The paper focuses on identifying features of natural reforestation after abandonment of agricultural land. To this end, within the most agrarian-developed areas of the Tunkinskaya depression (Republic of Buryatia) during the annual monitoring observations of 2014–2018 considered the current state of 22 sites of fallow land. The geobotanical analysis of the species composition of woody and grass covers of fallow lands was carried out. The main options for overgrowing fallow lands were determined. It is recovery through birch, pine or mixed undergrowth, as well as meadow succession. Natural reforestation on fallow lands flows more intensively around the perimeter of the fields. The species composition of the undergrowth is identical to the forest canopy of the adjacent forests. In the grass cover of fallow lands in most cases there is a dominance of meadow species. In the grass cover of the surrounding forests, forest species are prevail. In the course of the research, the dependence of the intensity of the spread of tree undergrowth on the degree of remoteness from the forests surrounding the abandoned lands was confirmed. A decrease in overgrowth of tree species was observed as the distance from the periphery of the deposit to its center increased. The main factor complicating the process of reforestation is grazing cattle. Its termination contributes to the intensive appearance of woody shoots.

Atutova Zhanna Vladimirovna, Candidate of Sciences (Geography), Senior Research Scientist, V. B. Sochava Institute of Geography SB RAS, 1, Ulan-Batorskaya st., Irkutsk, 664033, Russian Federation, tel.: (3952) 42-64-22, e-mail: atutova@mail.ru 

Yekimovskaya Olga Afanasievna, Candidate of Sciences (Geography), Research Scientist, Baikal Institute of Nature Management SB RAS, 8, Sakhyanova st., Ulan-Ude, 660047, Russian Federation, tel.: (3012) 43-36-76, e-mail: oafe@mail.ru

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