Practice of Geobotanical Indication of Forest Growth Conditions in the Steppe and Wooded Steppe Ecotone in Central Mongolia

The forest conditions in the Central Aimag of Mongolia, located in the southern part of the Baikal catchment area, near the southern border of the forest-steppe subzone, were examined within the framework of this study. The field materials collected in the summer 201–2018 at the Zuunmod Model polygon serve as the core of the study. An ecosystem map of the Model polygon with the scale 1:50 000 and the Key plot with the scale 1:5 000 was drawn up using World Viеw-2 satellite imagery data (2016). The proven method of botanical indication of forest growth conditions is as follows: identification of the ecologic and coenotic groups of plant species, calculation of the moisture coefficient based on the ratio of the number of species included in the groups characterizing the extreme conditions of the moisture gradient and distribution of communities in accordance with the values of the gradient in the ecological series. Communities of stages of ecological series serve as indirect indicators of the forest conditions: Stage I: Кu <1, insufficient humifying for tree growth, Stage II: Кu 1–2, average humifying, Stage III: Кu >2, sufficient humifying for tree growth. The stages also correspond to the landscape conditions and the character of the vegetation cover.