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Cultivation, overgrazing, and overharvesting are seriously degrading forest and grassland ecosystems in the Taurus Mountains of the southern Mediterranean region of Turkey. This study investigated the effects of changes on soil organic carbon (SOC) content and other physical soil properties over a 12-year period in three adjacent ecosystems in a Mediterranean plateau. The ecosystems were cropland (converted from grasslands in 1990), open forest, and grassland. Soil samples from two depths, 0–10 and 10–20 cm, were collected for chemical and physical analyses at each of cropland, open forest, and grassland ecosystems. SOC pools at the 0–20 cm depth of cropland, forest, and grassland ecosystems were estimated at 32,636, 56,480, and 57,317 kg ha−1, respectively. Conversion of grassland into cropland during the 12-year period increased the bulk density by 10.5% and soil erodibility by 46.2%; it decreased SOM by 48.8%, SOC content by 43%, available water capacity (AWC) by 30.5%, and total porosity by 9.1% for the 0–20 cm soil depth (p<0.001). The correlation matrix revealed that SOC content was positively correlated with AWC, total porosity, mean weight diameter (MWD), forest, and grassland, and negatively with bulk density, pH, soil erodibility factor, and cropland. The multiple regression (MLR) models indicated that any two of the three ecosystems and one of the two soil depths accounted for 86.5% of variation in mean SOC values ((p<0.001). 相似文献
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Education infrastructure issues have been one of the most important topics in developing countries that have difficulty reserving money for education infrastructure needs, especially Turkey. Development plans have a crucial role in meeting school infrastructure needs in Turkey. Generally, the expropriation method has been used for land transitions from private to public ownership. However, scarcity of monetary resources for such land transitions and legal/technical deficiencies delays the process. The main objectives of this paper are to respond to the need of the education sector by using land management tools and to identify the most suitable land management tool for allocating basic and primary school lands free of charge. Current trends, education indicators, management responsibility and financial resources, statistical and economical information, education infrastructure needs, and qualitative-quantitative characteristics of the pupils in the Turkish education system are analyzed based on national and international reports. Then, the property right problems experienced in the process of allocating school lands are defined. Methods of transferring school lands to public ownership are examined, and the benefit-cost relationships are revealed. Land readjustment (LR) would make an important contribution to planning decisions and the implementation stage in the sustainable management of school lands. 相似文献
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A. Smith R. W. Atkins S. Bradbury O. Celik Y. C. K. Chow P. Cogan C. Dowdall S. J. Fegan P. Fortin D. Gall G. H. Gillanders J. Grube K. J. Gutierrez T. A. Hall D. Hanna J. Holder D. Horan S. B. Hughes T. B. Humensky I. Jung P. Kaaret G. Kenny M. Kertzman D. B. Kieda A. Konopelko H. Krawczynski F. Krennrich M. J. Lang S. Le Bohec G. Maier J. Millis P. Moriarty R. A. Ong J. S. Perkins K. Ragan G. H. Sembroski J. A. Toner L. Valcarcel V. V. Vassiliev R. G. Wagner S. P. Wakely T. C. Weekes R. J. White D. A. Williams 《Astrophysics and Space Science》2007,309(1-4):299-303
In this paper we present the results of the past two years observations on the galactic microquasar LS I +61 303 with the
Whipple 10 m gamma-ray telescope. The recent MAGIC detection of the source between 200 GeV and 4 TeV suggests that the source
is periodic with very high energy (VHE) gamma-ray emission linked to its orbital cycle. The entire 50-hour data set obtained
with Whipple from 2004 to 2006 was analyzed with no reliable detection resulting. The upper limits obtained in the 2005–2006
season covered several of the same epochs as the MAGIC Telescope detections, albeit with lower sensitivity. Upper limits are
placed on emission during the orbital phases of 0→0.1 and 0.8→1, phases which are not included in the MAGIC data set.
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The effect of a reactive azo dye (the hydrolyzed form of Reactive Orange 107, HRO107) on the digestion of municipal waste sludge (WS) was studied. The study also focused on the effect of acclimation of the anaerobic mixed culture on dye treatment. Anaerobic batch assays were carried out in serum bottles under mesophilic conditions. Unacclimated and acclimated anaerobic mixed cultures were used for the study. Both unacclimated and acclimated anaerobic cultures completely reduced HRO107 during WS digestion. Inhibitory HRO107 concentration was found to be 800 mg/L for unacclimated mixed culture. Acclimation increased the inhibitory concentration level from 800 to 3200 mg/L. Sulfanilic acid and four other unidentified dye reduction end products were detected at the end of the assays. The results of this study indicated that anaerobic municipal WS digesters have the potential to be a cost efficient and effective pre treatment method. 相似文献
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H. S. B. Duzgun M. S. Yucemen H. S. Kalaycioglu K. Celik S. Kemec K. Ertugay A. Deniz 《Natural Hazards》2011,59(2):917-947
In this paper, an integrated urban earthquake vulnerability assessment framework, which considers vulnerability of urban environment
in a holistic manner and performs the vulnerability assessment for the neighborhood scale, is proposed. The main motivation
behind this approach is the inability to implement existing vulnerability assessment methodologies for countries like Turkey,
where the required data are usually missing or inadequate for the decision-makers in prioritization their limited resources
for risk reduction in the administrative units from which they are responsible for. The methodology integrates socio-economical,
structural, coastal, ground condition, vulnerabilities (fragilities), as well as accessibility to critical services. The proposed
methodology is implemented for Eskisehir, which is one of the metropolitans of Turkey. In the implementation of the proposed
framework, geographic information system (GIS) is used. While the overall vulnerabilities obtained for neighborhoods are mapped
in GIS, the overall vulnerabilities obtained for buildings are visualized in 3D city model. The main reason behind using different
mapping and visualization tools for vulnerabilities is to provide better ways for communicating with decision-makers. The
implementation of the proposed vulnerability assessment methodology indicates that an urban area may have different vulnerability
patterns in terms of structural, socio-economical, and accessibility to critical services. When such patterns are investigated,
effective vulnerability reduction policies can be designed by the decision-makers. The proposed methodology well serves for
this purpose. 相似文献
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Adaptive neuro-fuzzy inference system (ANFIS) and artificial neural network (ANN) models have been extensively used to predict
different soil properties in geotechnical applications. In this study, it was aimed to develop ANFIS and ANN models to predict
the unconfined compressive strength (UCS) of compacted soils. For this purpose, 84 soil samples with different grain-size
distribution compacted at optimum water content were subjected to the unconfined compressive tests to determine their UCS
values. Many of the test results (for 64 samples) were used to train the ANFIS and the ANN models, and the rest of the experimental
results (for 20 samples) were used to predict the UCS of compacted samples. To train these models, the clay content, fine
silt content, coarse silt content, fine sand content, middle sand content, coarse sand content, and gravel content of the
total soil mass were used as input data for these models. The UCS values of compacted soils were output data in these models.
The ANFIS model results were compared with those of the ANN model and it was seen that the ANFIS model results were very encouraging.
Consequently, the results of this study have important findings indicating reliable and simple prediction tools for the UCS
of compacted soils. 相似文献
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Nurgul Celik Balci 《Environmental Earth Sciences》2010,60(3):485-493
A series of experiments was conducted to better understand the bacterial influence on the release of trace metals during oxidation
of sphalerite mineral and element cycles in acid mine drainage (AMD) systems. Batch experiments were carried out as biotic
and abiotic control at pH 3. Acidithiobacillus ferrooxidans, sulfur and Fe(II) oxidizer, was used in the biotic sphalerite experiment. The abiotic control experiment was run without
adding the bacteria. The release behavior of six trace metals (As, Cd, Co, Pb, Cu and Mn), Fe and Zn were determined during
the period of 54 days. Compared to the abiotic experiments, enhanced oxidation of sphalerite by bacteria produced high sulfate
(~2,000 mg/L) and Fetot (139 mg/L) along with the low pH (<2.3). Consistent with this, the concentration of trace metals (As, Cd, Co, Pb, Cu and
Mn) was significantly higher in the biotic experiments than those in the abiotic experiments. Results indicate that the distributions
of Co and Cd in both biotic and abiotic experiments are directly related to the sphalerite dissolution whereas Pb, Cu distribution
shows no strong relation to sphalerite dissolution especially in the abiotic experiments. Pb distribution in the solution
appears to be controlled by pH-dependent solubility. Approximately 80% of the trace metals were removed from the solution
at the end of the biotic experiments along with biologically induced Fe precipitation. Experimental results showed that bacteria
play major role not only in the release of trace metal from sphalerite but also in controlling concentration of the metals
in the solution by producing Fe-oxyhydroxides. The study suggest that in order to develop an effective rehabilitation strategy
for AMD, it is necessary to understand bio/geochemical processes governing mobilization and deposition of trace metals in
the environment. 相似文献
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E. Celik M. Erdogan A. T. Gumus 《International Journal of Environmental Science and Technology》2016,13(5):1377-1392
In this paper, first, the criteria that make logistics service providers more “green” are determined as: cooperation with customer’s company and its customer, green government regulations, environmental management system, green process design, reduction in energy consumption and green network design. The criteria weights are determined by fuzzy AHP, based on expert opinions. Then, a new method is proposed, which is the combination of fuzzy TOPSIS and GRA, and used to evaluate green 3PLs based on different separation measures, as an extension, using trapezoidal fuzzy numbers. Five Turkish 3PLs serve in Istanbul are selected in order to apply a case study to show the applicability of the proposed method. Finally, the proposed method is verified with respect to different resolving coefficient values and separation measures and also compared with fuzzy TOPSIS and fuzzy VIKOR method results. Different multi-criteria decision-making methods can be applied and compared to check validity of our results for future studies. The proposed method can also be implemented to 3PLs in other countries. 相似文献