The Ecological Limits of Hydrologic Alteration (ELOHA) is a new framework for broadly assessing environmental flow needs when time or resource constraints preclude in-depth studies for all rivers in a region. The main steps of ELOHA are to: (1) build a hydrologic foundation, (2) characterize river types according to their flow regimes and geomorphic features, (3) compute present-day degrees of ...

salmas plain is located at the west of uremia lake and at the 75 km of north of uremia city. the main river of the plain, called zulachai, is drained into uremia lake. salmas aquifer is one of the coastal aquifers of uremia lake and has hydraulic connection with the lake. the recent draught occurrences and increased water consumption in agriculture and drinking sections water have not only caus...

Efforts have increased to measure nitrate losses from farmland under different management practices due to environmental and public concerns over levels of nitratenitrogen (NO3-N) in surface and ground waters. This study evaluated the effect of conventional tillage (CT) and strip tillage (ST) practices and three N application rates on NO3-N concentrations in soil water at a 76 cm depth under ir...

Radiocarbon dating of ground water is used in combination with the primary measurements of classical hydrological and chemical analyses. Radiocarbon dating will produce the best results when it involves multiple measurements or sequential sampling. The most useful data come from these comparisons and not from absolute ages. In the case of multiple measurements, the apparent ages of the ground w...

abstract the use of water sources has increased due to extend of agricultural activity for answering food needs of increasing population. while because of exploitation and consumption of water, the use of this restricted resource is not appropriate. consequently in many districts of country the head level of ground water aquifers have been fallen and water level is negative. so, application of ...

The paper presents the case study of the current formation of a Brazilian pit lake from an iron ore mining activity. The water used for the filling of the lake comes from rain, ground water and the complementary pumpage from a close river. At its final stage, which will be reached around year 2018, Lake Aguas Claras will have a surface area of 0.67 km2 and the depth of 234 m, which will make it...

1 Ground water is an almost ubiquitous source of generally high-quality fresh water. These characteristics promote its widespread development, which can be scaled and localized to demand, obviating the need for substantial infrastructure1. Globally, ground water is the source of one third of all freshwater withdrawals, supplying an estimated 36%, 42% and 27% of the water used for domestic, agri...

The age of ground water in any given sample is a distributed quantity representing distributed provenance (in space and time) of the water. Conventional analysis of tracers such as unstable isotopes or anthropogenic chemical species gives discrete or binary measures of the presence of water of a given age. Modeled ground water age distributions provide a continuous measure of contributions from...