growth and productivity of plants are mainly affected by various environmentalfactors in different ecosystems and natural habitat in the world. this research aims to studythe existing relationships between the phytosociology characteristics of thymuskotschyanus and environmental factors in order to find the most important factorsgoverning development of the species in middle taleghan rangelands...

Preservation of ecosystems requires an understanding of the ecosystem processes that regulate ecosystem resources. Patches and inter-patch features are parts of the ecosystem that are partially responsible for effects on transporting and storing materials in the ecosystem. The structural features of ecological patches including size, number and the average inter-patch length are important becau...

in taleghan, olivine basalt-basaltic andesite dykes as part of tertiary mamgmatic activities in central and western alborz zone, intruded into both karaj formation and late eocene-oligocene volcanic rocks. these dykes have similar geochemical characteristic which suggest that they are originated from a common source. on the primitive mantle normalized spider diagram, the dykes are characterized...

the relationship between some habitat factors and fish assemblage was analyzed in the taleghan river, alborz province, iran. fish specimens from thirty-three sites were sampled by electrofishing device in october 2014. the habitat parameters, including elevation (m), water depth (cm), river width (m), river slope (%), current velocity (m.s-1), number of large stone (> 15 cm), average stone diam...

the geometric morphometrics method was applied to study the morphological differences in 95 specimens of kura barbel (barbus lacerta, heckel 1834) collected from three riverine ecosystems of the sefidrud basin, viz. taleghan, totkabon and kloraz rivers.  for this purpose, the left sides of the specimens were photographed. then, 14 landmark-points were defined and digitized on 2d pictures using ...

today water supply issue in large cities seems to be a big problem. this becomes more important with population growth and urbanization extension. to cope with this problem lots of irrigation and drainage projects have been implemented and operated that subsequently many socio- economic and cultural effects have been brought to the areas . the objective of the present study is to survey the soc...