phytoplanktons are the first bio- indicators of pollution in aquatic ecosystems. phytoplankton assemblage and aquatic ecosystems are always influenced by environmental factors therefore these environmental changes and threats must be understood in any ecosystem. phytoplankton are inexpensive and readily available bio- indicators. in the present study, phytoplankton were used to study the sefid ...

estuaries are considered as highly dynamic ecosystem that include the mixing or transition zone between river freshwater and saline water from oceans and seas. estuaries are very important aquatic systems by preserving the coastal biota. flocculation of metals during mixing of freshwater with saline water can be considered as the most important estuarine processes. due to flocculation process, ...

considering the increasing rice consumption in the world and also the excessive application of pesticides to increase production, an experiment was conducted to determine the pesticide residues and their effects on nitrogen, potassium and phosphorus content of hashemi, khazar and gohar (sa13) rice cultivars, in a factorial design at randomized complete block design with three replications. in t...

Anzali International wetland is one of the most valuable water resources as registered in Ramsar convention with an extent of about 150 km2 in the south Caspian Sea. This wetland, not only has ecological and biological importance for migratory birds and rare fish species, but also is used for farms to discharge into the Caspian Sea through this wetland. Therefore its pollution control is very ...

The study of interaction between fish cage culture and sediment population dynamics heterotrophic bacteria in the southern Caspian Sea (Nowshahr region)

Aim . The aim of the study is to analyze current state artificial reproduction Caspian sturgeon and identify problems reducing efficiency ways solve them. Discussion critical sturgeon, which accounts for up 90% world's related resources, concern entire community, due threat extinction these relic individuals on planet. This can be prevented by increasing reproduction. However, natural practical...

Cordylophora caspia, a colonial hydrozoan native to the Ponto-Caspian region, has become a common invader of both fresh and brackish water ecosystems of North America and Europe. We describe 11 polymorphic microsatellite loci for this species. Preliminary analyses indicate that population substructure may contribute to departures from Hardy-Weinberg equilibrium. In addition, new loci failed to ...