following the collapse of the soviet :union: and independence of former soviet :union:republics, previous economic relations among centralasianrepublics changed and were replaced with the market economy. tensions have emerged between upstream and downstream countries located along transboundary rivers with downstream countries even resorting to threat of military action against possible restric...

Copepods are the main zooplankton assemblages in most tropical and semi-tropical estuaries. In this research, copepod population dynamics were investigated in Helleh River estuary, Persian Gulf during four seasons beginning from summer 2011 to spring 2012.  Samples were taken using plankton net with mesh size of 140 µm and vertical towing from 5 fixed-stations in mid-season. Results showed that...

Background & Aims of the Study: Heavy metals pollution in aquatic ecosystems threats living organisms' health and environment. Hence, the present study aims to assess concentration of lead, chromium, copper, zinc and their ecological risk in the surface sediments of the Bashar River during the summer and winter seasons. Materials & Methods: This is a field study; sampling of...

the investigation at water quality of kelaroud river by hfbi (hilsenhoff’s family–level biotic index) method. in this research task to the water quality of kelaroud river using biotic index hfbi and identifying the society of macroinvertebrates upon level of the family. result of this index with other index compared: ept/ chironomidae, .this task was achieved with in the year 1389-90 with takin...

Lake St. Clair is the smallest lake in the Laurentian Great Lakes system. MODIS satellite imagery suggests that high algal biomass events have occurred annually along the southern shore during late summer. In this study, we evaluated these events and tested the hypothesis that summer bloom material derived from Lake St. Clair may enter Lake Erie via the Detroit River and represent an overlooked...

Recent advances in fluorescence spectrophotometry enable the analysis of river dissolved organic matter. We investigate the potential of detecting sewage pollution in a small, urbanised catchment. Downstream sampling highlighted a summer maximum in tryptophan fluorescence intensity during low flow. No correlation is observed between ammonia and tryptophan fluorescence intensity. In contrast, tw...

In this study, the concentrations of Zn and Cr in downstream waters from Uzunçayır Dam (Tunceli, Turkey) were monitored during spring (March, April, May) and summer (June, July, August) season. Zinc and Cr concentrations in surface water samples were detected using the ICP-MS device. According to the data obtained the lowest Zn and Cr concentrations in the spring season were 65.43±3.2 μg/L in M...

The study identified seasonal habitat use by endangered adult Sakhalin taimen Hucho perryi and the environmental characteristics of their habitat (water depth, amount of riparian forest and sinuosity). Fifteen adult H. perryi with acoustic tags were tracked by towing an acoustic receiver with a canoe in the Bekanbeushi River system in eastern Hokkaido Island, Japan, during each month from late ...

Population structure of the African bonytongue, Heterotis niloticus, was examined in southern Benin within Lake Hlan and a region of the Sô River floodplain located approximately 60 km downstream from the lake. Both locations support important fisheries in which Heterotis is the principal target species during the flood period. Ripe adults comprised over 40% of the population in Lake Hlan, wher...