Jalil Noroozi

Alpine cushion plants inhibit the loss of phylogenetic diversity in severe environments

Biotic interactions can shape phylogenetic community structure (PCS). However, we do not know how the asymmetric effects of foundation species on communities extend to effects on PCS. We assessed PCS of alpine plant communities around the world, both within cushion plant foundation species and adjacent open ground, and compared the effects of foundation species and climate on alpha (within-microsite), beta (between open and cushion) and gamma (open and cushion combined) PCS. In the open, alpha PCS shifted from highly related to distantly related with increasing potential productivity. However, we found no relationship between gamma PCS and climate, due to divergence in phylogenetic composition between cushion and open sub-communities in severe environments, as demonstrated by increasing phylo-beta diversity. Thus, foundation species functioned as micro-refugia by facilitating less stress-tolerant lineages in severe environments, erasing a global productivity - phylogenetic diversity relationship that would go undetected without accounting for this important biotic interaction.

Phytosociological and ecological study of the high alpine vegetation of Tuchal Mountains (Central Alborz, Iran)

The present paper deals with the phytosociology and ecology of the high alpine zone of Tuchal Mts. (Central Alborz). On the basis of 185 phytosociological relevés, the vegetation of high alpine snow-beds, fellfi elds and xerophytic habitats of Tuchal Mts. is analysed. By means of phytosociological classifi cation and ordination (Detrended Correspondence Analysis), the plant communities and environmental factors governing the variance in vegetation are described and discussed. The studied plant communities are arranged in two provisional orders, four alliances (Taraxaco brevirostr is-Polygonion serpyllacei , Astragal ion iodotropidis , Cousinion mult i lobae and Acantholimion demawendici) and 13 associations (Polygonetum serpyllacei , Ranunculetum crymophil i , Trifol ietum radicosi , Astragaletum iodotropidis , Galio decumbentis-Thymetum pubescentis , Vicietum ciceroideae, Rumicetum elbursensis , Bufonio kotschyanae-Cousinietum mult i lobae prov., Hordeo violacei-Cousinietum mult i lobae prov., Astragalo chrysanthi-Cousinietum mult i lobae prov., Oxytropido persicae-Cousinietum mult i lobae, Acantholimetum demawendici and Jurinel letum frigidae). The communities of these habitats strongly depend upon the duration of snowcover. Edaphic and hydrological quality of micro-sites is more important for the species composition and vegetation mosaic than the regional climatic gradient. About 90% of the species of the study area are Irano-Turanian elements. All syntaxa are further characterized by life form spectra. Flowering phenology of seven associations was studied according to the snowmelt gradient.

Endemism in Mainland Regions – Case Studies

Vascular plant endemism of different mainland regions in relation to ecological conditions and habitats is analysed in detail. The regions belong to different biogeographical zones, climates and are of different sizes. Because of their species richness, level of endemism, and a long history of human occupation affecting the biota, some of the regions are partly or completely located in Biodiversity Hotspots.

A new alpine species and a new record of Astragalus sect. Stereothrix (Fabaceae) from Iran, with comments on the phytogeography of the section

Abstract Mahmoodi M., Maassoumi A. A. & Noroozi J.: A new alpine species and a new record of Astragalus sect. Stereothrix (Fabaceae) from Iran, with comments on the phytogeography of the section. — Willdenowia 43: 263–270. December 2013. — ISSN 0511-9618;