Search results for " Asia"
showing 10 items of 299 documents
Dwarf shrub vegetation of rock ledges and clefts in the Pamir Alai Mountains (Middle Asia: Tajikistan)
2016
AbstractThe paper presents the results of phytosociological researches on rocky slope vegetation in Tajikistan with the aim to establish a comprehensive syntaxonomical classification system. Field studies were conducted in 2010-2014 in Pamir Alai ranges and Pamirian plateau. Nearly 500 relevés documenting rock and scree vegetation were made according to the Braun-Blanquet method. Numerical analyses of selected 58 relevés representing dwarf shrub vegetation on rock ledges made it possible to distinguish: Ephedro glaucae- Spiraeion baldschuanicae and Ephedrion regeliano-fedtschenkoi alliances, as well as Spiraeetum baldschuanicae, Rhamnetum coriaceae, Pentaphylloidetum parvifoliae and Pentaph…
Vegetation of Middle Asia – the project state of art after ten years of survey and future perspectives
2017
Middle Asia is one of the most diverse regions on earth with high endemism of vascular plants and remarkable habitat richness, mainly due to the considerable altitudinal range (300-7,500 m a.s.l.). The region is considered as one of the 34 global biodiversity hotspots. This paper presents the Vegetation of Middle Asia database (VMA; GIVD ID: AS-00-003; http://www.givd.info/ID/AS-00-003) which is the regional database that covers the area of Tajikistan, Kyrgyzstan and Uzbekistan. The database contains phytosociological relevés collected between the years 2006 and 2016 in different vegetation types with the use of the Braun-Blanquet method. The covered vegetation types include: deciduous fore…
Late Cretaceous-Early Eocene origin of yams (Dioscorea, Dioscoreaceae) in the Laurasian Palaearctic and their subsequent Oligocene-Miocene diversific…
2015
Aim: Dioscorea (Dioscoreaceae) is a predominantly pantropical genus (< 600 species) that includes the third most important tropical tuber crop and species of pharmacological value. Fossil records from both the Northern and Southern Hemispheres were used to test hypotheses about the origin of the genus Dioscorea, and to examine potential macroevolutionary processes that led to its current distribution. Location: Pantropical distribution. Methods: Divergence times were estimated using the most comprehensive phylogeny of the group published to date based on plastid sequences and fossil calibrations, applying a relaxed-clock model approach. Ancestral areas and range shifts were reconstructed us…
Vegetation of feather grass steppes in the western Pamir Alai Mountains (Tajikistan, Middle Asia)
2016
Aims: To propose the first syntaxonomical scheme for the graminoid steppe vegetation of the montane and alpine zones in the Pamir-Alai Mts. in Tajikistan with some remarks on its environmental gradients. Location: Tajikistan. Methods: A total of 155 relevés were sampled in 2015 using the seven-degree cover-abundance scale of Braun-Blanquet and subsequently 148 of these relevés were selected and classified by the modified TWINSPAN method using the four step interval scale with cutoff levels of 0%, 5%, 10% and 25% and total inertia as a measure of cluster heterogeneity. Diagnostic species were identified using the phi coefficient as a fidelity measure. The detrended correspondance analysis wa…
Two new varieties in Stipa (Poaceae) from Central Asia
2016
Abstract The paper presents descriptions of two new taxa, Stipa ×brevicallosa var. hissarensis and Stipa orientalis var. ladakhorum. Both of them differ from the nominal varieties in having densely pubescent (not glabrous or scabrous) leaves of vegetative shoots. First of the above mentioned taxa occurs in Tajikistan (Pamir Alai Mts) whereas the second in India (Western Himalayas). Images of type specimens of both taxa are provided.
First record of Tamarix macrocarpa (Tamaricaceae) for Europe
2017
AbstractTamarix macrocarpa, a species with distribution in Central and North Africa, in the countries bordering the Persian Gulf and in Central and western Asia is recorded for the first time for Europe. Pentamerous flowers and androecium diplostemonous characterize this small tree.
Fen and spring vegetation in western Pamir-Alai Mountains in Tajikistan (Middle Asia)
2016
The paper presents the results of phytosociological research on spring and fen vegetation of the western Pamir-Alai Mountains in Tajikistan. In total, 211 relevés were sampled during field studies conducted in 2008–2013 and 2015 with application of the Braun-Blanquet method. Plant communities of spring heads and peat-accumulated fens inhabiting the high montane and alpine zones in the Zeravshan, Hissar, Hazratishoh, Darvaz, Turkestan and Peter the 1st Mountains are described. A hierarchical syntaxonomic synopsis of spring and fen plant communities in the western Pamir-Alai Mountains is provided. As a result of field investigations and numerical analyses, three fen associations: Caricetum ps…
Syntaxonomy and biogeography of the Irano‐Turanian mires and springs
2021
Aims: To develop the first comprehensive syntaxonomic classification for patchy montane mire and spring vegetation across the Irano-Turanian phytogeographical region in Iran, Tajikistan and Kyrgyzstan and to explore the effects of the main environmental and geographic gradients on their distribution. Location: Alborz Mountain range (Iran), Pamir-Alai Mountains (Tajikistan) and Tian Shan Mountains (Kyrgyzstan); total area of about 3,000,000 km2. Methods: A database of 1,015 vegetation relevés including a total of 675 vascular and bryophyte taxa was established, covering the large mountains ranges of the Irano-Turanian regions in Iran, Tajikistan and Kyrgyzstan, at altitude ranging from 1,300…
Multivariate morphometric analysis of the Stipa turkestanica group (Poaceae: Stipa sect. Stipa)
2015
Based on numerical analyses of macromorphological characters (cluster analysis, principal coordinate analysis and principal component analysis), scanning electron microscopy observation of lemma and lamina micromorphology, as well as field observations, five taxa belonging to the Stipa turkestanica group have been recognized in the mountain area of Central Asia. They are S. turkestanica subsp. turkestanica, S. turkestanica subsp. trichoides, S. macroglossa subsp. macroglossa, S. macroglossa subsp. kazachstanica and S. kirghisorum. As a result of this study, we propose one new combination, S. macroglossa var. pubescens, and designate lectotypes for S. turkestanica subsp. trichoides and S. ma…
Stipa ×fallax (Poaceae: Pooideae: Stipeae), a new natural hybrid from Tajikistan, and a new combination in Stipa drobovii
2017
Stipa ×fallax nothosp. nov . (Poaceae), from western Pamir Alai Mts (Tajikistan), is described and illustrated. Field observation, numerical analyses of morphology, and pollen grain viability data show that it originated from hybridization between S. drobovii and S. macroglossa subsp. macroglossa , species representing sections Smirnovia and Stipa , respectively. Stipa ×fallax is morphologically close to S. ×alaica and S. ×hissarica , but is distinguished by its shortly pilose lower part of the awn and densely pubescent leaves. Characters distinguishing S. ×fallax from its parental species as well as similar hybrid taxa in section Smirnovia that also grow in Central Asia are presented. The …