Affiliation:
1. Key Laboratory of Water Resources Utilization and Protection, Inner Mongolia Agricultural University, Hohhot 010018, China
Abstract
The water level of Lake Hulun has changed dramatically in recent years. The interannual interaction between groundwater and lake water is an important factor affecting Lake Hulun’s water level. Vertical recharge between groundwater and the lake is particularly important. Based on an analysis of differences between the hydrogeochemical and water quality characteristics of the spring water, the lake water, and the surrounding groundwater, the source and recharge mechanism of the spring water in the vertical recharge lake are determined. The results show that spring water is exposed at the bottom of Lake Hulun, and there are obvious differences between spring water and lake water in lake ice thickness, ion characteristics, and water quality characteristics. For example, the ice thickness at the spring site is only 6.8% of the average ice thickness of the lake, and there is a triangular area directly above the spring water area that is not covered by ice; the ion contents of the spring water at the lake bottom were less than 50% of those in the lake water; and the NH4+-N content of the spring water at the lake bottom was only 3.0% of the mean content of the lake water. In addition, the total nitrogen (TN), dissolved oxygen (DO), and NH4+-N contents of the spring water at the lake bottom all fall outside the range of contents of the surrounding groundwater. In general, the source of the spring water at the lake bottom is not recharged by the infiltration recharge of the phreatic aquifer but by the vertical recharge of the confined aquifer. Additionally, the Lake Hulun basin may be supplied with confined water through basalt channels while it is frozen. The vertical groundwater recharge mechanism may be that spring water at the lake bottom is first supplied by the deep, confined aquifer flowing through the fault zone to the loose-sediment phreatic aquifer under the lake, and finally interacts with the lake water through the phreatic aquifer.
Funder
National Natural Science Foundation of China
Natural Science Foundation of Inner Mongolia under contract
National Basic Research Program of China
Reference62 articles.
1. Satellites reveal widespread decline in global lake water storage;Yao;Science,2023
2. Analysis of water balance of Lake Hulun based on digital remote sensing images;Chen;Water Resour. Prot.,2020
3. Water level changes of Lake Hulun in Inner Mongolia derived from Jason satellite data;Li;J. Vis. Commun. Image Represent.,2019
4. Analysis of surface and groundwater changes of the Lake Hulun based on multisource data;Wu;Remote Sens. Technol. Appl.,2021
5. ICESat/GLAS-derived changes in the water level of Lake Hulun, Inner Mongolia, from 2003 to 2009;Li;Front. Earth Sci.,2018