Regulatory Roles of Boreal and Nemoral Forests in the Volga River Basin in Carbon Cycle and Anthropogenic Warming Mitigation: A Predictive Empirical-Statistical Modeling Study

The well-known conceptual provisions on the ecological resources of forest cover as their ability to additionally absorb greenhouse gases through the mechanisms of carbon cycle regulation under global climate change are empirically substantiated. A predictive landscape-ecological analysis of forest cover in the Volga River basin is presented, which highlights the task of greenhouse gas sequestration included in the list of tasks of the Paris Agreement (2015) on climate change. Data from large-scale landscape surveys previously conducted by the author in the Middle and Upper Volga regions were used. Calculations of the carbon balance of forest formations in the Volga River basin were performed for global moderate and extreme warming scenarios. Multiple regression methods were used to reveal the spatial variability of forest carbon balance in relation to changes in forest ecosystems' adaptive potential and the climate predicted for 2100 by the global HadCM3 model, which was consistent with the current unprecedented rate of global warming. The absorption potential of indigenous and derivative boreal and nemoral forests was established; their ability to mitigate the effects of climate change, including the reduction of anthropogenic warming, was assessed. Contrasting changes in the ecological resources of boreal and nemoral forests amid global warming were identified. A quantitative assessment of the loss of ecological resources of forests in the Volga River basin since the beginning of intensive forest and land utilization was conducted. Using the Volga River basin as an example, a regional experiment was conducted to numerically solve the dual problem set by the Paris (2015) Agreement on Climate Change: namely, to calculate the sequestration of CO2 from the atmosphere by forest communities under current global warming, taking into account their adaptation to climate change.