DEMOGRAPHIC STRUCTURE AND POPULATION SIZE OF RARE ENDEMIC OXYTROPIS SPECIES FROM PRIOL’KHONYE STEPPE
I.Yu. Selyutina1, D.V. Sandanov2
1Central Siberian Botanical Garden, SB RAS, 630090, Novosibirsk, Zolotodolinskaya str., 101 selyutina.inessa@mail.ru 2Institute of General and Experimental Biology, SB RAS, 670047, Ulan-Ude, Sakh’yanovoi str., 6 sdenis1178@mail.ru
Keywords: охрана растений, редкие виды, эндемики, Oxytropis triphylla, O. microphylla, O. popoviana, O. peschkovae, демография, Приольхонье, plant conservation, endangered species, endemic, Oxytropis triphylla, O. microphylla, O. popoviana, O. peschkovae, demography, Priol’khonye
Abstract
Demography and condition of rare and endemic Oxytropis species in Priol’khonye steppes have been studied. Most of the studied populations are complete, definitive, normal, mature with monomodal or bimodal left -sided ontogenic spectra. The analysis of the cenopopulations state showed that moderate grazing does not aff ect them. Under overgrazing ontogenic spectrum is usually right-handed, cenopopulations become not complete, density of individuals decrease, and declining populations acquire other regressive features. It can be concluded that all studied Oxytropis species are vulnerable because of the small size of their populations. One of the main reasons, in addition to a sharp decline of population size due to demographic fluctuations and natural disasters, is the emergence of a number of genetic problems caused by the loss of genetic diversity, inbreeding and genetic drift . In this connection it is necessary to study the genetic diversity of rare endemic Oxytropis species and implement the regular monitoring of their populations.
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