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Identifying fire-affected areas is of key importance to support post-fire management strategies and account for the environmental impact of fires. The availability of high spatial and temporal resolution optical satellite data enables the development of procedures for detailed and prompt post-fire mapping. This study proposes a novel approach for integrating multiple spectral indices to generate more accurate burned area maps by exploiting Sentinel-2 images. This approach aims to develop a procedure to combine multiple spectral indices using an adaptive thresholding method and proposes an agreement index to map the burned areas by optimizing omission and commission errors. The approach has been tested for the burned area classification of four study areas in Italy. The proposed agreement index combines multiple spectral indices to select the actual burned pixels, to balance the omission and commission errors, and to optimize the overall accuracy. The results showed the spectral indices singularly performed differently in the four study areas and that high levels of commission errors were achieved, especially for wildfires which occurred during the fall season (up to 0.93) Furthermore, the agreement index showed a good level of accuracy (minimum 0.65, maximum 0.96) for all the study areas, improving the performance compared to assessing the indices individually. This suggests the possibility of testing the methodology on a large set of wildfire cases in different environmental conditions to support the decision-making process. Exploiting the high resolution of optical satellite data, this work contributes to improving the production of detailed burned area maps, which could be integrated into operational services based on the use of Earth Observation products for burned area mapping to support the decision-making process.

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To determine the combined effects of stream acidification and competition on the feeding preferences of benthic detritivores we compared, before and after sublethal acid exposure, lab-cultured populations of Asellus aquaticus reared either singly or with the closely related species Proasellus coxalis sensu lato in artificial channels. Both abiotic and biotic stressors reduced A. aquaticus density and affected its food intake. Whereas the presence of P. coxalis sensu lato increased the mass-specific ingestion rate and niche breadth of A. aquaticus according to optimal foraging theory, ingestion rate was reduced following acid exposure. Despite the increased variability in the consumption rate, variability of diet composition among individuals of A. aquaticus declined after acidification above all in the presence of the other species. Resource preferences changed, as a possible result of physiological accommodation to stress and/or selection of individuals that preferentially consumed the most processed plant detritus. The symmetry of niche overlap between the two species increased, strengthening the risk of competitive exclusion of A. aquaticus. The presence of the detritivores increased the buffering capacity of the artificial channels, reducing the rate at which the temporary hardness declined.