乌伦古湖水体矿化度和氟化物浓度的年际变化及模拟

为研究乌伦古湖矿化度和氟化物浓度与各水量因子间的定量关系,本研究以水量平衡和物质平衡为基础,把影响湖水水质的原因分为降雨、蒸发、河流补给、地下水补给以及地下水流出5个水量因子,定量分析湖水矿化度和氟化物浓度与各水量因子之间的关系,并且预测了湖水矿化度和氟化物浓度的动态变化.结果表明,地下水输出流量决定了湖水中矿化度和氟化物浓度,地下水输出流量越大,湖水中的矿化度和氟化物浓度越小.2010年至今乌伦古湖水位的升高导致了地下水输出流量增大,乌伦古湖内的矿化度和氟化物浓度均呈缓慢下降趋势,模型预测新的稳态下湖水中矿化度为1.68 g/L,氟化物浓度为1.70 mg/L,在地下水输出流量不变的情况下达到新的稳态所需时间大约为50 a.

Modeling temporal changes in salinity and fluoride concentration of Lake Ulungur in Xinjiang, China

In order to evaluate the quantitative relationship between salinity and fluoride concentration and their control factors in Lake Ulungur in Xinjiang, China, this study develops a model for predicting stable state and dynamic water salinity based on water mass balance and solute balance. The input parameters are rainfall, evaporation, river recharge, groundwater recharge, groundwater outflow, and their associated salinity. The concentration of fluoride can also be modeled following the same approach, which provides another constraint on input parameters. The results show that the groundwater outflow significantly affects the salinity and fluoride concentration in lake water, with increasing outflow leading to lower salinity and fluoride concentration in Lake Ulungur. The rise of lake water level leads to increased outflow of groundwater in Lake Ulungur between 2010 and 2020, and the salinity and fluoride concentration in lake water decreased slowly. Our model predicts that the salinity of the Lake Ulungur in the new stable state is 1.68 g/L, and the concentration of fluoride is 1.70 mg/L, but it will take roughly 50 years to reach the new stable state given that the outflow rate remains constant.