Emiliya Velizarova

Assessment and mapping of the current state of the landscapes/ecosystems in Haskovo region (southeastern Bulgaria) in relation to ecosystem services using remote sensing and GIS

Assessment and mapping of the ecosystems state in the context of ecosystem services that they supply are important tasks to improve human well-being, especially in regions with considerable land degradation. Haskovo region is situated in the Southeastern part of Bulgaria and is considered as an extremely sensitive to land degradation in terms of climate change and human activities in result of unappropriated land management practices. In order to improve the conservation activities and ecosystem services of the region, rapid and available technics are needed in addition to the used analytical methods. The study presents the potential of remote sensing methods (satellite data from different sensors Sentinel and Landsat) and GIS for assessment of the current state of the landscapes to supply ecosystem services and allows a comprehensive evaluation of the main indicators for assessment of ecosystem services to be performed. The proposed methodology includes application of vegetation indices (NDVI, NDWI and MSAVI2) and SAR data. The results show that the referred technics can be used for a rapid and accurate assessment of the main indicators showing the state of the terrestrial ecosystems such as: soil degradation, land use and impact of human activities, responsible for the ecosystem services supply.

On the Game Method for the forest fire spread modelling with considering the wind effect

Short description of the Game Method for Modelling (GMM) is given. On GMM base, a model of forest fire is constructed. The model is an illustration of the possible applications of the GMM. It represents the case of wind presence. Intuitionistic fuzzy interpretation of the degree of burnt forest mass.

Application of remote sensing data for forest fires severity assessment

Forest fires continue to burn large territories, both within and outside Europe. It is suitably to assess fire-induced changes in the vegetation, which in turn affects infiltration, runoff, and erosion potential. Therefore it is important to identify potential areas of concern and prioritize field reconnaissance. The development of a burn severity map will facilitate quantifying of the post-fire assessment phase. In this study the potential of Normalized Burn Index (NBR), Normalized Difference Vegetation Index (NDVI) and normalized difference greenness indices (NDGI) derived from remote sensing methods (satellite data from different sensors Sentinel and Landsat) and Geographical Information System (GIS) have been analyzed for forest fire severity assessment. For more accurate assessment of the fire severity, a hybrid model was developed, using satellite data from different sensors - Sentinel and Landsat. For this purpose, the area, affected by fires occurred in august 2017 on the northwest slopes of the Ajtovska Mountain (East part of the Stara planina mountain) in the Eastern part of Bulgaria was studied. The forest fire events were spread on the area of (508.5 ha) and the affected vegetation was composed by deciduous forests (309.4ha), coniferous (62.4ha), mixed forests (61.4 ha) and grass and shrubs (75.3ha). Through the model developed, results applicable to the actual forest ecosystem conditions for different time intervals have been obtained. These results provide quantitative information about fire severity for distinct forest types, thus allowing for designing relevant fire severity maps.