls only in the warmer season. The lowest precipitation falls in winter and the highest one occurs in July. The average 1year temperature of Mungunmorit station is -2.8±0.80C, Undurkhaan station’s 0.2±10C and Choibalsan 1.7±10C. The water level of river, at river upstream is lowest, then increases at middle and downstream. The average river water level at Mungunmorit station is 122.5±20.09 cm, Undurkhaan station 153.6±16.6 cm and Choibalsan station 203.7±54.38 cm. Also they have positive correlation between annual precipitation (PPT) and water level of river (R2=0.5459, R2=0.3525), and negative correlation between air temperature and water levels of river (R2=0.1915, R2=0.461). This study calculates the possible water volume for collecting rainwater. Mungunmorit is chosen for some advantages. It will be possible to harvesting on the average 51 million m3 water in spring and summer season according to calculation for 10 years. It may increase the volume of water in some year with high precipitation. The collected water can be used for domestic and water consumption of Ulaanbaatar City. Water levels may decrease with increasing air temperature due to climate. Therefore, development of rainwater harvesting system is necessary in the near future. |
