Spatial variations of river–groundwater interactions from upstream mountain to midstream oasis and downstream desert in Heihe River basin, China

Abstract

The Heihe River basin consists of three different characteristic regions: upstream mountain area, midstream oasis region, and downstream desert region. Understanding the river–groundwater interactions in different river reaches is important for sustainable water resources management. In this study, river–groundwater interactions in three different river regions are investigated by the analysis of geophysical characteristics, meteor-hydrological characteristics, agricultural irrigations, and channel water balance equation in the river reaches in different seasons. Results indicate that the river–groundwater interactions vary geographically in the three different regions, and change seasonally with the strongest interactions during the summer. Groundwater discharges into the river in the upstream mountainous reach (annual 2.57 × 108m3) while the river water seeps into aquifers in the downstream desert reach (annual 10.39 × 108m3). In the midstream oasis region, pumping water for agriculture irrigation significantly affects the river–groundwater interaction. The river loses water to the ground during the major- and medium-irrigation periods, and gains water from groundwater during the minor-irrigation period in the midstream reach. The characteristics of the river–groundwater interactions are primarily dominated by physiographic features and precipitation in the upstream mountainous region, by human activities and precipitation in the midstream oasis region, and by evaporation and human activities in the downstream desert region.

Responses of two desert riparian species to fluctuating groundwater depths in hyperarid areas of Northwest China

“…The two species differ in their distributions in this region. There have been two or three water releases from the upstream each year, resulting in approximately 10.39 × 10 8 m 3 of river water that infiltrated into the groundwater of the downstream areas (Cai et al, 2015). The two groups rarely appear in the form of large area of mixed stands.…”

“…Since 2000, an ecological water conveyance project (EWCP) has been implemented to restore the degraded ecosystems in the downstream HRB. There have been two or three water releases from the upstream each year, resulting in approximately 10.39 × 10 8 m 3 of river water that infiltrated into the groundwater of the downstream areas (Cai et al, 2015). The implementation of the EWCP dramatically altered the natural hydrology scenarios in the riparian areas of the downstream HRB.…”

Influencing Factors of the Spatial–Temporal Variation of Layered Soils and Sediments Moistures and Infiltration Characteristics under Irrigation in a Desert Oasis by Deterministic Spatial Interpolation Methods

“…From the ecosystem function, the mountain system provides water resources for the oasis, which serves as a site for agricultural production and social development, while the desert is the vast moisture dissipation region [56]. For the stream link, the MODS is the ordered pattern of upstream, midstream, and downstream [57]. With regard to soil permeability, the hydraulic conductivities are larger in the east than that in the west, as shown in Figure 2.…”

Assessing Underground Water Exchange Between Regions Using GRACE Data

“…To improve the accuracy of the simulation, many methodologies have been proposed to address these problems and have made important achievements (Ajami et al, 2007; Rojas et al, 2010). The estimation of boundary fluxes, however, remains unresolved as this process requires both an accurate physical representation of the system and its differentiation from the adjacent groundwater system (Cai et al, 2016; Ye et al, 2010). Attempts are generally made to use no‐flow or constant head boundary, but this may not be always true and is also far from reality.…”