Analysis of groundwater–lake interaction by distributed temperature sensing in Badain Jaran Desert, Northwest China

Abstract

The Badain Jaran Desert is the second largest desert of China with a total area of 49 200 km2. At least 72 perennial lakes are scattered throughout the desert, sustaining a unique desert–lake ecosystem. Groundwater of various origins was believed to play an essential role in maintaining those desert lakes, but hydrological measurements are lacking due to difficult field conditions. This study applied the distributed temperature sensing technique to continuously measure temperature variations in one of the desert lakes – the Badain Lake – to identify groundwater discharge to the lake based on the temperature differences between groundwater and lake water. Because temperature may be influenced by various unforeseen and temporary factors, it is critical to discern those factors that may affect the temperature such as solar radiation and vertical temperature stratification and to ensure that the temperature variations of the lake water as detected by the distributed temperature sensing are mainly caused by groundwater discharge. A time window was identified during which the groundwater discharge is the dominant factor that determines the temperature pattern of the lake water. The results show that the temperature near the eastern and southeastern lakeshore of the eastern Badain Lake is colder than the average, indicating that this area is the main groundwater discharge zone. Near the northwestern lakeshore adjacent to a sand dune, a weak cold abnormal area was identified, indicating that the sand dune is another recharge source to the lake through channelling the local precipitation toward the lake. The contribution from the sand dune, however, appeared to be less than that from the regional groundwater flow. This study provides the first identification of the temperature abnormal areas, which imply groundwater discharges into desert lakes and contributes to a better understanding of the unique desert–lake ecosystem. Copyright © 2015 John Wiley & Sons, Ltd.

Mesocosm experiments identifying hotspots of groundwater upwelling in a water column by fibre optic distributed temperature sensing

“…FO‐DTS has been used to detect GW discharge at the sediment–water interface in lakes (Blume et al, ; Liu et al, ; Tristram et al, ) and streams (Hare et al, ; Krause et al, ; Lowry et al, ). However, it had not yet been determined how the temperature signal propagates from the sediment–water interface through the water column up to the water surface–atmosphere interface and how the signal is affected by environmental parameters such as weather conditions (clear vs. overcast) and the diurnal cycle of net radiation.…”

“…However, the characterization of weather and diurnal conditions that might have affected the upwelling patterns of the GW heat signal across the water column was not addressed until the present study. For instance, Liu et al () conducted an experiment on the lake bed that took into account environmental factors to determine the best time to detect GW discharge areas with FO‐DTS. Liu et al () worked in a lake that was relatively shallow, which reduced the effect of vertical stratification on the lakebed temperatures during the FO‐DTS measurements.…”

“…In this way, temperature can be monitored through the fibre optic cable up to a distance of several km, with spatial resolutions ranging from 0.3 to 4 m and measurement precision of 0.05 to 0.1 °C when sampling over 30‐s intervals (Hausner et al, ; Selker, Thévenaz, et al, ; van de Giesen et al, ). FO‐DTS has been used to detect GW discharge at the sediment–water interface of lakes (Blume, Krause, Meinikmann, & Lewandowski, ; Liu, Liu, Wang, & Zheng, ; Sebok et al, ) and streams (Krause, Blume, & Cassidy, ; Lowry, Walker, Hunt, & Anderson, ). Here, FO‐DTS is placed in layers of a specific depth above the sediment–water interface, to provide high‐resolution temperature data to quantify the incidence, frequency, persistence, and attenuation of warmer discharging GW that reaches the water surface.…”

Water Loss Due to Increasing Planted Vegetation over the Badain Jaran Desert, China

“…It is widely accepted that the groundwater has been recharging the hundreds of permanent lakes in the BJD under the hyper-arid environment, which are increasing the attraction for tourists [45,[96][97][98][99]. Although the total area of the lake region is small (approximately 20 km 2 ) compared with the whole study region, the groundwater resources underneath the desert are considered to be rich [100].…”

Estimating interaction between surface water and groundwater in a permafrost region using heat tracing methods

“…The pioneering of a vertical high-resolution DTS system for hydrologic applications was presented by Selker et al (2006), 5 which has been widely used in observing a broad range of hydrologic processes (Tyler et al, 2009;Liu et al, 2016). FO-DTS temperature measurement is based on the analysis of the temperature dependent Raman spectra backscatter properties of a laser pulse that is applied to, and propagates through, a fiber-optic cable (Selker et al, 2006).…”