In many semi-arid basins during extended periods when surface snowmelt or storm runoff is absent, groundwater constitutes the primary water source for human habitation, agriculture and riparian ecosystems. Utilizing regional groundwater models in the management of these water resources requires accurate estimates of basin boundary conditions. A critical groundwater boundary condition that is cl...

The hydrological model WASA (Model of Water Availability in Semi-Arid Environments) has been developed as a deterministic, spatially distributed model, consisting of conceptual, process-based approaches, to quantify water availability in large semi-arid regions. Water availability can be calculated with a daily resolution and on different spatial levels. The model has been applied by Güntner (2...

Approximately 5.5 x 109 g (4.0 x 105) of mercury was discharged into the Carson River Drainage Basin of west-central Nevada during processing of the gold- and silver-rich Comstock ore in the late 1800s. For the past 13 decades, mercury has been redistributed throughout 500 km2 of the basin, and concentrations are some of the highest reported values in North America. This article documents the c...

In recent decades, China has been experiencing rapid economic development, population growth and urbanization. These processes have stressed the shortages of water resources in China, especially in the arid regions of northwestern China. In order to sustain the expanding cropland, people increased groundwater exploitation in these regions. The purpose of this study was to quantitatively analyze...

For the frangible ecological environment, it is very important to reasonably develop and utilize groundwater resources in Northwest China. Shallow groundwater level is an essential factor related to the eco-environmental problems such as oasis degeneration and land salinification. The lack of groundwater dynamic data is a critical concern for water resources management in the arid region. This ...

This study investigated the relationships between fish condition and environmental variables in Barbus sclateri from semi-arid freshwater ecosystems in the south-eastern Iberian Peninsula. Two main habitats were studied: semi-arid streams characterized by strong seasonal fluctuations in flow level (droughts and floods) and reservoirs (artificial ecosystems characterised by waters of high conduc...

Water is essential for life. Specifically in the oases of inland arid basins, water is a critically limited resource, essential for the development of the socio-economy and the sustainability of eco-environmental systems. Due to the unique hydrological regime present in arid oases, a moderate groundwater table is the goal of sustainable water management. A shallow water table induces serious se...

In this paper, we present the applications of spatial technologies-Geographic Information Systems (GIS) and remote sensing-in the international monitoring of river basins particularly analyzing the ecological, hydrological, and socio-economic issues along the Senegal River. The literature on multinational water crisis has for decades focused on mediation aspects of trans-boundary watershed mana...

Previous studies that quantified variations in runoff have mainly focused on the combined impacts of climate and human activities or climate and land cover change. Few have separated land cover change from human activities, which is critical for effective management of water resources. This study aims to investigate the impact of changing environmental conditions on runoff using the Soil and Wa...

INTRODUCTION An understanding of the feeding ecology of the red-billed quelea (Quelea quelea) is necessary for a comprehensive assessment of the potential impact of this species on cereals development. Queleas are reported to subsist primarily on wild Gramineae (Ward 1965a; Gaston 1976), but their mobility and tendency to feed in large aggrega-tions readily adapts them to becoming a major cerea...