The Impact of Mediterranean Droughts and Large Fires on the Carbon Balance of Vegetation

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<p>Over the last decades, the vegetation dynamics have been severely disturbed due to the increasing intensity and occurrence of extreme events. The activity of terrestrial ecosystems is particularly susceptible to the climate variability, and their recently regional changes, mainly linked to the occurrence of extreme climatic events, are leading to rapid changes on natural vegetation cycle, plants productivity and terrestrial carbon cycle.</p><p>Droughts have been broadly recognized, among a wide range of extreme events, as playing a central role on the carbon cycle. Dry conditions contribute to the occurrence of high hydrological stress on vegetation, generating disturbances on the regular photosynthesis and vegetation mechanisms. Furthermore, they may increase the risk of fires, enhancing the losses on carbon stocks and plants productivity and inhibiting the ecosystems to regenerate and recover for a long time.</p><p>A wide range of works have recently shown that Europe, and in particular, the Mediterranean region, has been affected by severe droughts and large fires in the last decades. Therefore, we propose to assess the impact of a set of the severest droughts and large fires, between 2001 and 2019, over three different regions of Mediterranean basin, in order to assess their influence on vegetation, by evaluating the persistency of soil dry conditions and the observation of the number of months that vegetation’s activity is disturbed. This analysis allowed the quantification of the carbon losses occurred due to the referred extreme events, and also, the observation of the time response and recovery process of vegetation during the following months. In this study, we used remote sense products to monitor the vegetation production and activity (MODIS GPP and PSNet), to assess the soil moisture (ESA CCI SM) and to detect burned areas (FIRE CCI51).</p><p> This work was supported by FCT through projects IMPECAF (PTDC/CTA-CLI/28902/2017), FIRECAST (PCIF/GRF/0204/2017) and by IDL (UIDB/50019/2020).</p>