Southern Marmara Research Articles

Clay mineral distribution in last Glacial-Holocene sediment cores from the eastern Marmara Sea (Çınarcık Basin–İzmit Gulf Transition), NW-Turkey: Multisources and transport paths in a two-way flow system

The regional variations in grain size, XRD-bulk and clay mineral distribution in 97 sediment samples from 6 gravity cores obtained from 20 to 300 m water depths have been investigated to reveal source and transportation patterns as well as the effects of climatic and sea-level changes during the last 25,000 14C BP in the eastern Marmara Sea (EMS), NW Turkey. The major proportions of sediments in the EMS consist of silt (20–83%) and clay (17–90%), whereas sand and gravel abundances rarely exceed 10%. Of the bulk minerals, 10-Å micas (23–55%) and feldspars (17–55%) dominate over quartz (10–21%) and calcite (10–26%). Smectites (23–62%), illite (18–36%), chlorites (6–21%), kaolinite (2–20%) and 14S–14C mixed layer minerals (0–27%) constitute the principal clay mineral assemblages. Both bulk and clay mineral assemblages in the EMS are similar to those found in the İzmit Gulf, on the southern Marmara shelf, at the Marmara–Aegean approaches and the southern Black Sea. This would suggest that there is no distinct source for mineral assemblages of the study area outside the Marmara Basin. The concentrations of clay fractions and clay mineral assemblages tend to increase or decrease with depth in the cores, but this is limited to some intervals and not to entire sections in the cores. This distribution pattern therefore represents rather local sources of provenance and surrounding fluvial drainage basins together with dilution and distribution effects by current transport processes, rather than the expected paleoclimatic features and sedimentary input by inflowing Black Sea and Aegean Sea water masses throughout the last Glacial to Holocene.

Soil Seed Bank and Aboveground Vegetation in Grazing Lands of Southern Marmara, Turkey

The composition and conservation of plant communities is greatly influenced by the soil seed bank. Information on the soil seed banks and the remaining vegetation in these ecosystems is crucial for guiding the restoration efforts. This study examines the size, species richness, diversity, uniformity, and similarity of soil seed banks and aboveground vegetation in 6 different grazing lands including coastal pasture, reseeded pasture, artificial pasture, lowland shrubland, ungrazed pasture, and hillside shrubland. Forty-eight soil samples were taken by cores with a diameter and depth of 10 cm from each of grazing lands in August of 2007. A vegetation survey was conducted using a 0.5 x 0.5-m quadrant in both the spring and fall. Eighty species were observed in soil seed banks and aboveground vegetation. The largest seed bank was observed in reseeded pasture (7,715 seed/m2), while the smallest seed bank was found in coastal pasture (2,755 seed/m2). Coastal pasture also possessed the least amount of aboveground vegetation (131 plants/m2). The most aboveground vegetation was found in ungrazed pasture (155 plants/m2). The most common species in seed banks were annual and perennial grasses in reseeded pasture, annual forbs in artificial pasture and hillside shrubland, and perennial forbs in low shrubland and ungrazed pasture. Species richness, diversity, and uniformity in seed banks were highest in lowland shrubland and lowest in artificial pasture. The seed bank and aboveground vegetation were similar in ungrazed pasture, coastal pasture, reseeded pasture, low shrubland, hillside shrubland and artificial pasture. Shrublands play an important role in species richness and the number of germinated seeds from seed banks of grazing lands in southern Marmara. The results showed that reseeding or a decrease in grazing pressure may improve the condition of grazing lands.

Proximate and Elemental Composition of Chamelea gallina from the Southern Coast of the Marmara Sea (Turkey)

The venerid clam Chamelea gallina is a popular and economic foodstuff around the Mediterranean countries especially in Italy, Spain, and France. The aim of this study is to evaluate the nutritional quality of striped venus of Southern Marmara. Samples were harvested seasonally at five stations and analyzed to determine meat yield, proximate, and elemental composition. According to the results, meat yield ranged from 20.24% to 29.94%. Means of water, protein, lipid, and ash content were 67%, 10.12%, 2.57%, and 1.66%, respectively. The mean concentrations (mg/kg wet weight) of elements in tissues are as follows: B: 2.37-4.24; Cr: 0-0.76; Co: 0-0.43; Cu: 0.71-5.30; Mn: 0.30-5.94; Zn: 13.08-77.76; Ni: 0-1.22; Fe: 2.46-114.22; Al: 1.23-75.49; Pb: 0.18-3.24; Ba: 0.66-15.97; Cd: 0.04-0.69. Among the reported metal levels, only Pb and Zn in two stations exceeded the maximum critical concentrations enforced by Turkish legislation and European Commission. Therefore, we report that striped venus from Southern Marmara Sea, in general, are safe for human consumption; nonetheless, Pb and Zn levels should be closely monitored in the future.

Reviewing the geomorphologic and neotectonic features of the Gönen Basin (NW of Turkey)

The tectonic movements played a very important role of the formation of the Gönen Basin. During Quaternary period many dip and strike slip faults ocurred in the area. These faults affected the geomorphology and drainage system of the basin. The aim of this study is to determine the role of the tectonic activities occurred during the Quaternary period in forming the Gönen basin which is the one of the depressions on the southern Marmara Region on the northwest of Turkey. The tectonic movements formed the geomorphic units such as, depressions, scarps, off-set river channels, graben, horst, caused the deformation of surfaces. The faults affected the landscape and had important role the forming of the present drainage system. Hot springs came out along the fault lines. The down and up faultings accelerated the morphodynamics of the rivers, hence the erosional and depositional activities increased.

Determining Possible Relationships between Yield and Yield-Related Components in Forage Maize (Zea mays L.) Using Correlation and Path Analyses

This study was carried out to determine the optimum plant density and nitrogen rate in maize (Zea mays L.) under the ecological conditions of the Southern Marmara Region. For this purpose, maize was grown at different plant densities and was fertilized with different rates of nitrogen during 2006 and 2007. The dry forage yield, plant height, first ear height, stem diameter, leaf number plant-1, ear number plant-1, leaf ratio, stem ratio, ear ratio, ear diameter, leaf area index, and light interception were measured for all the treatments applied. The values of each parameter mentioned above were reorganized without regard to treatments or with regard to the highest and lowest values of plant density and nitrogen rates and were evaluated to determine the relationships between the dry forage yield and yield-related components. For this purpose, the direct and indirect effects of the corresponding components on dry forage yield were determined by using correlation and path analyses methods. The data averaged over two years, regardless of the treatment effects indicated that the relationship between the dry forage yield and each yield component except for stem ratio was positively significant. Path analysis revealed that most of the yield components had direct effects on the dry forage yield. According to this study, greater priority must be given to first ear height, leaf ratio and light interception to optimize silage maize yield. When the highest and the lowest plant densities and nitrogen rates were considered, it was understood that the nitrogen application had a greater effect on the dry forage yield than the plant density did.

Late Quaternary evolution of the Çanakkale Strait region (Dardanelles, NW Turkey): implications of a major erosional event for the postglacial Mediterranean-Marmara Sea connection

Seismic and bathymetric data from the Canakkale Strait and its extensions onto the shelves of the Marmara and Aegean seas indicate that the strait was formed mainly by an erosional event. Four seismic units are observed on seismic profiles. The lower two of these (units 4 and 3) constitute the basement of a regionally widespread erosional unconformity (ravinement), which developed during marine isotope stage 2 (MIS 2). The two upper units (units 2 and 1), which overlie the ravinement surface, form a higher-order sequence. Sequence stratigraphic analysis indicates that units 2 and 1 deposited as lowstand and highstand systems tracts respectively, since the end of MIS 2. The transgressive systems tract is represented by a major erosional event which occurred throughout the Canakkale sill area when the Mediterranean-Marmara Sea connection and, hence, the Canakkale Strait was formed. The existence of the erosive Şarkoy Canyon along the shelf edge of the southern Marmara Sea demonstrates that the flow direction causing the erosion was from south to north, thus proving that it was produced by Mediterranean water flowing over the sill into the Marmara Sea basin.

Genotype by environment interactions, stability, and heritability of seed yield and certain agronomical traits in soybean [Glycine max (L.) Merr.

This research was aimed to (1) evaluate genotypic yield performances of eight soybean genotypes, (2) determine their stability parameters and (3) estimate variance components and heritabilities of yield and yield-related traits. Eight soybean genotypes were evaluated in two locations (Mustafakemalpasa and Gorukle) of Southern Marmara Region, Turkey during two years (2000 and 2001), to identify patterns of genotype by environment interactions and their stabilities in terms of seed yield and yield-related components. Seed yield and its components are affected by plant genotype and environmental conditions. Plot data for plant height, first pod height, number of pods per plant, number of seeds per plant, number of seeds per pod, 1000 seed weight and seed yield were observed at all the four trials. There were significant differences between genotypes of one or two years at each location for all the traits. Significant differences among years or between locations were obtained in terms of all traits. Genotype x environment interactions at all the traits were highly significant. Thus the stabilities of eight soybean genotypes were different for all the traits. According to the stability parameters, none of the genotypes were stable for seed yield. Genotypes, Hodgson-78, A-3127, Ataem-1, Corsoy and SA-88 were considered as having high adaptability to good environments while Mitchell, Ataem-2 and Etae-8 adapted to poor conditions in terms of seed yield. Genetical components of variance at all the traits were highly significant. Genotype x location x year interaction variances were also found significant at all the traits except first pod height. The estimates of heritabilities with limited phenotypic variance definition were 0.14, 0.14, 0.21, 0.004, 0.13, 0.30 and 0.26 for plant height, number of seeds per pod, 1000 seed weight, first pod height, number of seeds per plant, number of pods per plant and seed yield, respectively. The heritabilities with complete phenotypic variance definition were 0.05, 0.05, 0.04, 0.003, 0.07, 0.19 and 0.20 for the same traits, respectively. Moderate or low heritabilities estimated for all the traits showed that family selection method could be used instead of individual selection in the breeding programs for improving seed yield and its components.

SSR analysis demonstrates that olive production in the southern Marmara region in Turkey uses a single genotype

The southern Marmara region in Turkey was surveyed to determine the olive cultivars that are used for olive production. Genetic diversity analysis using simple sequence repeat (SSR) markers indicated that the cultivar Gemlik is the major olive cultivar grown in this region, while other olive cultivars are grown only for use as pollinators of Gemlik or for growers' own exotic consumption. Although the quality of Gemlik is widely accepted in Turkey, its tendency toward alternate bearing is a major drawback. Twenty-four genotypes were selected within the cultivar Gemlik because of their tolerance to alternate bearing. These selected genotypes have the same SSR alleles as Gemlik, making them good candidates for developing a Gemlik olive with reduced alternate bearing. About 8% of samples did not share the same SSR alleles with Gemlik, though these genotypes were identified as Gemlik by the growers. Some other standard cultivars that are grown in other regions of Turkey were mistakenly called Gemlik in this region, probably due to the popularity of this cultivar in the southern Marmara region. In conclusion, as indicated by SSR analysis, Gemlik has become the standard cultivar in this region; future research should be focused on techniques to improve the production and quality of table olives and olive oil from this cultivar.

Erythromycin residue in honey from the Southern Marmara region of Turkey

Honey samples, collected from the Southern Marmara region of Turkey, were analysed for erythromycin residues by liquid chromatography–mass spectrometry using electrospray ionization in the positive ion mode (LC–ESI–MS). Fifty samples, comprising chestnut, pine, linden and multi-flower honeys, were collected directly from hives and analyzed. The limit of detection and quantification were 6 and 20 ng g−1, respectively, and recovery ranged from 85 to 89%. Four of the honey samples (8%) were found to be contaminated with erythromycin residues at concentrations ranging from 50 to 1776 ng g−1. An erythromycin-fortified cake feeding assay was also performed in a defined hive to test the transfer of erythromycin residue to the honey matrix. In this test hive, the residue level in the honey, 3 months after dosing, was approximately 28 ng g−1.

Seroprevalence of Q fever (coxiellosis) in sheep from the Southern Marmara Region, Turkey

Little information is available in Turkey on Q fever, a zoonose caused by Coxiella burnetii and transmitted from domestic ruminants. This study aimed at investigating the seroprevalence in sheep flocks from three provinces (Bursa, Balikesir and Canakkale). Serosurvey was undertaken on 42 flocks, which were categorised by sizes. Sera were collected randomly from specific age groups within the young population. CHEKIT Q-fever ELISA kit was used to identify the infection in sheep. The results showed that 20% (n=151) of sheep were seropositive. A total of 34 flocks (81%) revealed at least one seropositive animal. Higher seroprevalence was observed in Balikesir region. Larger flocks resulted more infected than medium and small flocks. An association was found between seropositivity and age, when the primiparous ewes (1-year old) had higher antibodies rates than newborn sheep (aged less than 10 months) or biparous ewes (2 years old). These results showed that Q fever infection was common and circulating in the studied region, hence encourage efforts to propose measures that could reduce the spread and the zoonotic risk.

Deficit Irrigation of Soya Bean [Glycine max (L.) Merr.] in a Sub‐humid Climate

AbstractAn experiment was conducted to investigate the influence of different levels of water deficit on yield and crop water requirement of soya beans in a sub‐humid environment (Southern Marmara region, Bursa, Turkey) in 2005 and 2006. One full‐irrigated treatment (T1), one non‐irrigated treatment (T5) and three different deficit irrigation (T2 = 25 % water deficit, T3 = 50 % water deficit, T4 = 75 % water deficit) treatments were applied to ‘Nova’ soya bean planted on a clay soil. Non‐irrigated and all deficit irrigation treatments significantly reduced biomass and seed yield and yield components. The full‐irrigated (T1) treatment had the highest yield (3760 kg ha−1), while the non‐irrigated (T5) treatment had the lowest yield (2069 kg ha−1), a 45.0 % seed yield reduction. T2, T3 and T4 deficit irrigation treatments produced 11.7–27.4 % less seed yield than the T1 treatment. Harvest index showed less and irregular variation among irrigation treatments. Both leaf area per plant and leaf area index were significantly reduced at all growth stages as amount of irrigation water was decreased. Evapotranspiration increased with increased amounts of irrigation water supplied. Our results indicate that higher amounts of irrigation resulted in higher seed yield, whereas water use efficiency and irrigation water use efficiency values decreased when irrigation amount increased.

Frequency of atopy and allergic disorders among adults with Type 1 diabetes mellitus in the southern Marmara region of Turkey

Autoimmune disorders are considered to be associated with a Th1 immune response whereas allergic diseases with a Th2 response. Studies mainly performed on children revealed conflicting results regarding the association of atopy/allergic disease and autoimmune disorders. Therefore, we aimed to investigate the prevalence of allergic diseases in adult Type 1 diabetic patients. Eighty-nine Type 1 diabetic patients and 64 controls were enrolled into the study. Skin-prick test and European Community Respiratory Health Survey questionnaire were performed on all cases. Patients who gave at least one positive answer to questions about asthma in the questionnaire underwent pulmonary function test and methacholine challenge test. Patients' mean age were similar in diabetic patients and controls (28.2+/-8.9 and 28.1+/-5.2 yr; respectively). In skin-prick test, the rate of positive response to at least one allergen was not significantly different in diabetes (29.2%) and in the control group (31.3%). In European Community Respiratory Health Survey questionnaire, diabetic patients waked up by an attack of cough more than controls did. The rate of physician-diagnosed asthma was similar in both groups. There was no difference between the 2 groups based on the answers of other questions about asthma and other allergic diseases such as allergic rhinitis, eczema, and drug allergy. We found that atopy frequencies were similar in an adult population of Type 1 diabetic patients and controls. Although asthmatic symptom prevalence is increased in diabetic patients, the incidence of current asthma was similar in both groups.

Comparison of the effects of different crop rotation systems on winter wheat and sunflower under rain-fed conditions

The study was made to detect the most suitable crop rotation system(s) under rain-fed conditions of Southern Marmara Region, Turkey. In this study (1995-2001), two different crop rotation systems were carried out: winter wheat and sunflower as main crops experiments. Results were evaluated in terms of crop yielding ability, soil fertility and economic aspects. The sunflower-rapeseed-wheat, rapeseedfodder pea + sunflower-wheat and rapeseed-common vetch + sunflower-wheat were found the most suitable rotation systems because of their various advantages in the first experiment in which wheat was used as main the crop. The highest sunflower seed yields were obtained from a fodder pea +sunflower-wheat-fodder pea + sunflower crop rotation system both in the first and second three year periods in which sunflower was used as main crop under rain-fed conditions. Economic analysis based on the second three-year results of the research showed that the highest mean net returns were obtained from the rapeseed-common vetch + sunflower-wheat and a fodder pea + sunflower-wheatfodder pea + sunflower crop rotation systems under rain-fed conditions. These crop rotation systems were found the best crop rotation systems under rain-fed conditions of Southern Marmara region of Turkey. As a result, the rotation systems including common vetch and fodder peas as forage plants under rain-fed conditions gave economically the highest net profit.

Therapeutic plasma exchange plus corticosteroid for the treatment of the thrombotic thrombocytopenic purpura: A single institutional experience in the southern Marmara region of Turkey

Thrombotic thrombocytopenic purpura (TTP) is a classic, but not a common disorder of hematology. Plasma exchange (PE) was shown to nearly reverse its 90% mortality rate. However, there are still some fatal outcomes in this dramatic disease. We present our experience of plasma exchange plus corticosteroids for the treatment of TTP in our hospital. Patients with TTP diagnosed between January 1996 and January 2005 were identified by a retrospective review of records of the Uludag University Hospital, Bursa (the largest referral center for adults with this disorder in this region with an estimated 2.2 million residents), which performs all therapeutic PE in the southern Marmara region in Turkey. A total of 11 (6 male, 5 female) patients were treated for TTP during this period. The median age was 39 years (range 18–49). One plasma volume exchange daily plus steroid was the principle treatment in all patients. A total of 295 PE sessions were performed. We have obtained six complete responses (CR) and three partial responses (PR) with daily PE and steroid (response rate 9/11). One of our primary refractory patients was saved with pulse steroid + cyclosporine + vincristine. Now, he is disease free for over one year. The other refractory patient did not develop any response to salvage therapy and expired on day 15 with status epilepticus and ventilator related pneumonia (mortality rate 1/11). A CR was obtained with adjuvant treatments in all three PR patients. Only one CR patient developed an early relapse (early relapse rate in CR patients 1/6). She was treated successfully with daily PE plus vincristine. Our median follow up period was 25 months (range 9–108). Considering our local population, our annual incidence is only about 0.63 new cases per one million people. This figure is considerably less than the data from US, which indicated an incidence of 3.7 cases per 1,000,000. To our knowledge, there is no high variability in the incidence of TTP in the different geographical regions of the world. It suggests that considerable number of patients escaped notice. We hope that, demonstrating the successful outcome, this article serves to urge primary physicians to keep in mind the diagnosis of TTP and refer suspected cases quickly.

The Effects of Different Row Spaces and Seeding Rates on the Hay and Crude Protein Yields of Sainfoin (Onobrychis sativa Lam.)

1 Necmettin CELIK 2 Gelis Tarihi: 02.03.2006 Abstract: The study was carried out to investigate the effects of different row spaces (15, 30, 45, 60 and 75 cm) and seeding rates (40, 80, 120, 160 and 200 kg ha -1 ) on the hay and crude protein yields of sainfoin at the Agricultural Research and Experiment Center of Agriculture Faculty, Uludag University in 1999-2002. The field experiments were established in a split plot design with four replications. Plant height, stem number per m 2 , green matter yield, hay yield and crude protein yields were determined. The results suggested that sainfoin should be planted with 15-30 cm row spaces and at 160-200 kg ha seeding rate for hay production in Southern Marmara Region or in regions with similar ecological conditions.

Boron content of Lake Ulubat sediment: A key to interpret the morphological history of NW Anatolia, Turkey

Freshwater Lake Ulubat (c. 1.5 m deep and c. 138 km 2) receives sediment from a 10.414 km 2 area in the seismically active Susurluk Drainage Basin (SDB) of NW Turkey. The B and trace element contents of the lake infill seem to be a link between the fresh landforms of the SDB and the lacustrine sediment. Deposition in Lake Ulubat has been 1.60 cm a −1 for the last 50 a according to radionucleides; however the sedimentation rate over the last millennium was 0.37 cm a −1 based on 14C dating. The B content of the lacustrine infill displays a slight increase at 0.50 m and a drastic increase at 4 m depth occurring c. 31 a and c. 1070 a ago, respectively. Probably the topmost change corresponds to the start of open mining in the SDB and the second one to the natural trenching of borate ore-deposits. These dates also show indirectly a 1.4 cm a −1 erosion rate during the last millennium as the borate beds were trenched up to 15 m. By extrapolation, it is possible to establish that the formation of some of the present morphological features of the southern Marmara region, especially river incision, began in the late Pleistocene, and developed especially over the last 75 ka.

Source of the basinal sediments in the Marmara Sea investigated using heavy minerals in the modern beach sands

The source of Recent turbidites in the deep basins of the Marmara Sea was investigated by comparing their heavy-mineral composition with those from the beach sands of the Marmara Sea. The Marmara Sea is an inland sea between the Mediterranean and Black seas. It consists essentially of three strike–slip basins, over 1000 m deep, which are forming along the North Anatolian Fault. The thickness of the Pliocene to Recent syn-transform sediments in the Marmara basins exceeds several kilometers. Sand samples were studied at 49 locations along the Marmara Sea beaches and in 15 samples from seven cores from the basins. Based on the amount and type of heavy minerals, four heavy-mineral provinces are distinguished in the beach sands. Beach sands from the northwestern Marmara Sea are characterized by a scarcity of the heavy minerals, which are represented mainly by mica and chlorite. They are derived from erosion of the soft and friable Miocene sandstones exposed in the region. In the north-central Marmara Sea, the beach sands have a relatively high proportion of heavy minerals, which are dominated by opaques, epidote, and garnet. The heavy-mineral composition of these beach sands reflects those of the Oligocene sandstones in the hinterland. Beach sands in the eastern Marmara Sea are varied in their heavy-mineral composition, reflecting a heterogeneous hinterland. Beach sands in the southern Marmara Sea are characterized by a high proportion of heavy minerals dominated by amphibole+pyroxene, epidote, and opaque. Heavy minerals in the sandy layers in the gravity cores differ from those of the beach sands by a decrease in the concentration of high-density heavy minerals, and increase in mica and chlorite, related to transport processes. Nevertheless, comparison of the heavy-mineral assemblages and heavy-mineral ratios between the beach sands, and sands from the deep basins suggests a sediment transport from the west from the Miocene sandstones for the Western (Tekirdağ) basin. For the Central basin, sandy layers from a single gravity core show variable heavy-mineral assemblages, suggesting derivation from both north and south of the Marmara Sea. The Eastern (Çınarcık) basin receives at least some of its sandy sediment from the east through the Bay of Izmit.

Earthquake hazard in Marmara Region, Turkey

Earthquake hazard in the Marmara Region, Turkey has been investigated using time-independent probabilistic (simple Poissonian) and time-dependent probabilistic (renewal) models. The study culminated in hazard maps of the Marmara Region depicting peak ground acceleration (PGA) and spectral accelerations (SA)'s at 0.2 and 1 s periods corresponding to 10 and 2% probabilities of exceedance in 50 yrs. The historical seismicity, the tectonic models and the known slip rates along the faults constitute the main data used in the assignment. Based on recent findings it has been possible to provide a fault segmentation model for the Marmara Sea. For the main Marmara Fault this model essentially identifies fault segments for different structural, tectonic and geometrical features and historical earthquake occurrences. The damage distribution and pattern of the historical earthquakes have been carefully correlated with this fault segmentation model. The inter-event time period between characteristic earthquakes in these segments is consistently estimated by dividing the seismic slip estimated from the earthquake catalog by the GPS-derived slip rate of 22±3 mm/yr. The remaining segments in the eastern and southern Marmara region are also identified using recent geological, geophysical studies and historical earthquakes. The model assumes that seismic energy along the segments is released by characteristic earthquakes. For the probabilistic studies characteristic earthquake based recurrence relationships are used. Assuming normal distribution of inter-arrival times of characteristic earthquakes, the ‘mean recurrence time’, ‘covariance’ and the ‘time since last earthquake’ are developed for each segment. For the renewal model, the conditional probability for each fault segment is calculated from the mean recurrence interval of the characteristic earthquake, the elapsed time since the last major earthquake and the exposure period. The probabilities are conditional since they change as a function of the time elapsed since the last earthquake. For the background earthquake activity, a spatially smoothed seismicity is determined for each cell of a grid composed of cells of size 0.005°×0.005°. The ground motions are determined for soft rock (NEHRP B/C boundary) conditions. Western US-based attenuation relationships are utilized, since they show a good correlation with the attenuation characteristics of ground motion in the Marmara region. The possibility, that an event ruptures several fault segments (i.e. cascading), is also taken into account and investigated by two possible models of cascading. Differences between Poissonian and renewal models, and also the effect of cascading have been discussed with the help of PGA ratio maps.

Late Holocene erosion in NW Anatolia from sediments of Lake Manyas, Lake Ulubat and the southern shelf of the Marmara Sea, Turkey

This paper deals with modern and ancient sedimentation in fresh water lakes and the marine shelf of the southern Marmara region, NW Anatolia, Turkey. Most of the information has been obtained from monitoring of suspended load discharged into two lakes (Manyas and Ulubat) in the last 45 years and from 8 to 11 m thick lacustrine sediments, in addition to radiocarbon-dated shelf sediments. This allows a holistic approach to the drainage basin denudation over time. The results show that the sedimentation rates in the lakes were low 0.22 cm year −1, from 4000 to 2000 years BP and then they increased (0.29 cm year −1) up to sub-recent times and reached 0.44 cm year −1 in the last century. It is suggested that deforestation created high rates of sedimentation in the basins and/or strong denudation of the region during the Late Holocene. This study also shows that for shallow freshwater lakes the calculation of sedimentation rates must include fine particles lost by the outlets and coarse-grained bed load deposited on their shores. In addition, a high rate of sedimentation has been created by short, but repetitive intense depositions. During the last century particularly during the last 45 years, the rate of sedimentation or denudation has increased dramatically in NW Turkey. The two World Wars and mismanagement of the land had important local effects by increasing deforestation and resulting in the present erosive conditions.

On the status and distribution of the Striped Hyaena, Hyaena hyaena, in Turkey

A review of literature records, many of them from the 19th and early 20th centuries, shows that the Striped Hyaena, Hyaena hyaena, has apparently always been rare in Turkey. The natural distribution area extends from the southern Marmara region (Lake İznik, Uludağ) over the Dardanelles and along the Aegean and Mediterranean coast to south-east Anatolia. Historical records from inner and eastern Anatolia are not considered as reliable, and the Turkish population has apparently never had a direct link with the populations living in the Caucasus. Recent field surveys show that the species still survives in Turkey, even in some western parts. Over the last 25 years, records are only available from a few areas; they come from the regions of Çan (Çanakkale province), Bergama (Kozak Yaylası and Yuntdağ area), Bafa Gölü/Milas, Antalya (Termessos National Park), Bolkar Mountains, Amanos mountains (Hatay province), and south-east Anatolia. The most spectacular record is from Altınözü in the Amanos mountains, where a local hunter trapped four individuals between 2002 and 2004, which were kept for some time in captivity before they were released again into the wild. The species is now highly threatened in Turkey and is on the verge of extinction, although our recent field work shows that still undiscovered populations may exist and that the total population, albeit fragmented, may be higher than hitherto thought. The paper includes the description of habitats and of museum specimens.