Phytocoenotic diversity and vegetation mapping of the Zaisan depression, Kazakhstan

Abstract

The paper presents the results of vegetation studies in the Zaisan depression. The middle-scale vegetation map (s. 1 : 500 000) was created. Dominant species of vegetation cover form several ecological-physiognomic vegetation types: psammophytic shrub, psammophytic wormwood, psammophytic grass, perennial saltwort, sagebrush, shrub, saxaul, sagebrush – bunch grass, coniferous forest; floodplain meadow, shrub and woody are characteristic types of river valleys. These types are represented in the map legend. Analysis of the ecological preferences of the dominant species of Zaisan depression revealed the edaphic amplitude of plant species. A large part of dwarf semishrubs (sagebrushes and perennial saltworts) is characterized by wide edaphic amplitude. Shrub Spiraea hypericifolia has also a wide edaphic range. Stipa sareptana is the most ecologically labile species among bunch grasses. Zaisan saxaul is mainly grows on brown and gray-brown soils. The legend to the map is compiled on the base of zonal-typological principle, it contains 35 numbers. 8 numbers of the legend show the homogeneous vegetation, 27 – heterogeneous vegetation. Zonal types of vegetation occupy 64% of the territory (deserts – 32.4%, steppes – 31.6%); intrazonal vegetation – 23.6%. About 17% of the territory is agricultural lands, mostly located in the steppe zone.