Mudanças climáticas no eucalipto: modelos de desenvolvimento e zoneamento de aptidão climática

Abstract

The climate projections indicate an increase in air temperature and changes in rainfall patterns throughout the Brazilian territory, which may impact the cultivation of forest species. Thus, it becomes important to conduct studies that analyze the potential impacts of climate projections, especially for those economically important, such as eucalyptus. Given these aspects, the aims of this master's thesis were: a) to calibrate and evaluate the development simulation models Phyllochron (PHYL) and Wang and Engel (WE) for the present climate, as well as to identify the possible impacts of projected increases in air temperature on the duration of the seedling phase (SDP) of two species of eucalyptus, considering two scenarios of radioactive forncing (RCP 4.5 e RCP 8.5) and; b) to evaluate the impacts of climate projections in agroclimatic zoning for the main species of eucalyptus cultivated in Brazil, considering the water and thermal limitations of the species for two scenarios of radiative forcing. The two models (PHYL and WE) were able to predict the dynamics of development in two species, with better performance of the WE model. The projected increase in air temperature throughout the 21st century may modify the development rates and SDP of the two species of eucalyptus cultivated in Itajubá, as well as in subtropical climate regions, reducing the development rate, and increasing the permanence of seedlings in forest nurseries. There will be no considerable changes in the adequate areas for eucalyptus cultivation in Brazilian territory for the near future (2021-2050). However, at the end of the 21st century (2071-2100) there may be a reduction from 3% (RCP 4.5) to 7% (RCP 8.5) of totally or adequate areas of eucalyptus cultivation comparead to present climate (1980 – 2005), and the appearance of restricted areas, up to 47%, due to the increase of water deficit in eucalyptus cultivation in the far future.