the sefidrud dam was constructed and made operational in iran in 1962. the reservoir lost a considerable amount of its storage capacity in the first two decades of its operation when about 800 mcm sediment deposited in it and by considering the total capacity, 1800 mcm, the live storage capacity was reduced by 45 percent in 1980. the gilan project authorities have attempted to recreate the rese...

The relict population of Neotoma fl oridana occurring along the Niobrara River in north-central Nebraska was found to have a diet composed of 38 types of food items of which 37 types were plants. Unique features of the summer diet of this population were a higher than expected use of red cedar (Juniperus virginiana) and invertebrates as food items.

—During spring, harbor seals Phoca vitulina feed at night under two bridges spanning the Puntledge River in Courtenay, British Columbia, Canada. Positioned parallel to one another, ventral side up, the seals form a feeding line across the river to intercept thousands of out-migrating salmonid smolts. During a 4week observation period in the spring of 1996, we attempted to disrupt the seals’ fee...

knowledge of habitat requirements of aquatic animals plays an important role in fisheries and protection programs of aquatic ecosystems. hence, this study was conducted to investigate the suitability indexes of habitat use and habitat suitability index (hsi) of barbus cyri in its distribution range in tootkabon river. a number of environmental variables, including elevation, water depth, river ...

As the human population in the piedmont of South Carolina grows, the release of treated effluents from wastewater-treatment plants (WWTPs) will increasingly affect the chemical composition and biogeochemical processes of the region’s rivers. We examined the impact of WWTP effluent on the solute chemistry of one such river, the Bush River, South Carolina, which experienced extremely low flow dur...

The Minnesota River Basin (MRB), situated in the prairie pothole region of the Upper Midwest, contributes excessive sediment and nutrient loads to the Upper Mississippi River. Over 330 stream channels in the MRB are listed as impaired by the Minnesota Pollution Control Agency, with turbidity levels exceeding water quality standards in much of the basin. Addressing turbidity impairment requires ...

drought is a complex natural phenomenon that can occur in any climate. hydrologic drought in the river flow of arid and semi-arid areas causes serious shortages, threatens the quality of life, and impacts on the economy. understanding this feature is then essential for the management of water resources. hydrologic drought in the sense of deficient river flow is defined as the periods that river...

Abstract The performance of pumps installed in pumping stations depends greatly on vortex formation at pipe intakes. Using numerical simulations and experimental methods, this study focuses water intake system a station under the tidal conditions Bahmanshir River. consisted suction fine screen. Realizable k – ε turbulence model together with volume fluid (VOF) two-phase (water–air) are used to ...