Evaluation of ratio-based vegetation indices for annual crops' biomass estimation : Lebna watershed, Capbon, Tunisia 2020 Mediterranean and Middle-East Geoscience and Remote Sensing Symposium (M2GARSS) Alaya, I. Zitouna-Chebbi, R. Mekki, I. /Jacob, Frédéric The sustainability of agricultural sector involves a wise water resources management and therefore an accurate spatiotemporal vegetation monitoring with relevant tools such as satellite-derived indices (VI). In this study we evaluate the performance of NDVI and NDWI indices to infer the annual crops' (mainly wheat and faba-bean) aboveground biomass(AGB)at a Mediterranean watershed. The temporal evolution of IV over the annual crops area shows the presence of low-density and low water content vegetation in early and late season. Areas with well-developed canopy and high plant water content are dominant in the mid-season. The observed AGB of wheat and faba-bean shows a good correlation with NDVI and NDWI values (R-2>0.71). The used vegetation indices represent a practical tool to determine the spatiotemporal variation of annual crops' AGB in Lebna watershed, however, a large dataset for validation is needed. IEEE 2020 text https://www.documentation.ird.fr/hor/fdi:010083682 fdi:010083682 Alaya I., Zitouna-Chebbi R., Mekki I., Jacob Frédéric. Evaluation of ratio-based vegetation indices for annual crops' biomass estimation : Lebna watershed, Capbon, Tunisia. In : . 2020 Mediterranean and Middle-East Geoscience and Remote Sensing Symposium (M2GARSS) IEEE, 2020, 326-329 M2GARSS : Mediterranean and Middle-East Geoscience and Remote Sensing Symposium, Tunis (Tunisie), 2020/11/9-11 EN TUNISIE