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One of the largest fires in the Croatian history, so called ‘mother of all fires’, broke out on Monday, 17. July 2017 in the area between Split and Omiš (Croatia). The fighting with the firestorm lasted until 18. July when the situation was put under control, and on 19. July, the recovery of the affected area started. The classification showed that the burned area was 40670 square kilometers large. Vegetation indices obtained from aerial or remote sensing imagery are very simple and effective methods for quantitative and qualitative evaluations of vegetation cover and growth dynamics, among other applications. These indices have been widely implemented within remote sensing applications in agronomy and forestry (for example). Spectral characteristic of vegetation were analyzed immediately prior to the fire and one year after the fire for the purpose of observing the recovery of the burned vegetation. This paper reviews values and analysis of three selected vegetation indices: Normalized Difference Vegetation Index (NDVI), Green-Red Vegetation Index (GRVI) and Ratio Vegetation Index (RVI) for the mentioned periods and locations. The channels of the satellite system Sentinel-2 were used for the calculation of the mentioned indices. The classification of the area was made immediately after the fire for the purpose of achieving a better insight into the scale of the fire itself and to define the areas for the purpose of comparison as accurately as possible. Further studies, on the other location, should focus on obtaining more precise variables (in situ measuring and involving experts from forestry or agronomy) which help to explain post-fire vegetation recovery better. [ABSTRACT FROM AUTHOR]

Copernicus is a European Union programme designed to provide a service in delivering free, openly accessible data about the Earth's surface through satellite and in-situ observations. On the other hand, Landsat represents the world's longest standing continuously acquired collection of space-based, moderate-resolution, land remote sensing data for those working in agriculture, geology, forestry, regional planning, education, mapping, and global change research. Although the images of these satellite systems are characterised by coarse resolution, they can be a good source of information and data to provide better observation of certain objects or phenomena of interest to experts and help them in decision-making. This paper presents an analysis of the vegetation indices of urban vegetation in the city of Zagreb, Croatia, during 2017, calculated using Sentinel 2 and Landsat 8 bands. The information and data obtained as the results of interpreting and processing Sentinel 2 and Landsat 8 satellite systems images can be used by experts in forestry and urban planning as a support in making decisions on urban vegetation management. The results obtained were analysed and interpreted. The interpretation of the results was made visually and statistically, and then presented by means of statistical parameters (correlation, regression). Some channels of the Sentinel 2 satellite system have better surface resolution than all the multispectral channels of the Landsat 8 satellite system. However, the Landsat 8 satellite system channels have better surface resolution than some Sentinel 2 satellite system channels. In both cases, a surface resolution is 10 m and higher. So it is not possible to precisely identify certain objects and phenomena of interest in the field, but only to detect them with a certain level of confidence. Therefore, processing that included the channels of both systems was performed. [ABSTRACT FROM AUTHOR]