Groundwater resources from karst aquifers play a major role in the water supply in karst areas in the world, such as in Switzerland. Defining groundwater protection zones in karst environment is frequently not founded on a solid hydrogeological basis. Protection zones are often inadequate and as a result they may be ineffective. In order to improve this situation, the Federal Office for Environ...

Despite the Sahara being one of most arid regions on Earth, it has experienced rainfall conditions in past and could hold plentiful groundwater resources. Thus, is precious water resources this region, which suffers from shortage due to limited caused by climatic conditions. This article will assess knowledge-driven techniques employed develop a model integrate multicriteria derived geologic, g...

Deep groundwater aquifers are poorly characterized but could yield important sources of water in California and elsewhere. Deep aquifers have been developed for oil and gas extraction, and this activity has created both valuable data and risks to groundwater quality. Assessing groundwater quantity and quality requires baseline data and a monitoring framework for evaluating impacts. We analyze 9...

Riparian zones can provide a protective buffer between streams and adjacent land-based activities by removing nitrate from shallow groundwater flowing through them. Catchment-scale waterquality models are useful tools for predicting catchment behaviour under various climatic conditions and land-use scenarios. In this paper, we use the Riparian Nitrate Model (RNM) to investigate the potential ro...

The U.S. Department of Interior has identified the Truckee River basin as highly likely for potential water supply conflict in the future. A critical water supply to the Truckee River is outflow from Lake Tahoe, and surface and groundwater contributions from the Martis Valley hydrographic area. This paper highlights the development of an integrated surface water and groundwater model, GSFLOW, i...

Our ability to identify and manage riparian sites for groundwater nitrate (NOAh) removal is limited by uncertainty surrounding the relative importance of plant uptake vs. microbially mediated removal processes. Microcosm studies often demonstrate negligible transformation rates in the subsoil of riparian forests, even in situations where groundwater well networks showed substantial groundwater ...

From 2012 to 2015, we investigated methane (CH4) distribution, air−sea fluxes, and sediment−water fluxes in an aquaculture bay (Sanggou Bay, China), and estimated the input of CH4 from potential land sources including rivers and groundwater. Surface water CH4 in the bay ranged from 3.0 to 302 nM, while bottom CH4 was usually higher due to sediment release. Water column CH4 in summer and autumn ...

Generally, alluvial basins of arid and semiarid zones are the places with excessive groundwater withdrawal, and also they have a high potential for land subsidence. Excessive groundwater withdrawals have caused severe land subsidence in Tehran, Iran. At present, the maximum land subsidence rate is 36 cm/year, covering an area of nearly 530 km2. In the 2000s, as a result of economic and populati...

The complex variable boundary-element method is routinely used to determine the complex potential, h 1⁄4 / þ iw, at any position, z 1⁄4 xþ iy, internal to the flow domain. We reverse this mapping by exactly determining the complex position for specified complex potentials––in effect solving for zðhÞ instead of hðzÞ. Direct calculation of the physical location, 1⁄2x; y , of potential, 1⁄2/;w , i...

[1] Yearly rainfall totals in wet-to-dry climate transition zones show marked multiyear periods of dry and wet anomalies. These are said to originate from large-scale external forcings (e.g. SST anomalies) and enhanced by land-atmosphere coupling through soil moisture, vegetation and surface albedo. We explore the hypothesis that the degree of persistence in rainfall may be partly caused by gro...