https://hdl.handle.net/20.500.12619/1068 2026-04-08T20:35:31Z https://hdl.handle.net/20.500.12619/3331 THE EFFECTS OF CLIMATE CHANGE ON SPATIOTEMPORAL CHANGES OF HAZELNUT (CORYLUS AVELLANA) CULTIVATION AREAS IN THE BLACK SEA REGION, TURKEY Ustaoğlu, Beyza Turkey ranks the first among the hazelnut producers in the world. The purpose of this study is to question whether or not the hazelnut plant that grows under natural climate conditions will be affected by climate change. Spatial and temporal change simulations have been done in order to define the actual and the future status of hazelnut cultivation areas. The Marmara and the Black Sea regions have been chosen as study areas of hazelnut production in Turkey. The possible evolution of the current climate conditions to affect hazelnut cultivation in the upcoming 90 years and the estimated changes to occur in hazelnut areas have been asserted in the study. In order to determine the future climate conditions, the set of temperature and rainfall data of the upcoming 90 year period (2011 - 2100) obtained from the A2 scenario of RegCM3 regional climate model has been used and by taking the averages of each 10 year period, it has been simulated with the MATLAB software. While an increase of up to 6 degrees C in temperature for the upcoming 90 years can be expected to have negative effects on hazelnut cultivation depending on the A2 scenario (the worst), no change has been observed in the rainfall scale that may negatively affect hazelnuts. In particular, it has been observed that this temperature change may cause vertical and horizontal changes in hazelnut areas. Accordingly, it has been anticipated that hazelnut cultivation on the coast line between 0 - 250 m may get affected in a negative way and the areas exceeding 1500 m that are not currently suitable for hazelnut cultivation may become arable lands due to vertical change. 2014-01-01T00:00:00Z https://hdl.handle.net/20.500.12619/3329 Remote sensing and GIS-based integrated analysis of land cover change in Duzce plain and its surroundings (north western Turkey) İkiel, Cercis; Ustaoğlu, Beyza; Atalay Dutucu, Ayşe; Koç, Derya Evrim The aim of this study is to research natural land cover change caused by the permanent effects of human activities in Duzce plain and its surroundings, and to determine the current status of the land cover. For this purpose, two Landsat TM images were used in the study for the years 1987 and 2010. These images are analysed by using data image processing techniques in ERDAS ImagineA (c) 10.0 and ArcGISA (c) 10.0 software. Land cover change nomenclature is classified according to the Coordination of Information on the Environment Level 2 Classification (1-urban fabric, 2-industrial, commercial and transport units, 3-heterogeneous agricultural areas, 4-forests, and 5-inland wetlands). Furthermore, the image analysis results are confirmed by the field research. According to the results, a decrease of 33.5 % was recorded in forest areas from 24,840.7 to 16,529.0 ha; an increase of 11.2 % was recorded in heterogeneous agricultural areas from 47,702.7 to 53,051.7 ha. Natural vegetation, which is the large part of land cover in the research area, has been changing rapidly because of rapid urbanisation and agricultural activities. As a result, it is concluded that significant changes have occurred on the natural land cover between the years 1987 and 2010 in the Duzce plain and its surroundings. 2013-01-01T00:00:00Z https://hdl.handle.net/20.500.12619/3325 Modeling stream flow and sediment yield using the SWAT model: a case study of Ankara River basin, Turkey Duru, Ümit; Mazdak Arabi; Ellen E. Wohl The Soil and Water Assessment Tool (SWAT) was tested for prediction of stream flow and sediment yield in the Ankara basin, Turkey. The overall objective of this study was to evaluate the performance and applicability of the SWAT and generate a soil erosion map. Thirteen years of daily/monthly flow and monthly sediment data were used for calibration and validation. Model performance was evaluated using statistical measures to assess the applicability of the model in simulating stream flow and sediment yield during calibration (1989-1996) and validation (1982-1984) periods. Nash Sutcliffe efficiency (NSE), relative error (RE), and R-2 (coefficient of determination) for daily flow were computed as 0.61, -0.55, and 0.78, respectively; and as 0.79, -0.58, and 0.89 for monthly flow during the calibration. Statistical comparisons of sediment yield produced values for NSE, RE, and R-2 of 0.81, -1.55, and 0.93, respectively, during the calibration. The resulting map suggests that significant portions of urbanized and highly cultivated areas in the vicinity of stream channels are particularly vulnerable to soil erosion. SWAT satisfactorily simulated hydrology and sediment yield and can be used as a tool in decision-making for water resources planning in a basin with similar characteristics. 2018-01-01T00:00:00Z https://hdl.handle.net/20.500.12619/3326 Land Use and Land Cover Changes (LULCC), a Key to Understand Soil Erosion Intensities in the Maritsa Basin Emre Ozsahin; Duru, Ümit; Ilker Eroglu Soil erosion is a major environmental and economic concern affecting all continents around the world. Soil loss facilitates land degradation, threatening both agricultural and natural environments in continental Europe. The overall objective of the present study is to reveal temporal changes of erosion risk in the Maritsa Basin, and also assess the temporal effects of land use and land cover changes (LULCC) on the gross erosion rate. The Revised Universal Soil Loss Equation (RUSLE) was utilized to monitor the distribution of the erosion risk zones and soil loss in the basin. The variables were either directly derived from the satellite imagery or computed using established equations or previous studies. The dynamic parameters were categorized into two-time frames as 1990 and 2015. The results indicate that the annual average erosion rate decreased from 0.895 to 0.828 t ha(-1) year(-1). This reduction is within the range of modeling error, potentially originated from input data uncertainties. The most extensive changes in the gross soil loss were found in both agricultural and artificial areas, which emphasize the significance of these two classes in soil erosion models. The research summarized here enhances understanding the impacts of land use and land cover (LULC) classes on erosion intensities. 2018-01-01T00:00:00Z