Application of Population Model of Siberian Larch for Forest Biodiversity Control in the North of Western Siberia

Abstract

Mechanisms for assessing and predicting the forest resource potential of the northern oil-producing territories of Western Siberia are of great importance in the tasks of environmental impact assessment. The assessment of the biodiversity sustainability of the northern forest areas using predictive population models of tree-edificators (trees as ecosystem engineers), in particular, Siberian larch (Larix sibirica Ledeb) is proposed. A projection matrix was first developed and adjusted to numerical values, and the possibility of its identification is shown based on dynamic curves of the tree stand and cones yield. The variant of ontogenetic stages (juvenile, auxophase, generative) is taken as a basis. A brief description of these stages is given including age limits, duration, and their possible indicators for Siberian larch. Since the duration of the stages is different, the modified Lefkovitch model and indicators of survival, delay and fertility are applied. The first two indicators are identified using the dynamic curve of the normal trees stand (N. V. Vyvodtsev), the third – using the curve of the yield of cones by age as applied to the territory conditions (E. P. Verkhovtsev). As a result, numerical values of parameters of the matrix are obtained, the maximum eigenvalue and an indicator of potential growth are determined, indicating the growth or decline of the population. In the considered variant, their values are close to one, which indicates the stability of the population. Furthermore, the structure of the tree stand in 20 years is determined. The results can be used as a basis for monitoring the sustainability of biodiversity of a designated forest area in the northern regions with increased man-made stress, which requires data on growth curves for the population and yield of edificators, including Siberian larch.