Seasonal Dynamics of Vegetation in the Wetlands of the Lower Dniester NNP Based on Remote Data from the Landsat-8 Satellite

Abstract

Over the season of 2020, the vegetation dynamics of the wetlands in the Lower Dniester National Nature Park were examined using the indices NDVI (Normalized Difference Vegetation Index) and VCI (Vegetation Condition Index) on the basis of Landsat-8 satellite remote sensing data. The results demonstrated that distribution of values throughout the vegetation season did not correspond to normal distribution, indicating variety of their habitat conditions. The vegetation development in spring was negatively affected by the pyrogenic factor, which formed some areas without vegetation and with poorly developed vegetation. Sharp increase in NDVI values in early summer occurred due to development of wetland ecosystems' edifier Phragmites australis, whose stems emerged from the pickle stage and developed a leaf lamina. In this period, the well-developed vegetation prevailed, its total area exceeded 97%. In autumn, the areas of the developed vegetation gradually decrease, whereas areas of the poorly developed increased. The results of the research showed effectiveness of remote sensing of wetland areas using NDVI and VCI to assess vegetation state; it also can be used for the purposes of the conservation, restoration and sustainable use of wetland ecosystems of the north-west Black Sea coastal area under increasing anthropogenic pressure and global climate change.