نتایج جستجو برای: 1840 population in downstream bahmanshir river during summer
تعداد نتایج: 17291067 فیلتر نتایج به سال:
In-river phosphorus retention alters the quantity and timings of phosphorus delivery to downstream aquatic systems. Many intensive studies of in-river phosphorus retention have been carried out but generally on a short time scale (2–4 years). In this paper, monthly water quality data, collected by the Environment Agency of England and Wales over 12 years (1990–2001), were used to model daily ph...
Clostridium perfringens (CP) and sulphite reducing clostridia (SRC) densities in the Selangor River, Bernam River and Tengi River Canal were examined between April 2007 and January 2008. Water samples were taken from two or three locations along each river, using either depth-integration or grab sampling methods. The downstream sampling site of the Selangor River, Rantau Panjang, reported the h...
The concentrations of Cd, Pb, Ni and Hg were determined in gill, liver and muscle of Barbus xanthopterus in down streams of Karoon and Dez Rivers during summer 2009. Heavy metal concentrations varied significantly, depending on the types of the tissue in fish species. The levels of heavy metals such as Cd, Pb, Ni and Hg in the Barbus xanthopterus of Karoon River were higher than in B...
Unidirectional water flow results in the downstream-biased, asymmetric dispersal of many riverine organisms. However, little is known of how asymmetric dispersal influences riverine population structure and dynamics, limiting our ability to properly manage riverine organisms. A metapopulation of the freshwater pearl mussel Margaritifera laevis may be sensitive to river currents because mussels ...
Atlantic salmon Salmo salar are often heavily infected by the gill maggot Salmincola salmoneus, but little information exists on the population dynamics of this parasite. Through a combination of in vivo field examination and laboratory analysis of gills from the Alta River S. salar population in northern Norway, we describe the population dynamics of the parasite and suggest a model for the ho...
Mencha River is one of the largest river in the region of Jijel, Algeria. The human activities such as urban discharges, industrial, agricultural and livestock have significant effects on the quality of water. Because of its importance in the agricultural activities and dense population residing at its banks, the river faces several challenges from various anthropogenic activities. This situati...
several studies suggest that invertebrate abundance and richness are disrupted and reset at confluences. thus, junctions contribute disproportionately to the overall aquatic biodiversity of the river. in general terms, authors have reported high abundance and diversity due to the major physical heterogeneity at junctions. however, data are still scarce and uncertainties are plentiful.the impact...
To investigate reasons for the decline of an endangered population of coho salmon (O. kisutch), 190 smolts were acoustically tagged during three consecutive years and their movements and survival were estimated using the Pacific Ocean Shelf Tracking project (POST) array. Median travel times of the Thompson River coho salmon smolts to the lower Fraser River sub-array were 16, 12 and 10 days duri...
The spatial representativeness of gauging stations was investigated in two low-mountainous river basins near the city of Trier, southwest Germany. Longitudinal profiles during low and high flow conditions were sampled in order to identify sources of solutes and to characterize the alteration of flood wave properties during its travel downstream. Numerous hydrographs and chemographs of natural f...
Since 2001, water main drainage of sugarcane farms located in the east side of Karoon River has been deviated to Shadegan lagoon. The average discharge and salinity of the drain water in spring and summer were 20 and 20.5 m3 sec-1 and 17.1 and 13.3 dS m-1, respectively. Therefore, there have been considerable changes in the lagoon water quality when compared to the time before entering the drai...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید