Steppe communities of hill massif Saksary (Khakassia)

The Saksary hill massif is situated in the western part of the South-Minusinskaya basin in rain shadow of the Range Abakansky. It is limited by the Abakan river and its affluents the Uybat and the Kamyshta rivers. It extends from west to east by 22 km, from north to south - by 20 km.the climate is ultracontinental. The average annual temperature is about 0°C, a minimal one -48°...-52°C and a maximal one - +34°...39°C. The sum of temperatures above 10°C is 1600°C, the annual amount of precipitation is 250-300 mm. In the western part of Mynusinskaya basins the upper limit of steppe belt is 600 m above s.l. Only the marginal parts of the massif are characterized by heights below 600 m. The basic central part has the heights from 600 to 900 m above s.l. Nevertheless, it is covered with steppe vegetation. At the top part of the northern steep slopes ofseveral highest hills we can only see some trees. The steppe vegetation of the Saksary hill massif in outline was characterized by V.V. Reverdatto (1928), A.V. Polozhyi and A.T. Maltseva (1974). The principal aims of this work are to reveal the diversity of steppe communities of the Saksary hill massif, to classify them according to the principals of Braun-Blanquet classification and to describe the structure of vegetation cover. The diversity of the Saksary hill massif steppe communities is presented with 5 variants and 5 subassociations of 7 associations belonging to Central Asian class Cleisto-genetea squarrosa and European Siberian class Festuco-Brometea The altitude above the sea level, steepness and stoniness of hill slopes determine the pattern of steppe associations. The Saksary hill massif has three altitudinal steps: 1) the pediment of hill massif (350-450 m above s.l.); the foot, marginal part of hill massif (450-600 m above s.l.); 3) the top, central part of hill massif (600-900 m above s.l.). The first hill massif step is characterized by predominance of flat surfaces, the second one - with gentle slopes (3-7°) and the third - with mean (7-15°) slopes. The steep slopes (15-25°) are present on the third hill massif step and more rarely on the second one. The altitudinal-belt steppe types cover the gentle (3-7°) and mean (7-15°) slopes. They succeed one another as the altitude increases. On the hill massif pediment bunchgrass steppes of subass. Artemisio frigidae-Stipetum krylovii artemisietosum scopariae predominate. On the foot part of hill massif (450-600 m above s.l.) they give place to bunchgrass steppes of ass. Thalictro foetidi-Festucetum valesiacae, above 600 м gentle slopes and sun exposed mean slopes are covered with tussock steppes of ass. Artemisio glaucae-Caricetum pediformis, on shadowed slopes the meadow steppes of ass. Bupleuro multinervi-Helictotrichetum desertorum predominate. The steep slopes (15-25°) are covered with crushed stones and have the shape of stairs, their pattern of steppe communities is the same on its all altitudinal range. The crushed stone «steps» are covered with short grass petrophytic steppes of ass. Androsaco dasy-phyllae-Caricetum pediformis, on the steep parts of stony slopes tussock petrophytic steppes of ass. Youngio tenuifoliae-Helictotrichetum desertorum predominate. The steppe communities of the first and the second hill massif step belong to the class Cleis-togenetea squarrosae and the third one - to the class Festuco Brometea.

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