Heydari Wildlife Refuge (HWR) is located in Binalood mountain range of the Razavi Khorassan Province in Northeastern Iran. The area belongs to the central part of Khorassan-Kopet Dagh floristic province, which is a transitional zone between different phytogeographical units in the Irano-Turanian region. We investigated the floristic composition, life-form spectrum and the phytogeography of the area during 2014-2017 by collecting vascular plants and establishing 443 random-quadrats in representative stands of different vegetation types. A total of 588 vascular plant taxa (species and subspecies) belonging to 304 genera and 65 families are recorded as native and naturalized in the study area. The richest plant families are Asteraceae (40 genera/87 species), Fabaceae (15/72), Poaceae (33/60), Brassicaceae (33/49), Lamiaceae (19/32), and Apiaceae (18/27). The genera Astragalus (44 species), Cousinia (17), and Allium (10) are the richest ones. However, the dominant canopy cover belongs to Acantholimon, Astragalus, Artemisia, and Acanthophyllum species. Raunkiaer's plant life-form spectrum in the area is dominated by hemicryptophytes (41.50%) and therophytes (28.06%). The core flora of HWR has the Irano-Turanian origin; the widespread elements are also well represented in the study area. Based on the Sørensen dissimilarity index, the HWR has about 50% dissimilarity to the adjacent areas. The study area is inhabited by several Iranian and/or Khorassan-Kopet Dagh endemic (19%), threatened (16%), and narrow-range plant species. The results indicate the importance of the HWR in the plant diversity of NE Iran.

The xerophilic woodlands of wild pistachio Pistacia vera L. remnants occur as several isolated stands in Central Asia. The Kopet Dagh mountain range, northeastern Iran, is the westernmost distribution range of wild pistachio. In this research, we present the annotated checklist of vascular plants of two remnants of P. vera woodlands along the Iran–Turkmenistan borders. We provide the life‐forms, phytogeographical spectrum, endemism and conservation status of the flora. The field surveys were conducted through several field collection efforts during 2018–2020. A map showing the boundaries of the woodlands was prepared. We recorded 348 plant species distributed in 214 genera and 48 families. The richest families were Asteraceae (33 genera with 59 species), Poaceae (22 with 41), Brassicaceae (24 with 28) and Fabaceae (11 with 27), and the two richest genera were Astragalus (ten species) and Galium (nine species). The dominant life‐forms were therophytes (54%) and hemicryptophytes (24%), which confirm a xeric climate condition. Irano–Turanian elements (195 species, 56%) were the most common plants, followed by bi‐regional (21%) elements. Based on our samplings, the Khorassan‐Kopet Dagh endemics represented only four percent of the flora. We recorded 34 endemics/sub‐endemics of plants, eight of which were categorized as threatened or near‐threatened. The results indicated the important role of pistachio remnant woodlands in plant biodiversity and conservation biogeography of northeastern Iran.

In grazing conditions, unpalatable species may induce either associational defense or neighbor contrast susceptibility in neighboring communities. Using surveys from eight grasslands, we tested whether various unpalatable species have the same impacts on neighboring communities in response to grazing. The studied unpalatable species were: Phlomis cancellata (an unpalatable nonpoisonous plant), Euphorbia boissieriana, E.microsciadia (poisonous plants), and Seseli transcaucasicum (a highly poisonous plant). Our results showed that, in the ungrazed grasslands, communities containing P. cancellata had lower biodiversity than communities without it. In the moderately- and heavily grazed grasslands, P. cancellata induced associational defense in the neighboring communities. In heavily grazed grasslands, both Euphorbia species promoted neighbor contrast susceptibility in the neighboring communities. Similarly, S. transcaucasicum in a heavily grazed grassland, induced neighbor contrast susceptibility. Different responses of plant community vulnerability among the studied unpalatable plants might be due to herbivore different foraging decisions. Accordingly, grazers selectively choose from other patches when facing P. cancellata and other plant individuals when there is a poisonous plant in a patch. Our results suggested that grazing intensity may not substantially affect the foraging decisions of sheep and goats in response to unpalatable species. We recommend monitoring the abundance of poisonous species to maintain the sustainable use of grasslands.

Halimocnemis commixta is recorded as a new species for the flora of Iran from Pistacia vera woodland remnants in NE Iran. It grows on open salty soils with several typical halophytic plants. The new species record is illustrated and compared with the closely related species. It can be distinguished from H. gamocarpa by its clustered flowers and irregularly horned fruits and differs from H. pilosa by its entirely short and adpressed hairs. We provide some additional notes on the distribution, ecology, and conservation status of the newly recorded species.

Urban vacant lots (VLs) can harbour a large number of rare and endangered species.In the present study, we evaluated species composition and biodiversity of plant communities inhabiting VLs in the City of Mashhad, northeastern Iran. We used a line transect sampling method to sample 98 random VLs along different districts of the City. We classified VLs based on their species composition and environmental factors. Then, a significant difference in the community composition along with the dominant and indicator species of clusters was evaluated. Also, we compared species and phylogenetic diversities of clusters. We identified four clusters. The species composition of the four clusters was different. One cluster (i.e., D912) had more rangerestricted species than the other clusters. This cluster also had a higher species and phylogenetic diversity than the others. Two clusters had the lowest phylogenetic diversity in comparison with the others. Our results implied that income distribution in the city had indirect effects on plant communities of VLs. Vegetation of VLs in areas with higher average income was less damaged than that of the lower-income areas. Because of its most diverse and range-restricted plants, the D912 cluster should be managed to maintain the biodiversity in the city. Land use change to parks or urban agricultural lands is suggested for degraded and species-poor VLs.