drought is transient phenomenon , slow , repetitive and integral part of the climate of each region. drought begins with a substantial reduction in precipitation over the long-term average rainfall and over time, reduced soil moisture and surface and ground water resources will continue to decrease. this phenomenon is the most important in bakhtegan basin because of its importance in strategic ...

The Caspian Sea basin is one of the most important ecosystems in Iran with a high diversity of different aquatic species, so that the issue of determining the taxonomy its fishes has always been considered. Up to now, a total of 297 species of freshwater and brackish fish have been reported from Iran where the subfamily Leuciscinae (minnows) has a high diversity of species in the Caspian Sea ba...

today, the route for economic development in most countries is the same as international open competitive economy. economic institutes well known that supportive public economy belonged on the past and they may compete in the global economy. it is obvious that if they have no competitive potency or not familiar with competition technique, they may be devastated. banking system aims to collect t...

rivers and runoff have always been of interest to human beings. in order to make use of the proper water resources, human societies, industrial and agricultural centers, etc. have usually been established near rivers. as the time goes on, these societies developed, and therefore water resources were extracted more and more. consequently, conditions of water quality of the rivers experienced rap...

the caspian sea contains great resources of oil and gas. the caspian sea is a 700- mile- long body of water in central asia, land located between azerbaijan, iran, kazakhstan, russia and turkmenistan. iran was challenges and opportunities in the caspian region. key question in this thesis includes three section that first question, opportunities of iran in the caspian region, second question ch...

Fish sardines play a key role in the primary chain of production in the sea, and unknowing harvesting of them causes irreparable damage to the marine ecosystem. Also, genetic studies can help preserve biodiversity and take steps to protect the reserves. In this research, the population dynamic of the Amblygaster sirm and it,s the maximum sustainable yield (MSY) were surveyed and calculated and ...