AYBE- İklim ve Deniz Bilimleri Lisansüstü Programı - Yüksek Lisans
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Yazar "Dalfes, Hasan Nüzhet" ile AYBE- İklim ve Deniz Bilimleri Lisansüstü Programı - Yüksek Lisans'a göz atma
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ÖgeDoğu Kayını (fagus Orientalis) Ağacının Alansal Dağılım Modellemesi: Geçmiş, Günümüz Ve Gelecek(Eurasia Institute of Earth Sciences, 2018-06-08) Dağtekin, Ayşegül Dilşad ; Dalfes, Hasan Nüzhet ; 601161010 ; Climate and Marine Sciences ; İklim ve Deniz Bilimleri Anabilim DalıClimate change affects forest biomes more severely than ever, even with the ~1°C temperature warming so far. Geographical distributions of these biomes are linked to warming temperatures and decreasing precipitation. Species try to adapt to this change by changing these geographical barriers. Recent warming not only impacted the survival rates of most tree species, also increased risks in handling extreme events. Fagus orientalis is a temperate, deciduous, broad-leaved species, which covers a wide area from the eastern Balkans through Turkey, Caucasia, Crimea and northern Iran, including the Amanos Mountains in the south, with a large elevational distribution from sea level to 2100 m. Beech has an important role in terms of dominating forests and creating new ecosystems, also it is used by many industries. Several research indicate that these species are disturbed by changing the climate in terms of increasing temperature and decreasing precipitation. Because of its importance in forestry, industry and ecosystem Fagus sp. were the focus of interest in this study. We conducted species distribution model simulations with five different algorithms embedded in biomod2 R package – BIOCLIM, GAM, GLM, RF, MaxEnt – and with environmental data from the climate of the present, past, and future from Wordclim version 1.4, as well as digital elevation model for altitude from NASA. Our simulations covered an area in Eurasia where Fagus sp. is seen, exact coordinates of 18 – 62 East and 33 – 51 North. We verified our model with present-day classifications, which fitted well the distributional data obtained from General Directorate of Forestry and EUFORGEN project. These models were used to 'predict' distributions through climate changes spanning Last Glacial Maximum (21,000 bp), Mid-Holocene (6,000 bp), 2050 and 2070 obtained from two global climate models, MIROC-ESM and CCSM4. We observed that F. orientalis distribution is toward the northeast from its present distribution, where mountainous regions are intense, colder and wetter climates are available according to future conditions. These results led us to verify that drier climate and higher temperatures are considered as limitations to these species. Additionally, we could identify refugia areas for this particular species in the past which might lead to new studies. We believe that the outcomes of this study would help improving management and conservation plans for Fagus orientalis in order to protect it from severe effects of climate change.
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Ögeİnsuyu Mağarasının Bakteriyel Ve Arkeal Biyoçeşitliliği(Eurasia Institute of Earth Sciences, 2016-11-25) Tok, Ezgi ; Dalfes, Hasan Nüzhet ; 601131009 ; Climate and Marine Sciences ; İklim ve Deniz Bilimleri Anabilim DalıCaves are one of the unique habitats to see interaction between rock and microbes. In the aspect of microbiological researches, caves are unique environments in order to not only the limitations on exposing to exterior environmental conditions but also the natural isolation for disturbants such as other living creatures. In these harsh environments, Proteobacteria, Actinobacteria, Chlorobi/Bacteriodetes, Chloroflexi, Deltaproteobacteria, Acidobacteria, Nitrospirae, Actinobacteria and Betaproteobacteria are the most common and diverse group of bacteria because of their adaptation ability. In this study, we conducted cultivation-independent 16S rDNA surveys on the bacterial and archaeal community of Insuyu Cave, Burdur, TURKEY. The complexity of microbial communities has been presented in samples through PCR amplification of the 16S ribosomal RNA (16S rRNA) gene sequence, high resolution melting curve (HRM) and next generation sequence (NGS) based on 16S rRNA metagenomics from a variety of cave samples to identify bacterial and archaeal community profile of Insuyu Cave. A total of nine known bacterial class were found within the context of this research (Figure 3.4). The most prevalent class is alphaproteobacteria with 89,23% of the total bacteria found grouping into four order, with the most abundant ones: rhizobiales (88,85%) and sphingomonadales (0,21%). The followings, ordered by abundancy, are actinobacteria (3,94%), bacilli (2,92%), gammaproteobacteria (1,69%) and betaproteobacteria (0,74%). Also, a total of fourteen genera from ten order were identified in this study (Figure 3.5). The most dominant is methylobacterium with 88,83%, from the class of rhizobiales (88,85%). The followings are propionibacterium (3,58%), dolosigranulum (1,69%), streptococcus (1,10%) and pseudomonas (1,13%). On the other hand, no Archaeal species has been detected at the result of NGS analysis while some archaeal nucleic acid had been marked as a result of PCR analysis. The reasons of this situation has been investigated in the section of discussion.
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ÖgeTürkiye Orman Fenolojisindeki Değişikliklerin Modıs Uydu Verileri Aracılığıyla İncelenmesi(Eurasia Institute of Earth Sciences, 2018-06-08) İpek, Yetkin ; Dalfes, Hasan Nüzhet ; 601161006 ; Climate and Marine Sciences ; İklim ve Deniz Bilimleri Anabilim DalıThe Start of Growing Season (SGS) marks the time of year where a type of plant starts its growing season; therefore, forming green leaves. The End of Growing Season (EGS) is the opposite, where plants end their growing seasons and start defoliation. The difference in green leaf changes are much more dramatic in deciduous forests than coniferous forests, all plants show annual differences after SGS and EGS. As all plants undergo SGS and EGS, they look for environmental cues in order to keep up with their annual cycles. To detect variations in SGS and EGS, MODIS imagery was used. MODIS satellites have a polar orbit and capture images in 7 spectral bands daily. To detect the SGS and EGS from MODIS satellite data by comparing the surface reflectance in red versus green through the GRVI index was used. The threshold for the detection of SGS and EGS is set to GRVI = 0. If GRVI > 0, then it is currently the growing season; if GRVI < 0 then it is the senescence season. Yearly GRVI estimates are analyzed to detect the SGS and EGS by catching GRVI zero crossing. We tried to detect the yearly shifts of SGS and EGS using this GRVI estimates. For these measurements, daily MODIS Terra MOD09GA V006 products were downloaded for the period 2007-2017, then analyzed through an R script using RASTER package. Noise reduction was applied on the results using Exponential Moving Average and the GRVI=0 crossings were detected. Later, the refined data were compared annually and among regions with different vegetation to look for SGS and EGS shifts over time. Although in all plots there were obvious peaks during Growing Season, in some cases of mountain ranges and coniferous forests, GRVI method was unable to detect SGS or EGS; as there was no 0 crossing. In the regions where GRVI was successful, SGS shifted to an earlier DOY and EGS shifted to a later DOY on a scale of 11 years. Overall, the GRVI has been successful in showing seasonal patterns in a given region.
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ÖgeTürkiye'deki Kuş Türleri Çeşitliliği Ve Habitatın Uzaktan Algıma Parametleri(Eurasia Institute of Earth Sciences, 2019-09-13) Lee, Sangji ; Dalfes, Hasan Nüzhet ; 601171004 ; Climate and Marine Sciences ; İklim ve Deniz Bilimleri Anabilim DalıEcosystems are large and difficult to access. Therefore, it is difficult to measure the biodiversity. However, The development of various remote sensing technologies makes ecosystem research easier and more accurate than ever before. In this thesis, MODIS was used in the main study of Turkey as a whole, and LiDAR was used in further studies in some parts of the Black Sea. It is inevitable that biodiversity is decreasing worldwide. Various natural and physical influences are changing the living place. This study was geared towards birds living in Turkey. Bird populations and species are also decreasing in Turkey due to environmental and climate changes. (boyla et al, 2019). This study identified the relationship between bird species richness and vegetation, which is considered a major habitat for birds. Several studies have already shown that they are positively correlated.(Liang et al, 2018; Seto et al, 2004) There is a need to identify Turkey as a case. I wanted to see if the relationship could be confirmed with the vegetation index, a single parameter. Analysis of the relationship between all bird species and vegetation observed in Turkey, including species that do not have vegetation as their habitat. Remote sensing data was used to obtain vegetation information. The study used NDVI and EVI via MODIS Terra. First, I mapped three years of changes in NDVI and EVI from 2015 to 2017 throughout Turkey. All of them decreased every year. The trend were similar, but EVI was generally lower than NDVI, as usual. The map shows that the vegetation of the central inland regions of Turkey is further reduced. To check the relationship with the obtained vegetation index, bird species data was extracted from Turkish Breeding bird atlas data during the same 2015-2017 period was identified. Both NDVI and EVI showed a positive correlation with the bird species data. Especially, the maximum value of NDVI correlated strongly with Bir Species Richness. And, the mean values were most correlated in EVI. It is believed that EVI is sensitive to the terrain. (Matsushita et al, 2007) In addition, the correlation with 2017 was highist. Even 2015 EVI was analyzed to be independent of bird species richness. It was found that the Species richness at the same time has changed with the decrease of vegetation. The results of this study provide an overall review of the positive correlation between bird species richness and vegetation in Turkey. Furthermore, the usefulness of NDVI and EVI was confirmed again. After the main research as above, to understand the forest area in some areas a more detailed study was attempted. Further research on forest structure and bird diversity in local areas has been conducted. I used light detection and ranging (LiDAR) to collect more accurate high-resolution data for forest structure analysis. The two forests of each 0.4 km wide and 10 km long are selected from the forests with high bird species richness and relatively low bird species richness and their structural analysis using the LiDAR poind cloud data and the CHMs classification which one of forest metrics greatest influence on birds habitat. In addition, I used forest management plans data to analyze the differences in specific tree types and growth levels in each region. Under the assumption that species observed in the Atlas square (50km x 50km), can live in or stay in all the forests in that square. The results were that CHM was similar in overall trend, but the region with high species richness of bird had a higher proportion of '10 -20m ' than the low species richness region. Through the DEM, I could find many ridgelines, including steep slopes in the region with high specie richness. In addition, The region of high specie richness of bird had more varieties of trees than low specie richness region. DBH proportion was '8-19.9cm' of non-thick trees was high. At the top crown closure level, it was confirmed that both areas were dense forests with a high degree of closure. It results show the effectiveness of LiDAR in assessing forest health and productivity, and assessing habitat quality. Continued research into forests and habitats using various techniques such as LiDAR can lead to the creation of appropriate wildlife habitat models to build ecological forest management. Comprehensive correlation analyzes between habitat and other factors, climate change and forest structure etc, are required. Climate and physical changes at the time of the change in vegetation should also be identified. In order to maintain biodiversity, further research should be conducted to identify what changes are being made to the ecosystem and why these changes have occurred.
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ÖgeÜniversite Öğrencilerinin Biyoçeşitlilik Algısı Ve Biyoçeşitlilikle İlgili Tutumlarının Analizi(Eurasia Institute of Earth Sciences, 2015-01-19) Şenel, Tuğçe ; Dalfes, Hasan Nüzhet ; 601111006 ; Climate and Marine Sciences ; İklim ve Deniz Bilimleri Anabilim DalıTurkey has a very rich biodiversity yet this enourmous richness is seriously under threat. Lack of nature education leads conservation acts and campaigns to be under supported and even rejected by people. To have a sufficient nature education is very important for young population, who are scientists, engineers, decision makers, law makers...etc. of the future. In Turkey, nature education basically consists of biology courses. In this study, two hundred higher education students were asked to participate in a twelve item questionnaire about biodiversity. Their perception and attitudes towards biodiversity were investigated. Results show that although the students know what biodiversity is and they are sensitive about environmental issues they have many confusions, misconceptions and lack of knowledge. Results also underline that, a well planned, early starting nature education which families also will be a part of it is required and this education should be seperated from biology courses and be a life long learning process.
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ÖgeBir Zebra Midyesi (dreissena Polymorpha) İstilasının Mekansal Ve Zamansal Örüntüleri(Eurasia Institute of Earth Sciences, 2015-01-19) Kanmaz, Oğuzhan ; Dalfes, Hasan Nüzhet ; 601111005 ; Climate and Marine Sciences ; İklim ve Deniz Bilimleri Anabilim DalıBiological invasions are an important dimension of global change and is an environmental problem which has a serious consequences. Awareness about this issue has increased, especially after the invasion of zebra mussels in Great Lakes of North America and environmental and economic results of this invasion. In this study, spatial and temporal patterns of the zebra mussel invasion in Great Lakes was studied, for a 20-year period by using individual based modelling method. The model was developed in NetLogo environment. Numerical experiments were also conducted in this environment. First of six experiment sets is reference case experiment. Effects of phytoplankton density on zebra mussel populations were investigated in P75 and P125 experiment sets. In T0.1 and T10 experiment sets, effects of transportation probability on zebra mussels were investigated. Last experiment set, SupD, was conducted to observe how environmental changes would affect a biological invasion, by applying Lake Huron conditions to Lake Superior. According to results, there is no linear relation between the change of phytoplankton amount and the increase of zebra mussel population and slight changes of phytoplankton amount cause significant increases in invasion strenght. Changes in transportation probability, affect invasion stages temporally and also have impact on population size. SupD experiment results show that probable climate changes have a strengthening effect on biological invasions. Results also show that, lake location in the waterbody network is also important beside the individual conditions of each lake and mussel populations constitute characteristic patterns depending on invasion strenght.