1,720,963 research outputs found
Analyzing land cover changes of Osmancik (Corum, Turkey) basin with landsat TM images
No full textThis research involves land cover changes of Osmancik Basin. The basin, is located in northern, part of Turkey, between 40 degrees 48' - 41 degrees 40' north latitudes and 34 degrees 41' - 35 degrees 04' east longitudes. The aim of this study is to research the permanent effects of human activities on natural land cover change. For this purpose, satellite images which enclose 1987 - 2010 periods are used as data. Erdas Imagine 10.0 software was used to analyse these images by using data images (Landsat TM) processing techniques. Land cover change nomenclature, is made due to Corine (Coordination of Information on the Environment) Class 2 (Urban fabric, Forest, Shrub and/or herbaceous vegetation association, Heterogeneous areas, Inlands wetlands) and Class 3 (Rice fields). All images were independently classified using the supervised classification method of maximum likelihood algorithm. As a result, a period of over 20 years deforestation was calculated 62% from 66663, 1 to 25266, 2 hectares between 1987 and 2010. In the same period, urban fabric changing was observed 190 % from 1949, 8 to 5671, 8 hectares. On the contrary, Inland wetlands have increased from 429, 4 to 1641, 6 hectares because of the built up new big dam named Obruk
Vegetation geography of western part of Elmacik mountain, Turkey
No full textThe study examines the western part of Elmacik mountain from the perspective of vegetation geography. Research area is within the phytogeographical region of Euro-Siberian that is among the flora and phytogeographical region of Turkey. According to Turkey's grid square system, the research area is located in the A3 square. The main elements of forest formation consist of Fagus orientalis, Abies nordmanniana subspp. bornmuelleriana, Pinus nigra subsp. pallasiana, Pinus sylvestris, Quercus spp., Platanus orientalis and Tilia argentea. Humid forests are dominant and the main elements of shrub formation consist of Buxus sempervirens, Rubus sanctus and especially Rhododendron ponticum subsp. ponticum. The main herbaceous formation area consists of Digitalis ferruginea subsp. ferruginea, Fragaria vesca, Euphorbia falcata, Crocus colchicum kotschyi and Verbascum sp. Distribution of natural vegetation varies due to climate, soils and morphologic character and of the research area. This situation was examined and defined by applying field surveys and geographical information systems
Remote sensing and GIS-based integrated analysis of land cover change in Duzce plain and its surroundings (north western Turkey)
No full textThe 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
Analysing land cover change with RS and GIS methods in the Elmacik Mountain and its surroundings, Turkey
No full textIn this research, land cover change in the Elmacik Mountain and its surroundings is investigated. The study area, the Elmacik Mountain, is located in the north-western part of Turkey between the coordinates of 40 degrees 32'-40 degrees 45' N and 30 degrees 35' - 31 degrees 24' E. This area covered with humid forests is located in the Euxine province of Euro - Siberian phytogeographical region. Fagus orientalis communities constitute climax plant community of these forests. Negative effects of population growth, urbanization and industrialization on natural environment can be observed in this research area surrounded by the cities of Sakarya and Duzce. Moreover, we observed that the forest was destroyed and converted into agricultural lands by the rural population of the area. The aim of this study is to analyze natural land cover changes as a result of the permanent effects of human activities in the area, and detect the current status of this area. For this purpose, Landsat TM satellite images which have different spatial resolution are used as data between the periods of 1987 - 2010. These images are analyzed by utilizing data image processing techniques in ERDAS Imagine (c) 10.0 and ArcGIS (c) 10.0 software. Land cover change nomenclature is classified according to the CORINE (Coordinationt of Information on the Environment). Furthermore, image analysis results are confirmed by the field research. As a result, it is concluded that significant changes have occurred on the natural land cover between the years 1987-2010 in the Elmacik Mountain and its surrounding area
The Heavy-Metal Accumulation in Some Aquatic Plants and their Spatial Distributions in the Lower Sakarya River Basin (Turkey)
No full textTo evaluate aquatic macrophyte species, an indicator organism of heavy-metal pollution in bio-monitoring studies of the aquatic ecosystem is studied. The aim of this study is determining some heavy-metal (Pb, Cr, Cu, Mn, Ni, Zn, and Cd) accumulation of aquatic plants in the lower Sakarya river basin which is located in northwestern Turkey. This study is performed by collecting aquatic plants from the research area (Poyrazlar Lake, Taskisigi Lake, Sapanca Lake, and Acarlar Longoz) between December 2012 and 2013. After the solution process of the plants is performed, Pb, Cr, Cu, Mn, Ni, Zn, and Cd amounts are determined by ICP-OES device. The determination of seven elements in the samples was performed by ICP-OES. The experimental results comply with the reported values in the literature. According to the analysis, heavy-metal concentration of the plants in the Sakarya river basin is between the range of Cu 2.0 +/- 0.1-30.0 +/- 0.8 mu g/g, Mn 2.3 +/- 0.2-12.5 +/- 0.8 mu g/ g, Ni 0-2.5 +/- 0.3 mu g/g, and Zn 12 +/- 0.2-800 +/- 0.8 mu g/g. Pb, Cr, and Cd amounts could be detected. Regional accumulations are interpreted by identifying pollution maps for each metal
Turkey – A country put aside and perceived to be “the other”, yet still alluring
Get PDFThis article explains the notion of the reconstruction in the man`s mental construct created by various information produced by different information tools. It can be said that the geopolitical perception would also change for this reconstruction. Geopolitical perception that Turkey currently has, has changed due to the relations with EU and social and political developments in the Middle East. Such a change also alters the societies` and countries` perception of political and global identity. Geopolitical thought necessitates the actualization of geography`s role in the intergovernmental relations. There is no uniformity between the state and public in Turkey about the matter of the global relations. But, the state cannot be accepted as a different unity from the society. It is thought that the relationships and developments will reconstruct the geopolitical perception, and in the end, it will bring a new stance. This stance may be an influential element and precursor of a new concept in the international relations that will last for years. 
Erosion risk analysis in Sapanca Lake Basin: Sapanca Gölü Havzası’nda erozyon risk analizi
Get PDFThe aim of this study is to determine the erosion susceptibility areas in the Sapanca Lake Basin. Sapanca Lake basin is located in the east of the Marmara Region. Due to its natural beauty, transportation opportunities and proximity to metropolitan areas, it is a preferred area for permanent and temporary living. Increasing population and growing settlement areas have created significant changes in the land cover, and depending on this situation, the erosion sensitivity of the research area has increased. In this study, Landsat 8 OLI satellite image dated 24.07.2022 was used to determine the land use status. RUSLE evaluates Precipitation Erosive (R), Soil Erosion Susceptibility (K), Slope Length and Slope Slope (LS), Ground Cover (C) and Erosion Control (P) Factors in Geographic Information Systems to determine the amount of soil loss. The Equation (Revised Universal Soil Loss Equation) method was applied. According to the RUSLE method, erosion susceptibility map of Sapanca Lake Basin was obtained and susceptibility classes were determined. These susceptibility classes are six categories: very light, mild, moderate, strong, severe and very severe. According to the map obtained, very light in 46.3% (13607.8 ha), mild in 7.5% (2211.5 ha), moderate in 15.3% (4493.8 ha), strong in 7.9% (2317.9 ha), Severe erosion susceptibility was detected in 9.8% (2864.1 ha) and very severe erosion sensitivity in 13.2% (3872.4 ha).The average annual soil loss is less than 5 tons/ha/year.The most sensitive areas in terms of the severity of erosion are the steep slopes of the Samanlı Mountains in the southand moderately sloping slopes in the north. The shores of Sapanca Lake and its surroundings are areas with slight erosion sensitivity. In addition to the effect of precipitation and soil characteristics on the land cover, the sloping areas opened to settlement due to human activities due to incorrect land use have increased the sensitivity of erosion. It is recommended to plan for a sustainable land use in the adaptation process to climate change, taking into account the areas susceptible to erosion.
Extended English summary is in the end of Full Text PDF (TURKISH) file.
Özet
Bu çalışmanın amacı Sapanca Gölü Havzası’nda erozyon duyarlılık alanlarının belirlenmesidir. Sapanca Gölü Havzası, Marmara Bölgesi’nin doğusunda yer alır. Doğal güzelliği, ulaşım imkanları ve metropolitan alanlara yakınlığı nedeniyle devamlı ve geçici bir süre yaşam için tercih edilen bir alandır. Artan nüfus ve büyüyen yerleşim alanları arazi örtüsünde önemli değişimler oluşturmuş bu duruma bağlı olarak araştırma alanının erozyon duyarlılığı artmıştır. Bu çalışmada arazi kullanım durumunu belirlemek için 24.07.2022 tarihli Landsat 8 OLI uydu görüntüsü kullanılmıştır. Toprak kaybı miktarını belirleyebilmek için Coğrafi Bilgi Sistemlerinde, Yağış Erozif (R), Toprak Erozyon Duyarlılığı (K), Eğim Uzunluğu ve Eğim Dikliği (LS), Zemin Örtüsü (C) ve Erozyon Kontrol (P) faktörlerini değerlendiren RUSLE (Düzenlenmiş Evrensel Toprak Kaybı) metodu (Revised Universal Soil Loss Equation) metodu uygulanmıştır. RUSLE yöntemine göre; Sapanca Gölü Havzası’nın erozyon duyarlılığı haritası elde edilerek, duyarlılık sınıfları belirlenmiştir. Bu duyarlılık sınıfları; çok hafif, hafif, orta, güçlü, şiddetli ve çok şiddetli olmak üzere altı sınıftan oluşur. Elde edilen haritaya göre inceleme alanının %46,3’ünde (13607.8 ha) çok hafif, %7,5’inde (2211.5 ha) hafif, %15,3’ünde (4493.8 ha) orta, %7,9’unda (2317.9 ha) güçlü, %9,8’inde (2864.1 ha) şiddetli ve %13,2’sinde (3872.4 ha) çok şiddetli erozyon duyarlılığı tespit edilmiştir. Yıllık ortalama toprak kaybı 5 ton/ha/yıldan azdır. Erozyonun şiddeti bakımından en duyarlı bölgeler güneyde Samanlı Dağları’nın dik yamaçları ile kuzeyde hafif ve orta eğimli yamaçlardır. Sapanca Gölü kıyıları ve çevresi hafif derecede erozyon duyarlılığı taşıyan alanlardır. Arazi örtüsünde yağış ve toprak özelliklerinin etkisi yanında yanlış arazi kullanımı sebebiyle insan faaliyetleri sonucu özellikle turizm ile yerleşmeye açılan eğimli alanlar erozyon duyarlılığını arttırmıştır. İklim değişikliğine uyum sürecinde sürdürülebilir bir arazi kullanımı için erozyona duyarlı alanlar dikkate alınarak planlama yapılması önerilmektedir.
Analysis of the changes in vegetation of the Sapanca Lake Basin (in Turkey) using multitemporal satellite data
Get PDFThe Lake Sapanca Basin is located in an area where urbanization and industrialization is rapidly increasing because of its geographical location. The Sapanca Lake Basin was opened to settlement densely after 1980 due to recreational activities for urbanization and industrialization. The aim of this study is to investigate and evaluate the changes in natural vegetation and settlement caused by the effects of human activities in the Sapanca Lake Basin. For this purpose, Landsat 5 TM (1987) and Landsat 8 (2013) satellite images have been used. These images have been analyzed using ERDAS and ArcGIS software’s and this was supported and confirmed by the carried land studies. The results showed that there has been an % 12.8 decrease in the high density green vegetation areas. It is concluded that the natural vegetation of Sapanca Lake Basin damaged rapidly in the period between the years of 1987-2013
Vegetation periods and changes in the Thrace (1965-2011)Trakya’da vejetasyon süreleri ve değişimleri (1965-2011)
Get PDFThe existence and distribution of plants on the earth with one of the most important elements of the natural environment are determined by the abiotic and biotic conditions. Changes that occur in natural conditions and human activities are generally creating a negative effect and many plant species are facing in danger of extinction. One of these conditions, climate is main factor that directly affects the lives of plants and determines the existence and distribution of vegetation as globally, regionally and locally.The greenhouse effect caused by human activities in the last century and the global climate change can have impacts on the existence and spatial changes of plants. In this context, the effects of temperature conditions as the main factor on vegetation are examined according to the certain temperature values and duration. Mean daily temperature values of meteorological stations, which have long term observation record, in the study area, were analyzed statistically. As a result, dates of start, dates of finish and number of days and temporal changes of vegetation period are determined in this period.Extended English abstract is in the end of PDF (TURKISH) file.ÖzetDoğal ortamın en önemli unsurlarından olan bitkilerin varlığını ve yeryüzündeki dağılışını abiyotik ve biyotik koşullar belirlemektedir. Doğal koşullarda meydana gelen değişimler ve insan faaliyetleri, genellikle olumsuz etki yaratmakta ve birçok bitki türünün nesli tükenme tehlikesiyle karşı karşıya kalmaktadır. Bu koşullar içerisinde iklim doğrudan bitki yaşamını etkileyen ana faktör durumunda olup küresel, bölgesel ve yerel olarak vejetasyon topluluklarının varlığını ve mekânsal dağılışını belirlemektedir.Son yüzyılda insan faaliyetlerine bağlı olarak ortaya çıkan sera etkisi ve küresel iklim değişimi bitkilerin varlığı ile mekânsal değişimi üzerinde etkili olabilmektedir. Bu çerçevede, vejetasyon üzerinde ana etken durumunda olan sıcaklık koşullarının bitkiler üzerindeki etkisi, belirli sıcaklık değerleri ve süresine göre ele alınıp incelenmiştir. İnceleme alanında uzun dönem gözlem kaydı bulunan meteoroloji istasyonlarının günlük ortalama sıcaklık verileri istatistiki olarak analiz edilmiştir. Sonuç olarak incelenen bu dönem içerisinde vejetasyon devresinin başlangıç, bitiş tarihleri ve gün sayıları ile zamansal değişimi belirlenmiştir
Analyzing land cover change using remote sensing and gis methods in the Carsamba Plain and its surroundings (1985-2013)Çarşamba Ovası ve yakın çevresinde arazi örtüsü değişiminin uzaktan algılama ve coğrafi bilgi sistemleriyle analizi (1985-2013)
Get PDFThe aim of this study is to analyze the change of land cover of Çarşamba Plain and its surroundings by remote sensing and geographic information systems. For this purpose, Landsat 5 TM image at a resolution of 30 km for the year 1985, and the RapidEye satellite image at 6.5 m. resolution,for the year 2013 is used. These images were analyzed by geographic information systems via on-screen digitization method. According to the results obtained, significant changes in the land cover of the survey area between 1985-2013 have been determined. These findings were compared with the Land Surveillance System, the National Land Cover Database, which was created by the T.C Forest and Water Affairs Ministry and similar results were obtained. It has ben determined that there ise a change in decreasing direction in the forest and pasture areas in the examined period. Also beach areas is getting smaller because of coastal eroision. However, settlement areas expanded due to population increase in the same period. ÖzetBu çalışmanın amacı Çarşamba Ovası ve yakın çevresinde arazi örtüsü değişimini uzaktan algılama ve coğrafi bilgi sistemleri kullanılarak analiz etmektir. Bu amaç doğrultusunda 1985 yılı için 30 km çözünürlüğünde Landsat 5 TM, 2013 yılı için 6.5 m. çözünürlüğünde RapidEye uydu görüntüsü kullanılmıştır. Bu görüntüler coğrafi bilgi sistemleri ile ekran üzerinden sayısallaştırma yöntemiyle analiz edilmiştir. Elde edilen sonuçlara göre, 1985-2013 yılları arasında araştırma alanının arazi örtüsünde önemli değişiklikler tespit edilmiştir. Bu bulgular, T.C Orman ve Su İşleri Bakanlığı tarafından oluşturulan Arazi İzleme Sistemi, Ulusal Arazi Örtüsü veri tabanı ile karşılaştırılmıştır
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