this study was carried out to determine the appropriate size of caspian trout ( salmo caspius kessler, 1877) juveniles for releasing into the rivers that enter south of the caspian sea for stock enhancement, or possibility of cage culture in the caspian sea. a total of 1611 specimens in 4 weight groups of 5, 10, 15 and 20g were exposed to 3 salinity trials which include caspian sea water (11- 1...

lack of sewage collection systems, percolation of surface waters, and seepage of wells have raised the groundwater table in shiraz area in the south of iran. the growing population generates environmental pollution resulting in the degradation of the quality of surface and groundwaters used for agriculture. inorganic and organic pollutants have been traced in shiraz water resources. heavy metal...

dry areas near the sea can obtain fresh water through solar distillation of saline sea water resources. however, these solar distillation sites produce wastewater as a result of desalination of sea water with high salt concentration. waste must be disposed of with the least effect on the receiving environment (sea, in most cases). initial dilution and its characteristics play important roles in...

A study was made of the diffusion of the red pigment echinochrome from the eggs of the sea urchin, Arbacia punctulata, into sea water. Unfertilized eggs retained their pigment, over periods of hours. Outward diffusion of pigment from unfertilized eggs normally is entirely negligible, or does not occur at all. Enchancing the calcium or potassium content of the artificial sea water (while retaini...

We propose that amino acids in natal stream water have Important roles in Pacific salmon homing. This study hypothesized that amino acids found in natal stream water have a role in the ability of mature male chum salmon (Oncorhynchus keta) to home to the Osaru River (OR), Hokkaido, Japan. Behavioral experiments were conducted in a two-choice test tank using various combinations of control water...

A wave driven sea-water pump which operates by resonance is described. Oscillations in the resonant and exhaust ducts perform similar to two mass-spring systems coupled by a third spring acting for the compression chamber. Performance of the pump is optimized by means of a variable volume air compression chamber (patents pending) which tunes the system to the incoming wave frequency. Wave tank ...

evaporation from the soil surface has an important role in the water balance model in nature, so that the major part of rain fall and irrigation water in arid and semi-arid regions is lost via evaporation from the soil surface. in such areas, there are some regions with high water table and because of evaporation from the soil surface, salts accumulation also occur in the soil surface. so evapo...

we investigated the response of sea buckthorn to drought in a nursery experiment that has been studied for the first time in the world for iranian sea buckthorn. biomass and physiological differences in response to drought were compared between four elaeagnus rhamnoides seedlings inhabited in qazvin province origin seeds of iran. the experimental design included four water regimes including 2, ...