LAUSR

According to the IPCC sixth assessment report of the Intergovernmental Panel on Climate Change, global climate change is now unequivocal. Tunisia, like many other countries, has been affected by climate changes, including rising temperature, intense heat waves, and altered precipitation regimes. Tunisia's mean annual temperatures rise by about +1.4 °C in the twentieth century, with the most rapid warming taking place since the1970s. Drought represents a primary contributing factor to tree decline and dieback. Long-term drought can result in reduced growth and health of trees, thereby, increasing their susceptibility to insect pests and pathogens. Reported increases in tree mortality point toward accelerating global forest vulnerability under hotter temperatures and longer, more intense droughts. In order to assess the effect of these climate changes on the current state of forest ecosystems in Tunisia and their evolution, an investigative study seems necessary. Here, we review the current state of knowledge on the effects of climate change on sclerophyllous and semi-deciduous forest ecosystems in Tunisia. Natural disturbance during the last years as well as the adaptability and resilience of some forest species to climate change were surveyed. Standardized Precipitation Evapotranspiration Index (SPEI) is a multi-scalar drought index based on climatic data has been used to analyze drought variability. SPEI time scale analysis showed a negative trend over the 1955-2021 period in Tunisian forest regions. In 2021, Tunisia lost 280 km2 of tree cover ravaged by fires, which equivalent to a 26 % of the total loss area between 2008 and 2021. Changing climatic conditions have also affected phenological parameters with an advance of the start of the green season (SOS) by 9.4 days, a delay of the end of the green season (EOS) by 5 days, with the consequent of the extension duration of the green season (LOS) by an average of 14.2 days. All these alarming findings invite us to seek adaptation strategies for forest ecosystems. Adapting forests to climate change is therefore a challenge for scientists as well as policy makers and managers.