Ecological and cenotic analysis of the cenopopulations of Saposhnikovia divaricata (Turcz. ex Ledeb.) Schischk. (Apiaceae) in the Republic of Buryatia
T. V. ELISAFENKO1, M. V. KAZAKOV1,2, D. G. CHIMITOV3, V. V. TARASKIN2
1Central Siberian Botanical Garden, Siberian Branch of the Russian Academy of Science, Novosibirsk, Russia
2Baikal Institute of Nature Management, Siberian Branch of the Russian Academy of Sciences, Ulan-Ude, Russia
3Institute of General and Experimental Biology, Siberian Branch of the Russian Academy of Sciences, Ulan-Ude, Russia
Keywords: Saposhnikovia divaricata, phytocenotic analysis, coenopopulation, ontogenes, Republic of Buryatia
Abstract
Natural populations of Saposhnikovia divaricata (Turcz. ex Ledeb.) Schischk. has recently been subjected to severe anthropogenic impact due to biologically active substances with a wide spectrum of action detected in plants. The purpose of the study is to determine the state of natural populations of S. divaricata, to identify the biological features of the species that contribute to their stable ststus. 7 cenopopulations in the Republic of Buryatia have been studied, a description of phytocenoses and ontogenetic states of S. divaricata, demographic characteristics of cenopopulations, environmental and biological factors affecting the existence of this species have been identified. S. divaricata has a wide ecological amplitude, grows from tree communities to steppes and deposits. The share of participation in communities does not exceed 2 % of the total projective coverage. Most populations are characterized by a low density of individuals (5-48 individuals/ 100 m2) due to the destruction of plants (root extraction). One stable population without damage was found (density 209 individuals/100 m2) and one recovering population (113 individuals/100 m2). The height of generative plants varies significantly depending on the growing conditions from 35 to 100 cm. Environmental factors that negatively affect the stability of natural populations of S. divaricata have been identified: biotic (massive damage to seeds by invertebrates), anthropogenic (root harvesting, grazing). A number of biological features determine the strategy of the species in nature: a likely low stock of seeds in the soil and a spike in seedlings during dissemination; biological longevity of seeds for more than 5 years; early contractility of roots; dormant buds and renewal buds in the leaf axils of previous years are protected by remnants of leaf sheaths; when the apical bud is damaged, monopodial growth changes to sympodial (more often at the beginning of the virginal ontogenetic state); duration of the pregenerative period 10-12 years; monocarpicity, up to 50 % of generative individuals in the population they form pseudomutches, the percentage of fruit formation in a simple umbrella is 50-100 %.
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