ТРАНСФОРМИРУЕМЫЕ АРИДНЫЕ ЭКОСИСТЕМЫ АРМЕНИИ
ENDANGERED ARID ECOSYSTEMS OF ARMENIA
С.Г.Нанагюлян, Ф.Д.Даниелян, М.С.Аракелян, А.С.Казарян, Л.В.Маркарян
S.G.Nanagulyan, F.D.Danielyan, M.S.Arakelyan, A.S.Ghazaryan, L.V. Margaryan
Факультет биологии, Ереванский государственный университет
(ул. А.Манукяна 1, Ереван, 0025, Армения)
Faculty of Biology, Yerevan State University
e-mail: snanagulyan@ysu.am
Приводятся данные о биоразнообразии грибов, растений и животных аридных экосистем Армении (полупустыни с участками пустынь и сухие степи), которые находятся под антропогенным прессом и нуждаются в природоохранных мероприятиях.
The biodiversity of fungi, plants and animals of arid ecosystems of Armenia (semi-desert with sites of desert and dry steppes) under anthropogenic transformation and call to conservation measures.
Armenia is located in Southern Transcaucasia which is in South Caucasus, on a joint of Caucasus with Middle Asia, and occupies a part of the extensive Armenian plateau. It is a landlocked country between Black and Caspian Seas. Armenia is a relatively small (29,743 km2) and typical mountainous country. About 90% of its territory is over 1000 m above sea level, including 40% - over 2000 m.
Relatively recent volcanic activity on the Armenian plateau has resulted in large volcanic formations, and highlands consisting of a series of both small and large mountain massifs. Among four main geographic/geological regions the Ararat Valley represents the lowest part of the Ararat depression (which is still undergoing tectonic movement). This area is covered with alluvial and prolluvial sediments. The average elevation of Ararat Valley is 900 m above sea level and partially semi-desert and dry steppe along the Arax River. The Ararat plain serves as the major agricultural basin for Armenia where more than thirty-five percent of Armenia’s vegetables and fruits are grown.
The arid landscape with poorly known endangered plants and animals species is located in the Arax River Valley in southern west of Armavir region of Armenia. The biodiversity here is rich by rare, endangered and endemic species of flora and fauna, due to their geographic isolation [1, 2]. Out of poor known diversity of ephemeral semi-desert vegetation, 23 listed in Red Book of Armenia (1990), and 10 species are endemic. Among vertebrates animals 17 species are listed in the Red Book of Armenia [5, 6] and 8 are currently entered in the IUCN Red List (3 of them are listed as CR - critical endangered) species when the invertebrate fauna from this site is almost unknown. The data about fungi diversity here are almost absent [4].
Among the following distinct types of vertical landscape zones on the territory of Armenia semi-desert with fragments of desert, mountainous steppe, forest, alpine and nival the arid ecosystems are most endangered. Azonal and wetland zones are separated. A semi-desert belt in Armenia is located on the range of 400 to 1300 m above the sea level and occupies the area of 4550 km. The semi-desert zone often penetrate to neighboring types of zones along the valley of Kasakh, Hrazdan, Azat, Vedi, and Arpa rivers. Within the boundaries of the belt the vegetation is presented by xerophyte communities, which apply to the desert and semi-desert vegetation, and by intrazonal groups. The deserts with extremely arid climatic conditions and scare vegetation cover (up to 30%) are found in the Ararat valley and presented by:
1) psammophytic desert formation (attached to sandy soils) characterized by Caligonium polygonoides, Achillea tenuifolia, Salsola tamamschiani vegetation and other species of psammophytic plants. Only few species of fungi were founded in this formation. The biota of fungi consists mostly of agaricoid and gasteroid macromycetes. The best studied desert system is that close to the village of Gorovan. Here is distributed endangered species of lizards Eremias pleskei, Phrynocephalus persicus (Arakelyan et al., 2011) and rodent Meriones dahli.
2) halophytic desert formation (attached to soils rich in salts and minerals) characterized by Salsola ericodes, S. dendroides, S. nitraria, Halostachus caspica, Halocnemum spp. and Sueda spp. and additional more than 200 halophytic species of plants communities, could be found in little isles among semi-desert zone on Ararat plain (Ararat, Armavir regions);
3) gypsophytic (attached to soils rich in gypsum) characterized by Gypsophila aretioides, G. bicolor, Lactuca takhtadzhianii, and Gundolia spp. and about 300 species of plants.
In halophytic and gypsophytic desert the species of lizards and snakes are scanty: Lacerta strigata often occur in mesophilic parts of desert, and Natrix natrix and Natrix tessellata meets near water reservoir. The Bufo viridis is single amphibian species found in especially dry places.
Semi-desert habitat is characteristic of the dry and rocky lowlands of the Ararat valley, Zangezur mountain range, Meghri, and Vaik regions at middle flow of Arax and its foothills, at altitudes of 900 to 1500 m. The vegetation consists mostly of ephemeral plants, such as Artemisia fragrans, Capparis spinosa, Kochia prostrata, and Poa bulbosa with particularly rich floristic composition, with 437 plant species. Semi-deserts are the original habitat of several important wild ancestors of domestic crops.
Among vertebrates, reptiles are more abundant in semi-desert zone. Near 30 species of reptiles, about 25 small mammals are habitats in this zone. The most characteristic species of reptiles for semi-desert zone are: Testudo graeca and Mauremys caspica turtles, Eremias strauchi, Trachylepis septemtaeniata, Eumeces schneideri lizards, Typhlops vermicularis, Malpolon monspessulanus, Eryx jaculus, Macrovipera lebetina snakes. Among amphibian species in semi-desert zone the most often meet Bufo viridis, rarely Hyla savignyi and in some places Pelobates syriacus. The common species of birds are: Falco subbuteo, F. naumanni, F. tinnuncilusm, Oenanthe deserti, Corvus monedula, Sitta tephronota, Sylvia hortensis, S. mystacea. Among small mammals (Rodentia, Insectivora, Chiroptera) species in semi-desert zone meet Rhinolophus ferrumequinum, Rh. mehely, Myotis blythi, M. shaubi, M aurascense, M. mystacinus, M. emarginatus, Pipistrellus kuhli, P. pipistrellus, Vespertilio murinus, Eptesicus bottae, Hemiechinus auritus, Erinaceus concolor, Microtus arvalis, Silvaemus ponticus, Meles meles, Martes foina.
Dry mountainous steppe subzone represents a transitional zone from semi-deserts to mountainous steppe. It includes steppes in north-eastern areas of the Republic up to 900 meters, as well as those in the Arax depression in the south up to 1700-1800 meters. Mountain dry vegetation is hardly visible among rocks, being characterized by very small and inconspicuous plants. The topsoil is almost absent so that these areas are often defined mountainous deserts or frigana. Vegetation is mostly formed of grasses and dwarf bushes, with small leaves and pillow-like shape. The most typical vegetation are Astragalus sp., Acantholimon sp. and other thornbushes. A wide range of soils present here. The most species of found fungi were grown on wood remnants, died branches in gardens, meadows and pastures. Several species of fungi have the narrow specialization. Among 60 species of registered fungi 6 taxa are included in the Red Book of Armenia. Battarrea phalloides from gasteromycetes identified as Extent species. According to paleontological data it is belongs to the relict species of Cretaceous period. Other species included in Red Book as Critically endangered (Haploporus odorus), Endangered (Volvariella bombycina), and Vulnerable (Helvella atra, Montagnea arenaria, Podaxis pistillaris).
The dry mountain steppe is usual habitat for reptiles. Lacerta media, Eremias strauchi, Trachylepis septemtaeniata, Eumeces schneideri, Ophisops elegans are penetrating to this zone from semi-desert. Ablepharus bivittatus is typical for dry mountain steppe. Among snakes usually meet Typhlops vermicularis, Eirenis punctatolineatus, Eirenis collaris, Platyceps najadum, Hierophis schmidti, Macrovipera lebetina. Here is distributed the unique examples of vulnerable species of endangered fungi Podaxis pistillaris, which fruitbodies are discovered only in investigated arid zone of Armenia and belongs to relict species of Cretaceous period.
The natural arid ecosystems are disappearing, being largely converted to agricultural land. Soil of deserts and semi-deserts was managed for cultivation for centuries, but cultivation has required intensive irrigation, and these areas now support fruit, vegetable, flower, and wine production. However, natural habitats in this zone are most threatened due to impacts from human activities. Cultivated lands represent 80 to 90 percent of the area of the semi-desert zone, and natural ecosystems have been extensively damaged as a result of uncontrolled irrigation and agricultural intensification, which has resulted in increased soil erosion, salinity, and pollution.
The result of our inventory and monitoring of arid ecosystems has shown that the biodiversity of Armenia is represented by species which have different origin and most of them have marginal of area of their distribution. Most part of species is from Asia Middle and Mediterranean groups. After glaciations the flora became further dominated by xerophytes, as more arid-zone habitats emerged [3]. It appears that vegetational shifts during the Pliocene were accompanied by the immigration of arid-zone faunas, perhaps from Iran, thus accounting for the unique vertebrate and invertebrate fauna currently found in the Arax Valley. During the glaciations, some relict populations of fauna, flora and fungi in Armenia appear to have survived in forest refugees which were not under ice.
Thus, the biodiversity of arid ecosystems of Armenia is under anthropogenic transformation and call to start a new series of research of biodiversity of region with special attention to threatened, but much neglected and poorly known endemic species of fungi, plants and animals of Ararat Valley.
This study was supported in part by State Committee of Science, Ministry of Education and Science Republic of Armenia (grant N 11-1f 342).
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