An alluvial aquifer can be described as a groundwater system, generally unconfined, that is hosted in laterally discontinuous layers of gravel, sand, silt and clay, deposited by a river in a river channel, banks or flood plain. In semi-arid regions, streams that are associated with alluvial aquifers tend to vary from discharge water bodies in the dry season, to recharge water bodies during cert...

In semi-arid to arid regions, both anthropogenic sources (urban and agriculture) deeper Critical Zone (groundwater with long flow paths water residence times) may play an important role in controlling chemical exports rivers. Here, we combined two isotope tracers: uranium ratios ( 234 U/ 238 U) boron (δ 11 B), the 87 Sr/ 86 Sr identify quantify multiple solute (salinity) Rio Grande river southe...

Arid zones have been affected during the quaternary by a large hydrological and climate variability. This change of processes has shaped the landscape leaving the signature of former paleodrainage and sedimentological features. Using the radar SAR images matched with the detailed topography, obtained from the SRTM (Shuttle Radar Topography Mission) data and ERS interferometry, it is possible to...

Locating additional long-term groundwater resources in semi-arid regions of developing countries with growing populations is an expensive undertaking. Simple geographic information system (GIS) techniques can be utilised to facilitate efficient application of expensive geophysical techniques and test-drilling by functioning as an interdisciplinary integration and decision-making tool, especiall...

Ross River virus (RR) is a mosquito-borne arbovirus responsible for outbreaks of polyarthritic disease throughout Australia. To better understand human and environmental factors driving such events, 57 historical reports on RR outbreaks between 1896 and 1998 were examined collectively. The magnitude, regularity, seasonality, and locality of outbreaks were found to be wide ranging; however, anal...

The Tibagi River, located in southern Brazil, is associated with a significant degree of environmental heterogeneity, along its 550 km extension. There is concern about the integrity of this river's ecosystem, as human interference has been increasing. Aegiphila sellowiana (Lamiaceae) is an important pioneer tree species, commonly found near rivers; the fruit is consumed by avifauna. We s...

BACKGROUND Most groundwater conservation and management efforts focus on protecting groundwater for drinking water and for other human uses with little understanding or focus on the ecosystems that depend on groundwater. However, groundwater plays an integral role in sustaining certain types of aquatic, terrestrial and coastal ecosystems, and their associated landscapes. Our aim was to illumina...

heavy precipitation plays a significant role in arid and semi-arid regions of iran. in order to understand the effect of blocking high system on rainfalls in northwest iran during 25 - 28 october 2008, meteorological conditions including pressure, wind fields and temperature at multiple levels of the atmosphere were analyzed. sea level pressure, the 1000-500 hpa thickness, perceptible water, re...