Investigation of land cover status and temporal land cover change in Turkey and its phytogeographic regions with the help of remote sensing and geographic information systems

The surface of the Earth has been constantly changing since its existence. Some of these changes can be seen as the natural processes of the ecosystem. However, the anthropogenic effects on the land, which has greatly increased by the industrial revolution, disrupt the dynamics of the ecosystem. These changes on land cover negatively affect soil quality, water quality and presence, climate and living creatures on earth. In order to determine the negative effects, their scope and adverse conditions that may occur in the coming years, it is very important to examine the current situation of the land cover and its change in time. Nowadays, this study subject, which has greatly increased its popularity, can be made easily by providing savings from time, labor and costs with the help of geographical information systems and remote sensing techniques. Within the scope of this thesis, land cover maps of three different temporal periods were planned to be constructed with Landsat satellite images having a medium spatial resolution (30 meters) and covering the borders of our country with the use of geographical information systems and remote sensing techniques. Due to the lack of land cover and change studies in native and foreign literature with the help of a medium or high resolution satellite or aerial images in different temporal periods for the borders of Turkey, it was determined that it is necessary to study this subject. Generating and testing a different image processing method, investigating current and historical land cover conditions and land cover changes of Turkey, and investigating current and historical land cover conditions and land cover changes of phytogeographical regions of Turkey which have different climatic and floristic characteristics were planned as main purposes of this study. Many different image processing methods are used in the creation of land cover maps. Before starting large-scale studies, testing the pilot area or areas to be selected with different image processing techniques increases the accuracy of the study. The process of converting three land cover maps with the most accurate from the land cover mapsobtained by using these image processing techniques to a single land cover map is named 'The Best Three' (TBT) image processing method in this study. It was observed that the average accuracy and the kappa coefficients of the land cover maps increased with this method. Thus, covering the entire border with Turkey, belonging to three different time periods, 150 Landsat images was decided to be processed with this method. The current land cover map, which is composed of TBT method, covering the borders of our country, has been subjected to a accuracy assessment and very high accuracy rates such as 91% average accuracy and 0.876 kappa coefficient have been obtained in this study. The land cover maps of the previous years have not been subjected to accuracy analyzes because of the difficulty of the selection of sample areas. In addition to the country and phytogeographic results obtained by TBT method, CORINE land cover data sets were included in the study and compared with the results obtained. Considering the results obtained for whole country, there has been found a great increase in densely forested areas and has been found to an increase the green fields in 30 years. However, when the CORINE 3rd level land cover classes were examined carefully, it was seen that mixed forest compositions decreased considerably in our country. Except for forests, the increase in wetlands and agricultural fields and in decrease in sparsely vegetated areas are another remarkable results. When the changes in the floristic regions are examined, it has been determined that the EuroSiberian and Mediterranean phytogeographic regions have retained and increased their characteristic structure, while in Irano-Turanian phytogeographic region an unexpected increase in forested area was observed. This thesis study can be called as the most detailed land cover study for the borders of our country. The data obtained in this study are very important in terms of the relevant ministries, general directorates, city planners and academicians of our country and they are great data sources for future activities. With the help of rapidly advancing technology, these and other studies can be developed and it is foreseen that there will be the most applied studies to deal with global problems such as global climate change.