Humans have exerted large-scale changes on the terrestrial biosphere, primarily through agriculture; however, the impacts of such changes on the hydrologic cycle are poorly understood. The purpose of this study was to test the hypothesis that the conversion of natural rangeland ecosystems to agricultural ecosystems impacts the subsurface portion of the hydrologic cycle by changing groundwater r...

This paper considers the target patrolling problem which asks a set of mobile data collectors (or data mules) to efficiently patrol a set of given targets. Since the time interval (also referred to visiting interval) for consecutive visits to each target reflects the monitoring quality of this target, the goal of this research is to balance the visiting interval of each target. This paper first...

One-km resolution MODIS-based mean annual evapotranspiration (ET) estimates in combination with PRISM precipitation rates were correlated with depth to groundwater (d) values in the wide alluvial valley of the Platte River in Nebraska for obtaining a net recharge (Rn) vs. d relationship. MODIS cells with irrigation were excluded, yielding a mixture of predominantly range, pasture, grass, and ri...

Recent studies have shown that environmental energy harvesting technologies have the potential to provide perpetual operation to rechargeable sensor networks. However, due to the large variations of the ambient energy source, such networks could only support low-rate data services and their performance is influenced by numerous unpredictable environmental factors. In order to bridge this gap to...

Karst is a hydrogeological environment of importance not only for its water resources potential but also for its scenic and economic potential, thereby increasing the intensity of human impact. The uniqueness of karst in this regard stems from its high sensitivity and vulnerability to imposed pressures and its distinctive response to these pressures. Therefore, a clear definition and formulatio...

A new inverse method is developed to simultaneously estimate heterogeneous hydraulic conductivities, source/sink rates, and unknown boundary conditions for steadystate flow in an unconfined aquifer. Unlike objective function-based techniques, the new method does not optimize any data-model misfits. Instead, its formulation is developed by honoring physical flow principles as well as observation...

Groundwater recharge with reclaimed municipal wastewater presents a wide spectrum of technical and health challenges that must be carefully evaluated prior to undertaking a project. This review will provide a discussion of groundwater recharge and its management with special reference to health and regulatory aspects of groundwater recharge with reclaimed municipal wastewater. At present, some ...

Many diverse biological systems are described by randomly moving particles that can be captured by traps in their environment. Examples include neurotransmitters diffusing in the synaptic cleft before binding to receptors and prey roaming an environment before capture by predators. In most cases, the traps cannot capture particles continuously. Rather, each trap must wait a transitory "recharge...

Episodic recharge as a result of infrequent, high intensity precipitation events comprises the bulk of groundwater recharge in arid environments. Climate change and shifts in precipitation intensity will affect groundwater continuity, thus altering groundwater recharge. This study aims to identify changes in the ratio of groundwater recharge and precipitation, the R:P ratio, in the arid southwe...

Groundwater levels rose (an average of 10m) (mostly in 1970’s and 80’s) due to irrigation induced recharge to the groundwater in Coleambally Irrigation Area (CIA). Water table depth rise was a direct result of the net amount of recharge over and above the regional groundwater outflow capacity. Control of net recharge through a range of options is critical to the sustainability of CIA and requir...