Intermontane basins in the Trans-Pecos region of westernmost Texas and northern Chihuahua, Mexico, are target areas for disposal of interstate municipal sludge and have been identified as possible disposal sites for low-level radioactive waste. Understanding ground water movement within and between these basins is needed to assess potential contaminant fate and movement. Four associated basin a...

Hydrology is modeling, starting from the moment a hydrologist stands on a hill and develops a concept of the system; continuing with application of an analytical model such as Darcy’s law, the Theis equation, or chemical equilibria; and sometimes extending to elaborate numerical models. Darcy created the first quantitative ground water model in 1856, driven by the practical goal of providing a ...

Seepage-face boundaries are common features of unconfined ground water flow. These boundaries exist at the intersection of an unconfined aquifer and a surface water body such as a lake, river, or wetland. The existence of a seepage-face boundary is necessary to provide a physical transition between the internal water-table boundary and the external equipotential boundary when an unconfined aqui...

Understanding how spring runoff is generated in East Siberia during the spring thaw is important to predicting river flows. To evaluate the snowmelt runoff generated, a simple runoff model was developed. The model involves processes of water and energy balance within the snowpack and energy balance within soil, snowmelt infiltration into the frozen ground, and surface runoff. The model reproduc...

We have used Landsat-5 TM and Landsat-7 ETM+ images together with simultaneous ground-truth data at sample points in the Doñana marshes to predict water turbidity and depth from band reflectance using Generalized Additive Models. We have point samples for 12 different dates simultaneous with 7 Landsat-5 and 5 Landsat-7 overpasses. The best model for water turbidity in the marsh explained 38% of...

Introduction and large scale production of synthetic halogenated organic chemicals over the last 50 years has resulted in a group of contaminants which tend to persist in the environment and resist both biotic and abiotic degradation. The low solubility of these types of contaminants, along with their toxicity and tendency to accumulate in food chains, make them particularly relevant targets fo...

Information based agriculture (IBA) includes matching of agronomic practices with soil and water characteristics and their spatial variability for enhancing productivity. An attempt was made to derive agriculture management zones based on soil and water characteristics for sustainable agricultural production in Mansa district (Punjab, India). Based on physiographic analysis and semi detailed so...