An Improved Model for the Evaluation of Groundwater Recharge Based on the Concept of Conservative Use Potential: A Study in the River Pandeiros Watershed, Minas Gerais, Brazil

Abstract

Water resources have been increasingly impacted due to the growth of water demand associated with environmental degradation. In this context, the mapping of groundwater recharge potential has become attractive to water managers as it can be used to direct public policies and conserve this natural asset. The present study modifies (improves) a spatially explicit model to determine groundwater recharge potential at the catchment scale, testing it in the Pandeiros River basin located in the state of Minas Gerais, Brazil. The model is generally based on the water balance approach and the input variables were compiled from institutional sources and processed in a Geographic Information System. The novelty brought by the aforementioned modification relates to the coupling of physical variables (conventional way) and land management practices (introduced here) in the estimation of a percolation factor. The role of land management practices for percolation was assessed by the so-called Conservative Use Potential (PUC) method, which classifies the areas of a river basin in terms of their potential for sustainable use. The results were validated by an independent method, namely the recession curve method based on the interpretation of hydrographs. In general, the groundwater recharge potential is favored in flat to gently undulating areas and forested regions, as well as where the landscape is characterized by well-structured soils, good drainage conditions and large hydraulic conductivity. The map of groundwater recharge potential produced in this study can be used by planners and decision makers in the Pandeiros River basin as a tool to achieve sustainable use of groundwater resources and the protection of recharge areas.

Identification of the Dominant Factors in Groundwater Recharge Process, Using Multivariate Statistical Approaches in a Semi-Arid Region

“…A high association between humidity and land use can be due to a large area of agricultural fields in the study zone. Studies have demonstrated that the zones with high groundwater recharge potential are located in areas with dense vegetation cover coupled with flat relief and consolidated and structured soils [126].…”

Groundwater Recharge in the Cerrado Biome, Brazil—A Multi-Method Study at Experimental Watershed Scale

“…The correct characterization of this hydrological process is fundamental to integrated water resources management [1][2][3][4][5][6][7], although it is complex and difficult to quantify [8][9][10]. Temporal and spatial variability adds to the lack of data and resources, which prevents the actions taken by managers and researchers from being correctly fulfilled when facing scenarios of overexploitation, inordinate land use, pollution, and other environmental damage [11][12][13][14]. Depending on the particularities of a region, the extent of the groundwater recharge process can go beyond even national political and administrative borders [15,16].…”

“…Some methods, for example, those based on flow direct measurements, can generate good results when obtaining point values, but may be unable to characterize the spatial variability of the process. Distributed methods are typically avoided due to the amount and variety of data required [7,12,13,29]. This methodological difficulty is not restricted to groundwater recharge research, and a way to overcome it is through the adoption of an experimental watershed as the study area.…”

Watersheds, Anthropogenic Activities and the Role of Adaptation to Environmental Impacts

“…In the rural environment, the alternatives comprise the storage of rainwater in small dam lakes (rainwater harvesting), to be used in the irrigation of cropland or combating wildfires [19,20]. In the urban environment, especially around the large metropolises, the conjunctive use of various sources (surface water, groundwater, desalinized water and recycled wastewater) can be a reliable path to adaptation, aided by controlled groundwater recharge where possible [21][22][23][24][25]. The incentive to produce clean drinking water in headwater catchments through the adaptation of land uses (e.g., a shift from extensive monocultures to agro-forestry systems), aiming at the reduction of treatment and hence final costs, is a promising adaptation measure.…”