Species composition, density, and temporal dynamics of zooplankton were studied in six reservoirs in a semi-arid region in tropical northeastern Brazil (Rio Grande do Norte state). All the reservoirs are highly eutrophic, with high contents of total nitrogen (minimum of 1200 µg.L(-1)) and total phosphorus (minimum of 10 µg.L(-1)), and extremely high algal biomass was registered (surpassing 20 µ...

Construction of small reservoirs affects ecosystem processes in numerous ways including fragmenting stream habitat, altering hydrology, and modifying water chemistry. While the upper and middle Chattahoochee River basins within the Southeastern United States Piedmont contain few natural lakes, they have a high density of small reservoirs (more than 7500 small reservoirs in the nearly 12,000 km ...

Portuguese freshwater reservoirs are important socio-economic resources, namely for recreational use. National legislation concerning bathing waters does not include mandatory levels or guidelines for cyanobacteria and cyanotoxins. This is an issue of concern since cyanotoxin-based evidence is insufficient to change the law, and the collection of scientific evidence has been hampered by the lac...

An important aspect of geothermal resource assessment methodology is the development of geothermal resource models consistent with the production histories of exploited geothermal fields. The primary method applied in past United States Geological Survey (USGS) assessments was the volume method, in which the recoverable heat is estimated from the thermal energy available in a reservoir of unifo...

Heavy crude oil is known as oil that is highly viscous and of a higher density than that of conventional oil. Sand reservoirs containing heavy oil generally consist of unconsolidated sediments deposited at a shallow burial depth, with high porosity and permeability. In seismic exploration, acoustic impedance inversion is a commonly used tool in reservoir prediction. However, due to the unconsol...

Enhanced Oil Recovery (EOR) is a well-known method to increase oil production from oil reservoirs. Applying EOR to a new reservoir is a costly and time consuming process. Incorporating available knowledge of oil reservoirs in the EOR process eliminates these costs and saves operational time and work. This work presents a universal method to apply EOR to reservoirs based on the available data by...

paracobitis rhadinaea , a member of the family nemacheiliidae, originally described by regan in 1906 from sistan basin, is poorely known by the rare materials. the inadequately studied species is redescribed on the base of freshly collected materials. the species differs from all other paracobitis species by combination of the following characters: stout and elongated body; large size, up to 28...

This paper aims to compare alpha and beta diversities of planktonic microcrustaceans from three reservoirs located nearby in a tropical semiarid basin. Our hypothesis was that alpha and beta diversities of the community are different, although the ecosystems are located close to each other. We carried out two sampling campaigns: dry and rainy seasons. The sampling of microcrustaceans and enviro...

Primary productivity, Secchi disc visibility, chlorophyll, and nutrient concentrations were studied in Wagon Train and Stagecoach reservoirs during the years 1969 and 1970. The reservoirs are separated by a distance of only 12 km and are similar in nutrient content and circulation pattern. Furthermore, in both reservoirs 92-100% of the productivity occurs in the upper two meiers. However, the r...

man-made reservoirs constructed on running waters, where a decrease in flow velocity and anincrease in flocculent settling occurs, create perfect conditions for the deposition of allohtonic matter andadsorbed pollutants, such as toxic polychlorinated dibenzo-p-dioxins (pcdds) and polychlorinateddibenzofurans (pcdfs). the results obtained from the research on a cascade of five small reservoirs l...