Himalayan Silver Fir (Abies spectabilis) and Birch (Betula utilis) are tree species often found coexisting in sub-alpine forests of the Nepal Himalayas. To assess species-specific growth performances these species, tree-ring samples were collected from subalpine forest Dhorpatan Hunting Reserve, Nepal. Standard ring width chronologies both correlated with climatic variables static running windo...

Abstract Apparent hydrological sensitivity ( η a ), the change in global mean precipitation per degree K of surface warming, is key aspect climate system's response to increasing CO 2 forcing. To determine whether depends on forcing amplitude we analyze idealized experiments over broad range abrupt forcing, from 2× 8× preindustrial values, with two distinct models. We find little between and 4×...

Objective: Yield components and genetic contribution have the most important in final yield and breeding programs of crop plants. For this purpose, 20 varieties of grapevines with Russia origin were evaluated in Urmia and Takestan research station (under full irrigation and drought stress). Methods: Twenty grapevine genotypes were evaluated in Urmia and Takestan research station (under full irr...

a total of 90 species, belonging to 29 genera and 15 families, observed from an urban wetland of meghalaya is the species-rich rotifera assemblage known till date from any sub-tropical ecosystem of the indian sub-region. total richness (s) merits biodiversity value as ~56.0, ~ 38.0 and ~23.0 % of the species recorded from meghalaya, northeast india (nei) and india, respectively while several ro...

The introduction of Registration, Evaluation and Authorisation of Chemicals (REACH), requires companies to register and risk assess all substances produced or imported in volumes of >1 tonne per year. Extrapolation methods which use existing data for estimating the effects of chemicals are attractive to industry, and comparative data are therefore increasingly in demand. Data on natural toxic c...

Background and objectives: Iran owns a rich and prestigious heritage of medicinal herbs but the majority of these plants have not yet undergone chemical, pharmacological and toxicological studies. In the present study some species form northern parts of Iran were evaluated for cytotoxicity. Methods: Sixteen medicinal plants were extracted with methanol and screened for their cytotoxic activitie...

Background & Aim: Drought stress, as a main abiotic stress, has a significant influence on growth and metabolic activities of plant species. In this study, the influence of reduced irrigation on dry herbage, essential oil yield, and chemical components of two thyme species were investigated. Experimental: This study was done in an experimental greenhouse, I.A.U., Shahrekord Branch, Iran at 201...