Search results for "Middle Asia"
showing 10 items of 29 documents
Distribution, floristic structure and habitat requirements of the riparian forest community Populetum talassicae ass. nova in the Central Pamir-Alai …
2013
This paper discusses the floristic structure, distribution and habitat requirements of a new forest syntaxon, <em>Populetum talassicae </em>ass. nova. The potential range of the <em>Populetum talassicae </em>association comprises the central Pamir-Alai and Tian-Shan Mountains in Middle Asia. The biotope of this community comprises high mountain river valleys and shore zones of mountain lakes situ- ated at elevations between 2200 and 2750 m. Phytocoenoses of the <em>Populetum talassicae </em>association are characterized by a clear predominance in the tree layer of a characteristic species of the association ‒ <em>Populus talassica</em>. Shrubs…
Syntaxonomy, diversity and distribution of the vegetation of rock crevices, clefts and ledges in the colline and montane belts of Central Pamir-Alai …
2021
Mountain areas are very often considered to be biodiversity hotspots. Rocks are one of the most unique habitats and serve as a suitable biotope for many endemic and specialized plant species. Here we present the results of the vegetation studies conducted in central and eastern Pamir-Alai and the south-western Tian Shan mountains in 2013‒2019. Based on 334 phytosociological relevés we propose a synopsis of the rock communities of the montane and colline zones of eastern Middle Asia. As a result of our research, we distinguish 17 communities defined into five groups of petrophytic vegetation within the Caricion koshewnikowii alliance. We describe 11 new associations: Feruletum bucharicae, Sc…
Caucalido platycarpi-Vicietum michauxii — a new weed association from crop fields of Kyrgyzstan (Middle Asia)
2014
Abstract The study presents the results of geobotanical investigations conducted in crop fields in the western Tian Shan Mts in Kyrgyzstan (Middle Asia). The main research focused on classification of weed communities developing within this poorly investigated area, were conducted in the vicinity of Bishkek and Kara-Balta in 2010. Altogether, 299 phytosociological relevés were sampled using the Braun-Blanquet method. Based on all segetal vegetation patches, the analyses distinguished a new association: Caucalido platycarpi-Vicietum michauxii. The results of these phytosociological studies fill a gap in the knowledge about the syntaxonomical diversity of the Middle Asia region, which is one …
A report on the conservation status of segetal weeds in Tajikistan
2014
Summary Intensification of agriculture has significantly diminished the populations of segetal weeds worldwide in recent decades. Remarkable changes to the entire flora and vegetation of man-made habitats are being observed in agroecosystems. The present study analyses, for the first time, the threat status of segetal weeds in Tajikistan. A group of 871 weed species were evaluated against IUCN criteria. The assessment of threat status revealed that 214 weed taxa have to be regarded as threatened in Tajikistan, including 18 endemic and four subendemic plants. Five species have been classified as extinct, 27 as critically endangered, 27 as endangered, 39 as vulnerable, 34 as near threatened a…
Populetum pamiricae ass. nova – an endemic forest association to Pamir in Tajikistan (Middle Asia)
2015
Abstract The floristic structure, distribution and habitat requirements of a forest syntaxon, Populetum pamiricae ass. nova is described. The potential range of the Populetum pamiricae association comprises the mountains of eastern Tajikistan (Pamir Alai Mts), Kashgaria in western China (Kunlun Shan Mts) and north-eastern Afghanistan (Hindu Kush Mts) in Middle Asia. The biotope of this community comprises of high mountain river valleys situated at elevations between 2,500 and 3,200 m above sea level. Phytocoenoses of the Populetum pamiricae association are characterized by the apparent domination in the tree layer of a diagnostic species, Populus pamirica. The tree stand has a mean cover ar…
Stipa zeravshanicasp. nov. (Poaceae), an endemic species from rocky walls of the western Pamir Alai Mountains (middle Asia)
2013
Stipa zeravshanica M. Nobis sp. nov. from the western Pamir Alai Mts (Tajikistan) is described and illustrated. Morphologically, the new species is similar to S. gracilis, but it is easily distinguishable by pilose (vs. glabrous) lower part of the awn, and generally somewhat longer ligules of the vegetative shoots. Epidermal patterns of the lemma in S. zeravshanica and three other closely related taxa, namely S. gracilis, S. himalaica and S. orientalis, were examined by means of SEM. The main macro-morphological and micro-morphological characteristics differentiating all mentioned species are presented. Additionally, a lectotype for S. gracilis is designated. Based on phytosociological rele…
Syntaxonomy and ecology of thermophilous deciduous open woodlands and scrub vegetation in Tajikistan (Middle Asia)
2022
In this paper we present the first syntaxonomic classification for the thermophilous open wood and scrub vegetation in Tajikistan with some remarks on its environmental gradients. Altogether 143 relevés were sampled between 2014–2021 using the seven-degree cover-abundance scale of Braun-Blanquet. They were classified by the modified TWINSPAN method with the use of the four step interval scale with cutoff levels of 0%, 2%, 5% and 10% and total inertia as a measure of cluster heterogeneity. Diagnostic species were identified using the phi coefficient as a fidelity measure. Detrended Correspondence Analysis was used to determine the relation between samples, vegetation units and the major grad…
Pseudosteppes and related grassland vegetation in the Pamir-Alai and western Tian Shan Mts – the borderland of the Irano-Turanian and Euro-Siberian r…
2020
The aim of our study was to complete the syntaxonomical scheme for grassland vegetation of the lowland, montane and alpine zones in the Pamir-Alai and western Tian Shan Mts in Tajikistan and Kyrgyzstan with some remarks on its environmental predictors. A total of 198 relevés were sampled in 2013–2018 using the seven-degree cover-abundance scale of the Braun-Blanquet approach. They were classified with k-means algorithm with tranforming cover values to three level scale of the following intervals 0%, 5% and 25% and total inertia as a measure of cluster heterogeneity. Diagnostic species were identified using the phi coefficient as a fidelity measure. Non-metric Multidimensional Scaling (NMDS)…
Halophytic vegetation and adjoining plant communities in Middle Asia (Pamir-Alai and western Tian Shan)
2021
In this paper, we complete the syntaxonomical scheme for halophytic vegetation and adjoining plant communities of the lowland, montane and alpine zones in the Pamir-Alai and western Tian Shan in Tajikistan and Kyrgyzstan with some remarks on its environmental predictors. A total of 217 relevés were sampled in 2014–2019 using the seven-degree cover-abundance scale of the Braun-Blanquet approach. Modified TWlNSPAN was used to classify plant communities based on species composition. The cover-abundance scale was transformed using the four-step interval scale with cut-off levels at 0%, 5% and 25%. Diagnostic species were identified using the phi coefficient as a fidelity measure. Non-metric Mul…
Vegetation of rock crevices of the montane and colline zones in the Pamir-Alai and Tian Shan Mts in Tajikistan (Middle Asia)
2014
The paper presents the results of phytosociological research conducted on the vegetation of rock habitats in the montane and colline zones of the Pamir-Alai Mountains (Tajikistan). During field surveys done in 2010–2013, 122 phytosociological releves were sampled. Plant species were recorded according to the Braun-Blanquet cover-abundance scale. The vegetation studies were carried out generally in the western Pamir-Alai and south-western Tian Shan Mts, especially in the Zeravshan, Hissar, Hazratishoh, Darvaz, Rushan, Turkestan, Kuramin and Vanch ranges. A synopsis of the rock communities of the montane and colline zones in Tajikistan is proposed. The collected material presents most of the …