Analysis of land cover change of some sub-bains connected to the main river of Çınarcık Dam with remote sensing techniques

Rapid population growth and the advent of the industrial revolution in the 18th and 19th centuries bring about rapid changes in land use/cover. Land use and land cover change over time for both natural and anthropogenic reasons. Agricultural areas, forest areas and pastures are deteriorating, leading to the uncontrolled spread of man-made lands such as urbanization and industrialization. Scientific studies have led to new studies on land use/cover concepts on remote sensing. Basin management is the process of shaping and evaluating the use of the natural resources of a basin in order to provide the desired products and services in line with the needs of the soil and water resources of a basin. However, in order to achieve the objectives of watershed management, it is necessary to identify the basins one by one and evaluate each one individually. In other words, watershed management is the economic, ecological and socio-cultural development of the society and the sustainable planning, management and development of the natural resources collected from the source. Soil losses are experienced in Turkey as a result of exposure to erosion caused by the misuse of the land. In our country, where the population is increasing day by day, the utilization of the lands in accordance with their potential will provide national development. The spatial determination of the temporal changes of the land cover/use on the earth and the determination of the spatial changes are necessary for planning. It can be achieved by using Remote Sensing (UA) and Geographical Information Systems (GIS) systems in order to obtain historical information. Remote Sensing (UA) can detect land cover/use change by using past and present satellite images for the same location. Located in the Orhaneli district of Bursa, which is located in the Marmara Region in Turkey, there is the Sea of Marmara in the north, Kütahya in the south, Bilecik in the east and Balıkesir in the west. The study area is the upper basin of the Çınarcık Dam, which started service in 2008 on the Orhaneli Stream in Bursa, Turkey. The study area was determined as 9093.5 ha. Çınarcık Dam is one of the water resources with the highest potential among the water resources in Bursa. 145 hm3/year industrial and drinking water is obtained from Çınarcık Dam. This change in the population of Orhaneli district also caused a change in agricultural areas. One of the biggest effects of migration from the village to the city in our country can be shown as the decrease in occupations such as farmer and farmer dealing with agricultural fields in the past. This situation also causes a decrease in agricultural areas. While 2452.7 hectares of agricultural land were determined in the 1997 classified land cover/use, this area decreased to 1924.2 hectares in the 2020 classified land cover/use. Agricultural areas are shown in yellow on classified land cover/use maps. According to the classified land cover/use in 1997, there is an open area of 617 ha. These lands generally consist of stony rocky barren lands, clearings in forests and a few mining sites. This situation is changing as of 2020. According to the classified land cover/use in 2020, the open areas in the study area increased up to 1052.1 hectares. In this case, there is no doubt that there is an effect of 15-20 mines operating in the study area. In the east of the classified land cover/use map of 2020, it can be seen that there are many brown mines in a circular shape formed in brown. In addition, the amount of increase in these open areas reveals that there is an increase in stony and rocky areas. This shows that erosion is effective in the study area. Forest areas, which were 5304.8 hectares in 1997 classified land cover/use, increased to 5694.7 hectares in 2020 classified land cover/use. This situation also supports the fact that Turkey's forest assets are increasing every year. The declining population in the study area also reduces the pressure on forest assets, as well as the impact of forestry activities such as conversion of coppice forests into groves and afforestation.