Climate changes and their impacts on Romanian mountain forests

摘要

Forest systems are all sensitive to climatic factors and extreme events and are likely to have different vulnerability thresholds according to the species, the amplitude, and the rate of climatic stressors. As a result of global climate change, there is growing evidence that some of the most severe weather events could become more frequent in Romania over the next 50 to 100 years. Effects of climate extremes on forests can have both short-term and long-term implications for standing biomass, tree health and species composition. Multispectral, multiresolution and multitemporal satellite imagery is used to classify and map various forest and spatio-temporal land-cover changes, In mountain forests, the more frequent occurrence of climatic changes may accelerate the replacement of sensitive tree species and reduce carbon stocks, and the projected slight increase in the frequency of extreme storms by the end of the century could increase the risk of windthrow. Mountain forest landscape pattern and the biogeophysical variables (NDVI, EVI) controlling observed patterns can be addressed using time series remote sensing satellite imagery. The specific aim of this paper was to: 1) quantify the changes and rates of change between 1990 and 2011 in vegetative composition across a forest landscape in Romanian Carpathians on Prahova Valley using Landsat TM/ETM, IKONOS, MODIS images; 2) examine the changes in landscape structure in relation with climatic changes and extreme events; 3) assess the climate risks and their potential impact on Romanian mountain forests; 4) analysis of mountain forest spatio-temporal land cover composition, pattern and structure.