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Guler M.,Middle Black Sea Development Agency | Arslan H.,Ondokuz Mayis University | Cemek B.,Ondokuz Mayis University | Ersahin S.,Çankiri Karatekin University
Agricultural Water Management | Year: 2014

Soil salinity and sodicity obscure growth of many field and horticultural crops. Spatial and temporal variations of these attributes should be known to avoid their impacts on plant growth. We studied long-term changes in spatial variation in soil electrical conductivity (EC) and soil exchangeable sodium percentage (ESP) in 8186ha Bafra plain, located in Middle Black Sea region of Turkey. Data collected in 1966 and 2008 were evaluated and compared by geostatistical and GIS techniques. Semivariograms for EC and ESP were calculated and graphed for 0-30, 30-60, and 60-90cm depths for both sampling times and complementary kriging prediction maps were built. Both EC and ESP decreased from 1966 to 2008 in acreage and severity in all three studied depths. The EC values ranged from 0.32 to 22.61dSm-1 in 1966 and from 0.51 to 7.38dSm-1 in 2008, and ESP values ranged from 12.8 to 76.0 in 1966 and from 9.77 to 40.71 in 2008. In both sampling times, increasingly greater values of EC and ESP occurred by depth. In 1966, 3181ha of study area had a severe salinity and sodicity problem, while this acreage decreased to 548 for salinity and 2128ha for sodicity by 2008. Soil EC above threshold level (4dSm-1) decreased considerably from 1966 to 2008, and this decrease was attributed to that irrigation and complementary drainage removed excess salts away from the soils. Soil ESP decreased to below threshold value of 15 almost in entire area for 0-30 soil depth while it remained over threshold value in 30-60 and 60-90cm soil depths in eastern part of the study area. A multivariate analysis along with geostatistical analysis can aid to evaluate impact of soil management and land use change on soil EC/ESP as well as soil variables having correlations with EC and ESP. © 2013 Elsevier B.V.


Kilic M.,Middle Black Sea Development Agency | Kaya I.,Yildiz Technical University
Urban Studies | Year: 2016

Regional development agencies (RDA) are the units established for accelerating regional development and increasing local capacity. They aim at activating the regional dynamics and to reduce the intra-regional and inter-regional development gap. In a region, each province may have a different development level. This would pose a problem for socio-economic development. In order to reduce the disparities among the provinces, financial support mechanisms of development agencies would be a beneficial influence only if supports are used with to correct strategies. In order to play a vital role to reduce intra-regional disparities, it is necessary to consider many criteria to categorise settlements in terms of socio-economic development. Some of these criteria are generally subjective and extremely difficult to express in numbers. However, fuzzy sets are a great help to decision makers in a prioritisation of provinces for public grants allocation process with linguistic variables and measurement challenges. In this study, a new city-ranking model has been proposed for development agencies operating in Turkey. To address ambiguities and relativities in real-world scenarios more conveniently, type-2 fuzzy sets and crisp sets have been simultaneously used in multicriteria decision making (MCDM) process of grants allocation. To illustrate the proposed model better, an application with real case data has been performed in the Middle Black Sea Development Agency in Turkey. © 2015, © Urban Studies Journal Limited 2015.


Guler M.,Middle Black Sea Development Agency
Journal of the Meteorological Society of Japan | Year: 2014

Eight different interpolation methods (inverse distance weighting, spline with tension, thin-plate spline, completely regularized spline, ordinary kriging, simple kriging, universal kriging, and linear regression (LR) model) were comparatively analyzed to determine the spatial distribution of monthly reference evapotranspiration (ET0) values calculated using the Hargreaves method (ET0-HG). To compare the different methods, observation stations were divided into two data groups (58 stations for analysis and 14 stations for validation). The correlation coefficients for all months ranged between 0.68 and 0.90. Of all the methods evaluated, the LR model was found to give the optimum results. The highest correlation coefficient was observed with the LR model for all months except March, April, June, and September. UK showed lower correlation coefficients than the LR model for all months except June and September and was found to be the second-best method. Secondary data contributed positively to ET0-HG interpolation; therefore, certain spatial data was incorporated into the LR model. The relationship between the monthly ET0-HG values produced using the most efficient interpolation method, and the values calculated with the Penman-Monteith method (ET0-PM) were also investigated in this study. Correlation coefficients between the methods varied between 0.65 and 0.86 for all months. The largest difference between the two methods was observed in June (-2.27 mm day-1), and the smallest difference was seen in February (0.02 mm day-1). In conclusion, Hargreaves method was found to be easier to use in calculating ET0 for the creation of ET0 maps, in which the use of LR was found to be more reliable than other interpolation methods. © 2014, Meteorological Society of Japan.


Kilic M.,Middle Black Sea Development Agency | Kaya I.,Yildiz Technical University
Applied Soft Computing Journal | Year: 2015

Although investment projects supported by the state are extremely important in terms of national policy the projects to be transferred from the common public funds brings with it many problems. Highly transparent and comprehensive evaluation model are required to transfer the public resources to the right investment projects. It is necessary to consider many criteria for the evaluation of an investment project. These criteria are generally subjective and extremely difficult to express in numbers. However, using the fuzzy sets provide huge facilities to decision makers in project evaluation process with linguistic variables and measurement challenges. In this study, a new evaluation model for investment projects have been proposed for development agencies operating in Turkey. To address ambiguities and relativities in real world scenarios more conveniently, type-2 fuzzy sets and crisp sets have been simultaneously used. The proposed model for the investment project evaluation problem composed of type-2 fuzzy AHP and type-2 fuzzy TOPSIS methods. The proposed fuzzy MCDM method consists of three phases: (1) identify the criteria to be used in the model, (2) type-2 fuzzy AHP computations, (3) evaluation of investment projects with type-2 fuzzy TOPSIS and determination of the final rank. To perceive proposed model better, an application with real case data have been performed in Middle Black Sea Development Agency in Turkey. As a consequence of this application, it has been observed that the proposed model have proved effective in evaluation of alternatives in multi-criteria group decision making problems in a broader perspective and flexible fashion. © 2014 Elsevier B.V. All rights reserved.


Cemek B.,Ondokuz Mayis University | Guler M.,Middle Black Sea Development Agency | Arslan H.,Ondokuz Mayis University
Theoretical and Applied Climatology | Year: 2015

This study aimed to identify the most suitable growing periods for greenhouse production in Turkey in order to make valuable contribution to economic viability. Data collected from the meteorological databases of 81 provinces was used to determine periodic climatological requirements of greenhouses in terms of cooling, heating, natural ventilation, and lighting. Spatial distributions of mean daily outside temperatures and greenhouse heating requirements were derived using ordinary co-kriging (OCK) supported by Geographical Information System (GIS). Mean monthly temperatures throughout the country were found to decrease below 12 °C in January, February, March, and December, indicating heating requirements, whereas temperatures in 94.46 % of the country rose above 22 °C in July, indicating cooling requirements. Artificial lighting is not a requirement in Turkey except for November, December, and January. The Mediterranean, Aegean, Marmara, and Black Sea Regions are more advantageous than the Central, East, and Southeast Anatolia Regions in terms of greenhouse production because the Mediterranean and Aegean Regions are more advantageous in terms of heating, and the Black Sea Region is more advantageous in terms of cooling. Results of our study indicated that greenhouse cultivation of winter vegetables is possible in certain areas in the north of the country. Moreover, greenhouses could alternatively be used for drying fruits and vegetables during the summer period which requires uneconomical cooling systems due to high temperatures in the Mediterranean and Southeastern Anatolian Regions. © 2015 Springer-Verlag Wien


Arslan H.,Ondokuz Mayis University | Guler M.,Middle Black Sea Development Agency | Cemek B.,Ondokuz Mayis University
Fresenius Environmental Bulletin | Year: 2013

This study measured groundwater depths over the 2010 water year (from October 1, 2009 to September 30, 2010) and groundwater salinity in July 2010, when irrigation activities were most intense. Geostatistical methods were used to model variations in five groundwater properties (the highest groundwater depth (HGD), the lowest ground-water depth (LGD), groundwater depth in July (GDJ), groundwater elevation in July (GEJ), and groundwater salinity in July (GSJ), the month with the most intensive irrigation). Moreover, areas with drainage and salinity problems were determined with groundwater depths and salinity values using ordinary kriging and indicator kriging methods. Among the properties measured, GEJ showed minimum variability and GSJ maximum variability, whereas GSJ showed the shortest range of spatial variability and LGD the highest one. HGD and LGD were best described by a spherical semi-variogram model, whereas GSJ was best described by an exponential model. Measurements of the spatial distribution of the five groundwater properties using ordinary kriging indicated a drainage problem in 80.82% (7419 ha) of the research site, with groundwater depths ranging from 0.00-2.00 m in 35.24% (3254 ha) of the site. In addition, 16.11% of the research site was found to suffer from salinity problems (salinity levels above 5 dS m-1) and nearly 50% of the site was found to be on the verge of a salinity problem (salinity levels between 2.25-5.00 dS m-1). Indicator kriging was also applied and probability maps were generated giving the most exciting result. Areas with low groundwater elevations were determined to have more drainage problems.


High temperatures and relative humidity can induce livestock stress and a subsequent decrease in productivity, making location and time period important elements to consider when planning cattle and dairy farming investments. Turkey has a diversity of geographical features that offer the potential for breeding of all types of animals. This study used the temperature/humidity index (THI) in conjunction with a Geographical Information System (GIS) and indicator kriging to identify risky sites for cattle production in 4 provinces in northern Turkey. Findings indicated that THI values at 0700 and 2100 local time (LST; UTC+2h) fell within the normal range for all months. However, daily maximum THI values were found to vary significantly by month, exceeding the alert threshold THI value=75 at certain sites in June, July, August and September and the danger threshold THI value=79 at certain sites in July and August. THI values at 1400 LST in July and August also exceeded the alert threshold at certain sites and the danger threshold at others. Once THI values were calculated, regression analysis was performed using THI values and selected topographical features. A significant correlation (at 1%) was found between THI values and elevation for all months except April and May. The study findings suggest that cattle producers should invest in physical improvements such as shade provision and cooling fans and shift feeding times to cooler hours of the day in June, July, August and September in order to mitigate the negative effects of high temperatures and relative humidity. © 2014 Royal Meteorological Society.


Giiler M.,Middle Black Sea Development Agency | Kara T.,Ondokuz Mayis University
Fresenius Environmental Bulletin | Year: 2014

This study aimed to determine the most suitable method for modelling and mapping monthly precipitation using a geographical information system (GIS) in northern Turkey. Models were constructed using Inverse Distance Weighting (IDW), Spline, Simple Kriging, Cokriging and Linear Regression and were comparatively analyzed for effectiveness in interpolating precipitation data. Data was divided into 2 groups, with 55 stations used for analysis and 14 stations used for validation. Correlation coefficients for estimated and measured mean monthly precipitation varied between 0.69-0.98. Correlation coefficients for all months were found to be statistically significant (p<0.01). The method producing the best results varied by month, as follows: Spline: January-April, October; IDW: June, December (and annual results); Kriging: July-September, November; Linear regression: May. With the exception of linear regression, the differences between methods were statistically insignificant, indicating that IDW, Spline and Kriging (simple and cokriging) can all be used successfully in the preparation of monthly total precipitation maps in the study area. © by PSP.

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