Vegetation mapping of the southern part of the Sakhalin Island by data of decoding images of the Landsat satellite system

Abstract

The purpose of the research is to determine the factors that have a significant impact on the distribution structure of plant communities over the territory and to draw up a vegetation map. The article pre-sents the analytical results of the vegetation cover diversity and geobotanical mapping of the territory based on the data of decoded satellite images. Materials and methods. The main sources of information for the study are materials of field geobotanical studies and satellite images of medium spatial resolution obtained from the Landsat-8 satellite, which provided an assessment of the current state of forest communities. Modern compilation and design of maps is characterized by the widespread use of GIS technologies and computer analysis methods. To decrypt and process the images, the ENVI, ArcGIS, and QGIS software complexes were used. The final processing and design of the cartographic material was carried out using the Adobe Illustrator program. Results. The southern part of the Sakhalin Island territory was chosen as the object of research, on which a large number of east-asian species, including tree and shrub forms, grow. In the Yuzhno-Sakhalinsk floristic region, the flora of the North-Japanese type prevails, and the presence of northern species characteristic of the dark coniferous taiga zone is noticeably reduced in its composition. Krillionsky district is distinguished by the presence of species common with the Southern Kuril Islands and the Hokkaido Island. The re-sults of studying the spatial distribution of forest landscapes served as a basis for identifying the most resistant to climate change plant communities, as well as those capable of rapid recovery after forest fires. Climatic conditions have been analyzed, which made it possible to identify trends in the long-term dynamics of plant communities in the territory. The analysis of long-term dynamics made it possible to identify the current state of forest communities, predict certain negative natural phenomena (fires, waterlogging, etc.). Conclusions. The dynamics of the state of forest plant communities is clearly determined by the data of satellite surveys. The map, compiled on the basis of the results of space images interpretation, reflects the spatial distribution and state of the vegetation cover of the territory, enables to make an inventory of plant associations, to establish the boundaries of geobotanical regions in their current state.