Changes in the Structure of Forest Communities in Penza Region under the Influence of Natural Factors

Abstract

This article presents the factors influencing the formation and viability of woody vegetation in the forests of Penza region, located at the border of broad-leaved forests zone (north-eastern part) and forest-steppe (west-ern half and south-eastern part). According to the results of the National Ecological Rating of Regions, Penza region ranked 28th out of 85 Russian regions where environmental pollution is monitored. The total land area of forests is 999.3 thousand hectares, or 23.0% of the total land area of Penza region. Operational forests occupy 413.1 thousand hectares or 45.1% of the total area of land area of forest fund. Protective forests occupy 502,100 ha or 54,9% of total area of lands of forest reserve. Coniferous (pine, spruce), soft-leaved (birch, aspen, linden, alder, willow, poplar) and hardleaved (oak, ash, maple, elm) forest plantations grow on the territory of Penza region. The predominant and main tree species are Pínus sylvestris, Quercus robur, Betula pendula, Populus tremula, Tília cordata and Fraxinus excelsior. Every year, the region’s forests are affected by abiotic, biotic and anthropogenic factors. As a result of these processes there is a weakening of trees and their increased retreat in the plantation. Among the range of negative impacts on the condition of the region forests the first place is occu-pied by forest diseases (68,9% of the total area of all the negative factors), the second place - by weather condi-tions and soil and climatic factors (22,2%), the third - by forest fires (7,7%). In general, the condition of forests in Penza region is satisfactory. The most important task of forestry is to increase the productivity and quality of forests.