Pastoral systems are characterised by a number of features that are absent in arable cropping systems. These features include: (i) pastures are biologically diverse so interactions between plant species must be considered; (ii) economic return requires the inclusion of the animal as an additional trophic level; (iii) interaction between the grazing animal and the pasture is complex, influenced ...

1. A potential driver of species abundance that remains understudied is the interaction between host species and their microbial symbionts. Beneficial symbionts could promote the dominance of common host species by increasing their population growth rates more than they do for rare species, and symbiont benefits could be important for maintaining rare species in communities. Alternatively, intr...

During ROPME Winter Cruise 2006, twenty six surface sediment samples taken from the Northwestern part of the Persian Gulf at depths of 13-77m were analyzed for their foraminifera content. A total of 93 species of benthic foraminifera were found in the study area. The foraminifera assemblages were dominated by Ammonia beccarii, Spiroloculina excavata, S. depressa, Quinqueloculina dimidiata,...

During an investigation on pteridophytes (ferns) of Guilan province (N Iran), 402 specimens were studied. Of these, 44 species, under 21 genera, belonging to 13 families, were identified. Based on the approved instruction given by the "International Union for the Conservation of Nature and Natural Resources (IUCN)", after performing the filtering stage, 17 species were identified as endangered...