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Öğe ANALYZING URBANIZATION, SPATIAL AND TEMPORAL LAND USE/LAND COVER CHANGE OF SAWYER DISTRICT, ISTANBUL, TURKEY(Nova Science Publishers, Inc, 2009) Keleş, Sedat; Sivrikaya, Fatih; Çakır, Günay; Ün, Cemil; Başkent, Emin Zeki; Köse, SelahattinSpatiotemporal analysis of land use/land cover is crucial in formulating an appropriate set of actions in landscape management and in developing appropriate land use policies. On the other hand, understanding the interaction between landscape pattern and land use policy is important to reveal the detrimental consequences of land use change on soil and water quality, biodiversity, and climatic systems. This study focuses on the spatial and temporal pattern analysis of land use/land cover change in the Sariyer Forest Planning Unit surrounding the district of Sariyer in a megacity of Istanbul, Turkey. The spatio-temporal pattern of the study area was evaluated with Geographical Information System and FRAGSTATS to assess the change over 31 years. As a result of population increase and urbanization, the Sariyer district expanded very fast and many changes in land use/land covers between 1971 and 2002 were realized. As an overall change, there was a net decrease of 1243 ha in total forested areas compared to a net increase of 1331 ha in settlement areas. However, both forest areas with full crown closure and regenerated or young forest areas increased due mainly to reforestation of degraded forests and agricultural areas and the conversion of coppice forests to high forests. In terms of spatial configuration, analysis of the metrics revealed that landscape structure in Sariyer forest planning unit changed substantially over the 31-year study period, resulting in fragmentation of the landscape as indicated by the higher number of large patches and the smaller mean patch sizes. In conclusion, understanding of the factors affecting the land use/land cover is increasingly important for the design and planning of urban areas and the sustainable management of natural resources.Öğe Estimation of stand type parameters and land cover using Landsat-7 ETM image: A case study from Turkey(Mdpi, 2008) Günlü, Alkan; Sivrikaya, Fatih; Başkent, Emin Zeki; Keleş, Sedat; Çakır, Günay; Kadıoğulları, Ali İhsanRemote sensing has been considered a low-cost, large-area coverage forest information resource ideally suited to broad-scale forest inventory objectives. The objective of this study is to determine stand type parameters such as crown closure, development stage and stand types, and land cover obtained from Landsat 7 ETM image and forest cover type map ( stand type map). The research also focuses on classifying and mapping the stand parameters with the spatial analysis functions of GIS. In the study, stand parameters determined by forest cover type map and remote sensing methods were compared and contrasted to evaluate the potential use of the remote sensing methods. The result showed that development stage were estimated with Landsat 7 ETM image using supervised classification with a 0.89 kappa statistic value and 92% overall accuracy assessments. Among the features, development stages were the most successfully classified stand parameters in classification process. According to the spatial accuracy assessment results, development stages also had the highest accuracy of 72.2%. As can be seen in the results, spatial accuracy is lower than classification accuracy. Stand type had the lowest accuracy of 32.8. In conclusion, it could be stated that development stages, crown closure and land cover could be determined at an acceptable level using Landsat 7 ETM image. However, Landsat 7 ETM image do not provide means to map and monitor minor vegetation communities and stand types at stand level due to low spatial resolution. High resolution satellite images could be used either alone or with field survey data.Öğe Evaluating land use/land cover changes and fragmentation in the camili forest planning unit of northeastern Turkey from 1972 to 2005(Wiley, 2007) Sivrikaya, Fatih; Çakır, Günay; Kadıoğulları, Ali İhsan; Keleş, Sedat; Başkent, Emin Zeki; Terzioğlu, SalihChanges in land use/land cover have important consequences on the management of natural resources including soil and water quality, global climatic systems and biodiversity. This study analysed the spatial and temporal pattern of land use/land cover change in the Camili forest planning unit that includes the Camili Biosphere Reserve Area within the Caucasian hotspot, in the northeast corner of Turkey. To assess the patterns during a 33-year period, the necessary data were obtained from forest stand maps and evaluated with Geographic Information Systems and FRAGSTATS. Results showed that the total forested areas increased from 19 946 center dot 5 ha (78 center dot 6% of the study area) in 1972 to 20 797 center dot 3 ha (81 center dot 9 per cent) in 2005 with a slight net increase of 851 ha. Softwood cover types (411 center dot 8 ha) completely transitioned to other cover types over 33-year period. In terms of spatial configuration, the total number of forest fragments increased from 172 to 608, and mean size of forest patch (NIPS) decreased from 147 center dot 7 ha to 41 center dot 8 ha during the period. Nearly 84 per cent of the patches in 1972 and 93 per cent of them in 2005 generally seem to concentrate into 0-100 ha patch size class, indicating more fragmented landscape over time that might create a risk for the maintenance of biodiversity of the area. There were apparent trends in the temporal structure of forest landscape, some of which may issue from mismanagement of the area, social conflict, and illegal utilization of forest resources due to ineffective forest protection measurements. The study revealed that it is important to understand both spatial and temporal changes of land use/land cover and their effects on landscape pattern to disclose the implications for land use planning and management. Copyright (C) 2007 John Wiley & Sons, Ltd.Öğe EVALUATING URBANIZATION, FRAGMENTATION AND LAND USE/LAND COVER CHANGE PATTERN IN ISTANBUL CITY, TURKEY FROM 1971 TO 2002(Wiley, 2008) Çakır, Günay; Ün, C.; Başkent, Emin Zeki; Köse, Selahattin; Sivrikaya, Fatih; Keleş, SedatSpatiotemporal analysis of landscape dynamics is crucial in formulating an appropriate set of actions in landscape management. This paper presents a large scale analysis of the spatiotemporal structure of Istanbul, a highly urbanized city in Turkey, from 1971 to 2002 using forest cover type maps analysed with geographical information systems (GIS) and a spatial statistics programme. The quantitative evidence indicated that increasing population and expanding urbanization caused drastic changes to the temporal and spatial dynamics of land use/land cover pattern in Istanbul. There was a net increase of 5387.3ha in total forested areas (1.0 per cent) due to mainly reforestation activities even though the population increased three times over a 31-year period. Increase in number of patches and decrease in mean patch size together demonstrated that the landscape developed into a more fragmented structure that would negatively affect biodiversity and the resilience of the ecosystems. In conclusion, plain increase in forest areas may not always be a favourable situation. The quality, composition and the configuration of forest landscape should also be analysed to present the dynamics of ecosystem in terms of ecological and economical sustainability over a longer time and larger area. Copyright (C) 2008 John Wiley & Sons, Ltd.Öğe Forest cover change and fragmentation using Landsat data in Macka State Forest Enterprise in Turkey(Springer, 2008) Çakır, Günay; Sivrikaya, Fatih; Keleş, SedatMonitoring forest cover change and understanding the dynamic of forest cover is increasingly important in sustainable development and management of forest ecosystems. This paper uses remote sensing (RS) techniques to monitor forest cover change in Macka State Forest Enterprise (MSFE) located in NE of Turkey through 1975 to 2000 and then analyses spatial and temporal changes in forest cover by Geographical Information Systems (GIS) and FRAGSTATS (TM). Forest cover changes were detected from a time series of satellite images of Landsat MSS in 1975, Landsat TM in 1987, and Landsat ETM+ in 2000 using RS and GIS. The results showed that total forest area, productive forest area and degraded forest area increased while broadleaf forest area and non forest area decreased. Mixed forest and degraded forest increased during the first (1975-1987) period, but decreased during the second (1987-2000) period. During the whole study period, the annual forestation rate was 152 ha year(-1), equivalent to 0.27% year(-1) using the compound-interest-rate formula. The total number of patches increased from 36,204 to 48,092 (33%), and mean size of forest patch (MPS) decreased from 2.8 ha to 2.1 ha during a 25 year period. Number of smaller patches (patches in 0-100 ha size class) increased, indicating more fragmented landscape over time that might create a risk for the maintenance of biodiversity of the area. While total population increased from 1975 to 2000 (3.7%), rural population constantly decreased. The increase of forest areas may well be explained by the fact that demographic movement of rural areas concentrated into Macka City Center. These figures also indicated that decrease in the rural population might likely lead to the release of human pressure to forest areas, probably resulting in a positive development of forest areas.Öğe A GIS-BASED DECISION SUPPORT SYSTEM FOR FOREST MANAGEMENT PLANS IN TURKEY(Gh Asachi Technical Univ Iasi, 2010) Sivrikaya, Fatih; Başkent, Emin Zeki; Şevik, Uğur; Akgül, Caner; Kadıoğulları, Ali İhsan; Değermenci, Ahmet SalihThis study is designed to develop a Geographic Information System (GIS) based contemporary forest management planning model (ETCAPKlasik) enabling to embrace the features of forest management planning guidelines. The model is implemented at a forest management unit level for even-age, uneven-age and coppice forests. The model has four modules as Data Input with inventory compilation, Harvest Scheduler with classical approach and Data Output as reporting and mapping with GIS functionalities. The model has been successfully tested on a case study site in Kizilcasu planning unit in Turkey. The results showed that ETCAPKlasik model easily compiled the sampling data from field inventory and mapped the results of plan (forest stratification, age class and site maps etc.). Harvest scheduling was conducted according to even-age and uneven-age planning methods. The outputs are generated according to the management guidelines. In conclusion, the model has contributed to the forest management process with the help of information technologies enabling the process to be faster, sound and timely using relatively less amount of time and labor. ETCAKlasik has the potential for use in preparing contemporary forest management planning process.Öğe Monitoring thirty years of land cover change: Secondary forest succession in the Artvin Forest Planning Unit of Northeastern Turkey(Routledge Journals, Taylor & Francis Ltd, 2007) Çakır, Günay; Sivrikaya, Fatih; Terzioğlu, Salih; Keleş, Sedat; Başkent, Emin ZekiAs a major topic in forest ecosysterns, determining plant successional changes is crucial to understanding the vegetation dynamics, composition and environmental disturbance of forest landscapes. This study is designed to evaluate the consequences of human and natural impacts on changes in secondary forest succession land cover from 1972 to 2002 in the Artvin Forest Planning Unit, in NE Turkey. This paper also contributes to the development of a framework for effective conservation of biodiversity through,forest management plans by using successional stages and land cover types. Secondary forest succession stages and land cover types were determined according to Clementsian theory and mapped with Geographic Information System (GIS) and Remote Sensing (RS) technologies through aerial photos and high resolution satellite images (IKONOS). The results indicated that the forest area in 1972 and 2002 was 88% and 80%, and the number of forest patches were 106 and 222, respectively. While the total road length in the Forest Planning Unit (FPU) was 67.7 km in 1972, it was 130.0 km in 2002, an increase of 62.3 km. Results shou, that urbanisation, industrial development and darn construction, together with unregulated forestry activities with clear-cut as well as insect outbreaks, affected the secondary forest succession and fragmented the forest ecosystem in the study area. Determining the secondary forest succession in detail is necessary for the sustainable management of such fragmented forest areas and for the preparation of biodiversity-friendly integrated forest management plans.Öğe Spatial and temporal changes in forest cover in Turkey's Artvin Forest, 1972-2002(Hard, 2008) Keleş, Sedat; Sivrikaya, Fatih; Çakır, Günay; Başkent, Emin Zeki; Köse, SelahattinThis study analyses the spatial and temporal pattern of land use/forest cover change in the Artvin Forest Planning Unit (AFPU) surrounding the city of Artvin, Turkey. To assess the spatiotemporal changes in forest ecosystem patterns during 1972-2002, we evaluated forest stand maps of 1972, 1985 and 2002 using Geographic Information Systems (GIS). The results showed that the total forested areas decreased from 4617 ha (88.4% of the study area) in 1972 to 4167 ha (79.8%) in 2002, with a considerable net decrease of 450 ha. 198 ha forest openings changed into settlements and agriculture during the first period (1972-1985). 158 ha degraded forest areas changed into settlements and agriculture during the second period (1985-2002). The population of Artvin increased two times over 30 years and high variability in land use/forest cover changes during the study period was reported. In terms of spatial configuration, as a result of unplanned exploitation, settlement, dam and road construction, insect Outbreaks on spruce stands, conversion and over utilization, many natural ecosystems were fragmented into small pieces in the AFPU and the total number of forest fragments rapidly increased from 108 to 202. Substantial increase in the number of patches and decrease in the average patch sizes between 1972 and 2002 indicated irregular land use and forest structure, and also suggested that human interventions had produced irregular land cover types.Öğe SPATIOTEMPORAL DYNAMICS OF LAND USE/LAND COVER AND TIMBER CARBON STORAGE: A CASE STUDY FROM BULANIKDERE, TURKEY(Nova Science Publishers, Inc, 2009) Sivrikaya, Fatih; Çakır, Günay; Keleş, Sedat; Başkent, Emin ZekiLand use/land cover change (LULCC) is regarded as the most important variable of global change affecting ecological systems with an impact on natural resources including soil and water quality, global climatic system and biodiversity. Quantification of landscape patterns through various landscape metrics can be used to describe whether the landscape pattern is changing and how, and this information may then be used to evaluate alternative ecosystem management activities and environmental conservation strategies. To analyze the spatial and temporal pattern of land use/land cover change in a forest planning unit, Bulanikdere, northwestern corner of Turkey, was selected as a case study area. The main data used in this research are forest cover type maps at 1/25 000 scale for years 1985 and 2003, their inventory data, two Landsat satellite image acquired for the years 1987 (TM), and 2000 (ETM+). Landsat TM (1987) and Landsat ETM+ (2000). The spatial and temporal analysis of the forest structure was carried out in a systematic process. First of all, the stand type maps 1985 and 2003 were digitized, rectified and the spatial database was build with ArcGIS 8.3 (TM). Second, Landsat TM and ETM+ images of 1987 and 2000 were rectified and classified to create land use/land cover type maps. Third, spatial and temporal land use/land cover changes as well as transition of cover types were analyzed with GIS. Fourth, the fragmentation of the areas was evaluated with FRAGSTATS (TM). Last, spatially explicit estimates of the carbon storage (aboveground and belowground) was determined and mapped with GIS according to inventory data for years 1985 and 2003. When both approaches were evaluated together, between 1985 and 2003 years, forest areas decreased from 7432.9 ha to 7351.5 ha according to stand type maps from management plans. On the contrary, between 1987 and 2000 years, forest areas increased from 7049,4 ha to 7456,7 ha according to land cover type maps from the classified images of Landsat TM and ETM+. During the whole study period, the average annual deforestation rate based on stand type map was 5 ha year(-1), equivalent to 0.06% year(-1) using the compound-interest-rate formula. Landscape analysis indicate that the forest landscape has been gradually fragmented and thus subjected to susceptibility of the area to further abrupt changes ill the future. It was estimated that forest ecosystems in Bulanikdere forest planning unit contain 304 264.3 tons of carbon above and below the ground according to the methodology used in this article in 1985. Though 263 895.9 tons of whole carbon storages in forest ecosystem are aboveground, the rest (40 368.4 tons) are belowground. However, it was estimated that forest ecosystems contain 510 030.1 tons of carbon with 443 032.5 tons aboveground and 66 997.6 tons of carbon belowground in 2003. As shown, carbon storages increased 205 765.8 tons during an 18 year period. There were apparent trends in the temporal structure of forest landscape, some of which may issue from unregulated management activities, social conflict and demographic movement. The study revealed that it is important to understand both spatial and temporal changes of land use/land cover and their effects on landscape pattern to release the implications for landscape planning and ecosystem management.Öğe Urbanization and forest cover change in regional directorate of Trabzon forestry from 1975 to 2000 using landsat data(Springer, 2008) Keleş, Sedat; Sivrikaya, Fatih; Çakır, Günay; Köse, SelahattinIn this study, forest cover change and urbanization in the borders of Regional Directorate of Trabzon Forestry (RDTF), which is located in NE of Turkey, was investigated during a 25 year period. Spatial and temporal changes in forest cover were also analyzed using Geographical Information System (GIS) and FRAGSTATS (TM). Forest cover changes were detected from a time series of satellite images of Landsat MSS in 1975, Landsat TM in 1987, and Landsat ETM+ in 2000 using Remote Sensing (RS) and GIS. The results showed a decrease in forest area, productive forest area and degraded forest area. Total forest area decreased in the first period (1975-1987), however increased during the second (1987-2000) period. 36 807 hectares (7% of the study area) mixed forest area converted to conifer forest. During the whole study period, the average annual deforestation rate was 977 ha year(-1), equivalent to 0.42% year(-1) using the compound-interest-rate formula. Total number of forest fragments decreased from 135,039 to 132,839 (1.6%) during a 25 year period. On the other hand, total population lived in the borders of Trabzon City increased from 1975 to 2000 even though the rural population decreased. According to the results, the decrease of forest areas may well be explained by increasing population and urbanization. The decrease of number of patches and degraded forest area can be disclosed by the fact that the decline of rural population has positively affected the development of forest areas.Öğe Using high resolution images and elevation data in classifying erosion risks of bare soil areas in the Hatila Valley Natural Protected Area, Turkey(Springer, 2010) Eroğlu, Habip; Çakır, Günay; Sivrikaya, Fatih; Akay, Abdullah E.Soil erosion is one of the most important environmental problems. In the case of small scale areas where soil properties and climate have relatively uniform characteristics, vegetation cover and topography (i.e. ground slope) are the main factors that affect the amount of soil erosion. Lack of vegetation cover on bare soil areas, including forest road side slopes, especially in mountainous regions with steep slopes, may significantly increase the erosion rate. Determining and classifying erosion risks in such areas can help preventing environmental impacts. In this study, remotely sensed data and elevation data were used to extract and classify bare soil erosion risk areas for a study area selected from Hatila Valley Natural Protected Area in northeastern Turkey. High resolution IKONOS imagery was used to apply land use classification in ER-DAS Imagine 9.0. To generate erosion risk map of the bare soil areas, classified image was superimposed on top of slope map, generated based on a Digital Elevation Model (DEM) in ArcGIS 9.2. The results indicated that 1.43, 5.85, 34.62, 53.16, and 4.94% of the bare soil areas in the study area were under very low, low, medium, high, and very high erosion risks, respectively. The overall classification accuracy of 82.5% indicated the potential of the proposed methodology.
