One of the most ecological problems worldwide is a climate change that could impact forests, so study of this issue is very important to provide proper response and making informed decisions on forest management.
The aim of the study is modeling of climate change impact on the viability of coenopopulations of main forest forming species (Pinus sylvestris L. and Quercus robur L.) and evaluation of their vulnerability to climate change in plain part of Ukraine according to IPCC scenario A1B at XXI century comparing to climate norm (1961–1990).
Materials and Methods
By means of Q-GIS, climate maps in dynamics were created. Regional climate models of EU-FP6 ENSEMBLES and E-OBS of ECA&D projects and regional climate models were used. On the base of scales of ecological (climatic) amplitudes (by Didukh Ya.P.), bioecological characteristics (amplitude of tolerance) for pine and oak were assessed for climate continentality and humidity (by Ivanov), and cryoclimate (average temperature of the coldest month). Scoring scales for environment satisfactory were created. We have modeled spatial distribution of areas with different satisfactory conditions of climate (optimal, suboptimal, etc.) for oak and pine at climate norm 1961–1990, in present (1990–2010), and forecasted by A1B scenario (IPCC) – on 2011–2030, 2031–2050 and 2081–2100.
Oak and pine species have the narrowest amplitudes of tolerance on humidity, so it is the limiting factor. Pine has relatively wider amplitude, but oak is adapted to relatively drier ecological conditions.
Comparing to climate norm at present zones of optimum and suboptimum for oak narrowed and shifted to the west; the border of satisfying conditions moved to the north-west. Zone of satisfying conditions for pine shifted to the west and narrowed, and zone of unfavorable conditions significantly increased.
According to the A1B scenario, further shifting of zones to north-west direction and increasing of the area of unsatisfying conditions for oak and pine is expected. By the end of the XXI century favorable conditions for oak will remain only at the west at the Carpathians and foothills and satisfying conditions, at Lviv region, while on the remaining territory of mixed-broadleaved forests zone, conditions for oak will be unsatisfying and extremal. For pine, the forecast is more negative: by the end of the century conditions suitable for pine growth (mainly less satisfying and extremal) will remain only at the west and fragmentary at the north.
For assessment of climate change impact the method of forecasting of the main forest forming species condition by continentality, humidity, and cryoclimate by categories of satisfactory of the environment was developed.
For oak and pine, the limiting factor is the humidity. According to the forecast, a significant reduction in the zone of optimum in 2080–2100 is expected, and the appearance of areas with unfavorable conditions (more for pine than for oak), which increases the probability of changes in zonal vegetation types of flat interfluves. In places with unfavorable climatic conditions, a significant decrease in the productivity of oak and pine is predicted, gradual loss of their reproductive capacity, violation of seasonal development cycles, reduction of resistance to pests and diseases, and the increased risk of forest fires.