Ecological Impacts Induced by Groundwater and Their Thresholds in the Arid Areas in Northwest China

Abstract

Based on the field survey, this paper analyzes the relationship between groundwater and ecological environment in arid and semiarid areas in northwest China. Groundwater in the arid and semiarid areas is a natural resource with economic and ecological values. The concept of the ecological value of groundwater is firstly presented. This ecological value can be reflected in four aspects: (1) the maintenance of base flow in rivers and areas of lakes and wetland; (2) the supply of physiological water demanded by vegetations; (3) the regulation of soil moisture and salt content; and (4) the stability of the geological environment (such as land subsidence etc.). In addition, the threshold system between the ecological environment and multi-dimensional indices as variations in levels of the groundwater table, groundwater quality, water and salt content in the vadose zone as well as groundwater exploitation, are proposed in the arid and semiarid areas. It is expected that the system could provide a scientific basis and technological support for the regulation of the groundwater status and the maintenance of sustainable development of the ecological environment and utilization of water resources.

Topical Collection: Groundwater recharge and discharge in arid and semi-arid areas of China

“…Recharge from disconnected-river seepage is one of the major sources of groundwater recharge in arid areas, and river leakage accounts for more than 60% of the total groundwater recharge in the Yellow River basin (Wang et al 2013). However, human activities have intensified in arid and semi-arid areas since the late 1970s when China started its economic reforms (Wang et al 2018).…”

Spatial and temporal groundwater dynamics in extreme arid basins

“…Groundwater is not only an essential guarantee of water for human production and life (Huang et al, 2022; Shi et al, 2021) but also has an irreplaceable role in the oasis (Lozano et al, 2013). In the arid zone of northwest China, vegetation in artificial and natural oases is strongly dependent on groundwater (Gries et al, 2003; Martinetti et al, 2021; Tamea et al, 2009), providing vegetation water demand (Wang, Wang, et al, 2018; Wang, Yu, et al, 2018), regulating soil water content (Cao et al, 2021), salinity (Wang et al, 2013), and balancing water use in abundant and dry years (Gao et al, 2020; Wada et al, 2012; Wang et al, 2023). However, climate change (Devkota & Gyawali, 2015; Shrestha et al, 2017; Tan et al, 2017) enhanced the impacts of human activities (Riley et al, 2019; Scanlon et al, 2005), turning groundwater evolution more complex.…”

The Surface Crack Extraction Method Based on Machine Learning of Image and Quantitative Feature Information Acquisition Method

“…In western China, especially in arid and semiarid areas, surface cracks are caused by human activities, such as coal mining [1], soil erosion, building damage, vegetation withering, and other geological environment problems caused by surface cracks [2][3][4]. In order to effectively control the damage caused by surface cracks to a geological environment, we need to find a convenient, efficient, and accurate method to obtain crack information, which can be used to study the development regularity of surface cracks and to evaluate the risk in providing guarantees for land reclamation [5].…”