Kent içi arkeolojik alanlarda katmanlaşmanın analizi ve koruma sorunları: Foça örneği

Foça Batı Anadolu’da Prehistorik dönemden başlayarak Arkaik, Klasik, Helenistik, Roma, Bizans, Ceneviz kolonisi ve Osmanlı dönemlerinde sürekli iskân görmüş, çok katmanlı bir yerleşimdir. Kentte arkeolojik kazı çalışmaları 20. yüzyıl başından günümüze aralıklarla devam etmektedir. Üçüncü dönem kazı çalışmaları Prof. Dr. Ömer Özyiğit başkanlığında 1989 yılından beri sürmektedir. Modern Foça kenti, tarihi yaklaşık M.Ö. 3000’lere dek uzanan antik Phokaia kentinin üstünde bir katman olarak bulunmakta ve kazı çalışmaları da kent içi arkeolojik alanlarda yoğunlaşmaktadır. Kentin tarihi katmanlaşmasında en üst tabaka olarak Osmanlı dönemi sivil mimarlık örnekleri öne çıkmaktadır. Bununla birlikte modern kent dokusunu az katlı, niteliksiz betonarme yapılar oluşturmaktadır. Kentte ilk sit kararlarının belirlendiği 1977 yılından günümüze dek sit sınırları pek çok kez değişmiş ve bu durum yeni yapılaşmanın önünü açmıştır. Özellikle turizmin ve ikincil konut yapımının artması ise kültür varlıklarına zarar vermiştir. Bu olumsuz durum kent içi arkeolojik alanlarda katmanlaşmanın zarar görmemesi için farklı yaklaşımlara gereksinim duyulduğunu göstermektedir. Kentsel arkeoloji çalışmaları bu gereksinime yanıt verecek nitelikte olup, kapsamlı tarih araştırmaları ile desteklenen kazı çalışmalarında ortaya çıkan verilerin, kentlerin koruma, planlama ve gelişim süreçlerine eklenmesini öngörmektedir

Multi-proxy palaeoecological responses to water-level fluctuations in three shallow Turkish lakes

Natural or human-induced water-level fluctuations influence the structure and function of shallow lakes, especially in semi-arid to arid climate regions. In order to reliably interpret the effect of water-level changes from sedimentary remains in the absence of historical data, it is crucial to understand the variation in sedimentary proxies in relation to water level measurements. Here, we took advantage of existing water surface elevation data on three large shallow lakes in Turkey to elucidate the impact of lake-level changes on benthic-pelagic primary production over the last 50-100 years. Sub-fossil cladocerans, diatoms, plant remains and pigments were investigated as biological variables; X-ray fluorescence (XRF) and loss on ignition (LOI) analyses were conducted as geochemical-physical variables on a set of Pb-210 and Cs-137 dated cores. Dating of the cores were robust, with the exception of uncertainties in Lake Marmara littoral core due to low unsupported 210Pb activities and high counting errors. Results indicated that Lake Marmara was dominated by benthic species throughout the sediment record, while Lakes Beysehir and Uluabat shifted from a littoral-dominated system to one with increased pelagic species abundance. In all cores there was a stronger response to longer-term (decadal) and pronounced water-level changes than to short-term (annual-biennial) and subtle changes. It was also noted that degree of alteration in proxies differed between lakes, through time and among pelagic-littoral areas, likely emphasising differences in depositional environments and/or resolution of sampling and effects of other stressors such as eutrophication. Our results highlight lake-specific changes associated with water-level fluctuations, difficulties of conducting studies at required resolution in lakes with rather mixed sediment records and complexity of palaeolimnological studies covering recent periods where multiple drivers are in force. They further emphasise the need to include instrumental records when interpreting effects of recent water-level changes from sediment core data in large shallow lakes

Impact of nutrients and water level changes on submerged macrophytes along a temperature gradient: A pan-European mesocosm experiment

Submerged macrophytes are of key importance for the structure and functioning of shallow lakes and can be decisive for maintaining them in a clear water state. The ongoing climate change affects the macrophytes through changes in temperature and precipitation, causing variations in nutrient load, water level and light availability. To investigate how these factors jointly determine macrophyte dominance and growth, we conducted a highly standardized pan-European experiment involving the installation of mesocosms in lakes. The experimental design consisted of mesotrophic and eutrophic nutrient conditions at 1 m (shallow) and 2 m (deep) depth along a latitudinal temperature gradient with average water temperatures ranging from 14.9 to 23.9 degrees C (Sweden to Greece) and a natural drop in water levels in the warmest countries (Greece and Turkey). We determined percent plant volume inhabited (PVI) of submerged macrophytes on a monthly basis for 5 months and dry weight at the end of the experiment. Over the temperature gradient, PVI was highest in the shallow mesotrophic mesocosms followed by intermediate levels in the shallow eutrophic and deep mesotrophic mesocosms, and lowest levels in the deep eutrophic mesocosms. We identified three pathways along which water temperature likely affected PVI, exhibiting (a) a direct positive effect if light was not limiting; (b) an indirect positive effect due to an evaporation-driven water level reduction, causing a nonlinear increase in mean available light; and (c) an indirect negative effect through algal growth and, thus, high light attenuation under eutrophic conditions. We conclude that high temperatures combined with a temperature-mediated water level decrease can counterbalance the negative effects of eutrophic conditions on macrophytes by enhancing the light availability. While a water level reduction can promote macrophyte dominance, an extreme reduction will likely decrease macrophyte biomass and, consequently, their capacity to function as a carbon store and food source

Temperature Effects Explain Continental Scale Distribution of Cyanobacterial Toxins

Insight into how environmental change determines the production and distribution of cyanobacterial toxins is necessary for risk assessment. Management guidelines currently focus on hepatotoxins (microcystins). Increasing attention is given to other classes, such as neurotoxins (e.g., anatoxin-a) and cytotoxins (e.g., cylindrospermopsin) due to their potency. Most studies examine the relationship between individual toxin variants and environmental factors, such as nutrients, temperature and light. In summer 2015, we collected samples across Europe to investigate the effect of nutrient and temperature gradients on the variability of toxin production at a continental scale. Direct and indirect effects of temperature were the main drivers of the spatial distribution in the toxins produced by the cyanobacterial community, the toxin concentrations and toxin quota. Generalized linear models showed that a Toxin Diversity Index (TDI) increased with latitude, while it decreased with water stability. Increases in TDI were explained through a significant increase in toxin variants such as MC-YR, anatoxin and cylindrospermopsin, accompanied by a decreasing presence of MC-LR. While global warming continues, the direct and indirect effects of increased lake temperatures will drive changes in the distribution of cyanobacterial toxins in Europe, potentially promoting selection of a few highly toxic species or strains.Peer reviewe

Ötrofikasyon ve su seviyesi değişiminin Türkiye’de bulunan sığ göller üzerindeki etkileri: bitki kalıntıları ve pigmentler ile palaeolimnolojik bir yaklaşım.

Current study provides further understanding of plant macrofossil and sedimentary pigment utilization in comparison with modern and historical environmental variables. Moreover, it contributes to investigations for determining suitable macrophyte-based indices (water framework directive-WFD) that can be employed in Turkey. In total 44 small and mostly shallow lakes, covering the whole latitudinal gradient at western half of Turkey were sampled with snap-shot sampling and from another set of three large lakes cores were retrieved. Plant remains and pigments acquired from surface sediment samples showed significant accord to present-day plant and phytoplankton assemblages, respectively. Conductivity and trophic state were key environmental variables correlated with plants, also temperature and nutrients with phytoplanktonkton. Comparison of instrumental water-level data (40-100 years) with core samples from three lakes showed that effect of longer-term and pronounced water-level changes reflected in sediment record. Furthermore, employing plant remains in macrophyte-indice calculations increased the reliability of the results, which suggested that for shallow lakes, metrics based on species scores (including plant remains), and for deep lakes metrics using colonization depth may be more suitable. Being particularly useful for lakes in Mediterranean regions, that are especially vulnerable to hydrological constraints under climate change, these comparisons were conducted for the first time in Turkish shallow lakes and this study confirmed that sedimentary plant and phytoplankton remains are reliable indicators of environmental change. Furthermore, importance of conductivity, nutrients and temperature underpins the concerns on salinisation and eutrophication in Mediterranean region, supporting exacerbation of these problems as predicted by climate change projections.Ph.D. - Doctoral Progra

Effect Of Privacy On And Elements Of Identity In Muslim-Turkish Houses In Anatolia

“Culture” has a featured place among a large number of factors which are effective on the formation of house architecture. From time to time, it is observed that very different houses are formed in the same physical environment. Sometimes analogous houses can be seen under highly different environmental conditions. It is possible to mention the effects of different cultures and lifestyles on this.The study aims to reveal how the effect of privacy is reflected in spatial formation and architectural elements in Muslim-Turkish houses. The relationship of the Turkish House with the concepts of Ottoman, Anatolia, Muslim and tradition as well as coincidence and variations are addressed. The analytical and comparative method is employed in the study. The common elements in the architectural formation which are caused by the vital and cultural interactions in the Turkish houses in Anatolia and the Balkans are reflected in the form of analogies in the building façade character and in architectural elements. It is possible to gather the analogies in the Turkish houses not only in the context of Anatolia and the Balkans but also at different corners of Anatolia under the common ground of “culture”. The effects of culture are reflected in the house architecture in a wide range from the use of lattice in various spaces and elements to kapı şakşaks besides the openings which vary on the building façades depending on location and story.In this study, the concept of Turkish House and the thorough investigations into this issue are considered and the effect of the factor of “privacy” on the formation of Muslim-Turkish houses in Anatolia is examined from different perspectives. The subject is presented via the examples of Turkish houses selected from various localities of Anatolia. How the inward character of the Turkish house and its understanding of privacy are reflected in the details of an architectural building besides its façade and spatial construct is conveyed via examples.The thorough investigation concerned is of importance to see how culture and lifestyle are reflected on architecture – in other words, to read culture from the formation of a house.

Ülkemiz sığ göllerindeki geçmiş sucul bitki dinamiğinin ve ekosistem durumunun paleolimnolojik yöntemler kullanılarak değerlendirilmesi.

Since submerged macrophytes are a key primary producer of shallow lakes and are sensitive to environmental changes, macrofossils of them can be used in investigations of past environmental conditions, to infer human introduced environmental impacts (e.g. eutrophication) and to determine past macrophyte communities. The present study includes twenty six shallow lakes, which were chosen along a latitudinal gradient ranging from the North (41°52́N, 27°58́E) to the South (37°06́N, 29°36́E) in Turkey. Sampling for environmental variables and sediment was carried out using a snap-shot sampling protocol (developed within the framework of the EU FP6 project ‘Eurolimpacs’) during the summers of three consecutive years (2006-2008). Surface sediment, short core and long core samples were retrieved from the lakes. The aims of this study were i. to compare the surface sediment plant macrofossils with present day macrophyte taxa of the lakes, ii. to determine the environmental variables potentially influencing the temporal changes in macrophyte communities, and iii. to assess vegetation community dynamics in dated short and long cores. Comparison of plant macrofossil assemblages in surface sediment with present day macrophyte coverage revealed that approximately 41% of the modern taxa were represented among the surface sediment macrofossils. Redundancy analysis (RDA) was carried out for surface macrofossil data with corresponding environmental data. RDA revealed relation of plant species and environmental variables (e.g. Salinity and Najas marina L.). Changes in plant species assemblages in short and long cores from eight lakes chosen along a latitudinal gradient ranging from North to South Turkey is discussed in relation to the RDA results.M.S. - Master of Scienc