Condition and Stability of Plantations in the Zonal Ecotone of the Forest and Steppe of the Southern Urals

Abstract

Abstract In the conditions of the zonal ecotone of the forest and steppe of the Southern Cis-Urals, the current state of forest ecosystems is characterized, the radial growth of Scots pine is considered as an indicator of the sustainability of plantations. Forest phytocenoses of the Southern Cis-Urals have class 2 and 3 of biological resistance, unfavorable in sanitary terms, which leads to the appearance of permanent foci of mass reproduction of insect pests of leaves and needles. These pests are actually indicators of the sustainability of the forest ecosystem. The plantations are especially strongly weakened in the zone of medium, strong and maximum anthropogenic impact on the environment. Differences in the radial growth of Scots pine are observed in the zonal ecotone of the forest and steppe. The dynamics of the radial growth of Scots pine in the Orenburg forestry indicates a decrease in the indicator over the years, which is interconnected with the dry climate of the steppe zone and partly the technogenic influence of industrial enterprises in Orenburg. The dynamics of the radial growth of Scots pine crops in the national park "Buzuluksky bor", on the contrary, increases over the years, which, in our opinion, is associated with more humid growing conditions in recent years. Comparing the average radial growth of Scots pine in the zonal ecotone of the forest and steppe, one can note higher rates in the forest zone of the national park "Buzuluksky bor" and lower rates in the steppe zone. The main method of collecting information on the state of forest cenoses was a field survey on temporary test areas, which were laid according to standard methods.