Spatial Patterns and Quantification of Lacustrine Groundwater Discharge Determined Based on ²²²Rn

Abstract

Lakes are widely distributed worldwide and have great economic, environmental, and ecological importance (Zedler & Kercher, 2005). However, under increasing anthropogenic stress, eutrophication has become pervasive in many lakes, with ∼63% of lakes being identified as "eutrophic" in the trophic state classification system (Wang et al., 2018). Groundwater is a component that has long been overlooked in the study of the hydrological cycle and eco-environment of lakes. Recent investigations have shown that lacustrine groundwater discharge (LGD) can exert strong effects on the water budgets and eutrophic status of lakes (

Spatio‐temporal patterns and quantification of lake–groundwater interaction determined in a large water transfer lake

“…Almost all lakes interact with groundwater (Ahmadi et al, 2018; Boreux et al, 2021; Cohen et al, 2016; Winter, 1999). The past investigations have shown that the nutrient concentration via groundwater could be several orders of magnitude higher than that of surface water input (Boreux et al, 2021; Lewandowski et al, 2015; Sun et al, 2022), so the degree of which lakes interact with groundwater strongly affects the water balance and aquatic chemistry as well as aquatic biota in lake water and groundwater (Lewandowski et al, 2015; Rosenberry et al, 2015). However, the importance of hydrological connectivity has usually been ignored due to the unobservable process of lake–groundwater interaction (Chen & Tian, 2021; Kummu et al, 2014).…”

“…However, the importance of hydrological connectivity has usually been ignored due to the unobservable process of lake–groundwater interaction (Chen & Tian, 2021; Kummu et al, 2014). Recent research has demonstrated that accurately quantifying the exchange rate between lake and groundwater is a prerequisite for assessing the derived nutrient load of lake water and surrounding groundwater (Ferencz et al, 2019; Lewandowski et al, 2015; Rosenberry et al, 2015; Sun et al, 2022; Welch et al, 2013). Therefore, it is important to study the lake–groundwater interaction.…”

“…Owing to the heterogeneity of aquifer types, topography, human activity, river location and climate, the exchange rate between lake and groundwater is spatially and temporally variable even in the same lake. The observation of the temporal and spatial pattern of lake–groundwater exchange is helpful to locate the discharge hotspots and lake–groundwater exchange modes (Hare et al, 2017; Sun et al, 2022; Tecklenburg & Blume, 2017) as well as identify the contributions of temporal variable factors (Chen et al, 2020; Hester et al, 2016; Zhou et al, 2022), which improves the understanding of lacustrine hydrology. Although some previous studies have estimated the temporal/spatial variation of lake–groundwater exchange (Kummu et al, 2014; Luo et al, 2016; Santos et al, 2008; Sun et al, 2022), few works have been conducted to quantify the lake–groundwater exchange under spatio‐temporal heterogeneity due to the challenge of conducts.…”

“…The observation of the temporal and spatial pattern of lake–groundwater exchange is helpful to locate the discharge hotspots and lake–groundwater exchange modes (Hare et al, 2017; Sun et al, 2022; Tecklenburg & Blume, 2017) as well as identify the contributions of temporal variable factors (Chen et al, 2020; Hester et al, 2016; Zhou et al, 2022), which improves the understanding of lacustrine hydrology. Although some previous studies have estimated the temporal/spatial variation of lake–groundwater exchange (Kummu et al, 2014; Luo et al, 2016; Santos et al, 2008; Sun et al, 2022), few works have been conducted to quantify the lake–groundwater exchange under spatio‐temporal heterogeneity due to the challenge of conducts. Part of studies showed that the spatial heterogeneity of lake–groundwater exchange can be controlled by the aquifer characteristics (Hester et al, 2016; Lu et al, 2018), topography (Tecklenburg & Blume, 2017), human activities (Chen et al, 2020), and river/channel location (Rocha et al, 2016; Zhou et al, 2022), but the comparison among spatial exchange rates is of no practical significance, while ignoring the change of lake level and groundwater table over time.…”

“…Previous study on lake–groundwater exchange involved various types of lakes, including desert lakes (Cao et al, 2022; Yang et al, 2017a), salt water lakes (Luo et al, 2016), thermokarst lake (Wan et al, 2019), tundra lakes (Dabrowski et al, 2020), small shallow lakes (Yang et al, 2020), large lakes (Sun et al, 2022) and reservoirs (Wang et al, 2021). However, there have been few studies about the groundwater of water transfer lakes.…”