fish species diversity, distribution and abundance were studied in the sardabrud and chalus rivers, in the southern caspian sea basin, during 1992 and 1993 in five and four stations respectively, by monthly collections using electrofishing device. in total, 3200 fish specimens, including 15 species in sardabrud river and 12 species in chalus river, were investigated. the fish comprised of 13 ge...

the present study reports range extansion of moenkhausia oligolepis to the pindaré river drainage, of the mearim river basin, and itapecuru river basin, maranhão state, northeastern brazil. this species was previously known only from venezuela, guianas, and the amazon river basins. in addition, we present some meristic and morphometric data of the specimens herein examined and discuss on its di...

A total of 14 perfluorinated compounds (PFCs) were quantified in river water samples collected from tributaries of the Pearl River (Guangzhou Province, south China) and the Yangtze River (central China). Among the PFCs analyzed, perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) were the two compounds with the highest concentrations. PFOS concentrations ranged from 0.90 to 99 ng...

  Mahisefid is the most popular fish in Iran with the highest economic value. The analysis of mitochondrial DNA has been extensively used as a marker for population genetic studies and is a powerful tool in studies of gene flow and evolutionary biology. Two hundred ninety four samples were collected from Sefid Rud River (100), Lamir River (98), Shir Rud River (48) and Tajan River (48) during s...

Fresh Water Rivers are one of the most important aquatic ecosystems in arid and semi-arid regions of Iran in point of biodiversity and drinking water views. Damghanroud River is one of these rivers at Semnan province that during past years has been threatened by drought and anthropogenic pollutions. This river supplies some parts of drinking water of Damghan city and some vicinity villages. The...

Considering characteristics of high river density, special underlying surface in plain river network region, and municipal drainage system function, river network drainage unit model is proposed, which is defined as a region surrounded by main river or embankment. Flood storage variety and control projects regulation of small rivers in each unit is simulated. With drainage catchment as an objec...

Papers published in Hydrology and Earth System Sciences Discussions are under open-access review for the journal Hydrology and Earth System Sciences Abstract Major environmental stressors of boreal and sub-arctic rivers are hydrological changes and global warming and both factors will significantly influence the future evolution of the river chemistry in high latitudes. We tested the hypothesis...

Recent geochemical and hydrological findings show that the water quality of the base flow of the Lower Jordan River, between the Sea of Galilee and the Dead Sea, is dependent upon the ratio between surface water flow and groundwater discharge. Using water quality data, mass-balance calculations, and actual flow-rate measurements, possible management scenarios for the Lower Jordan River and thei...