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21.
Assessment of surface water quality using multivariate statistical techniques: a case study of Behrimaz Stream, Turkey 总被引:3,自引:0,他引:3
Multivariate statistical techniques, such as cluster analysis (CA), principal component analysis, and factor analysis, were applied for the evaluation of temporal/spatial variations and for the interpretation of a water quality data set of the Behrimaz Stream, obtained during 1 year of monitoring of 20 parameters at four different sites. Hierarchical CA grouped 12 months into two periods (the first and second periods) and classified four monitoring sites into two groups (group A and group B), i.e., relatively less polluted (LP) and medium polluted (MP) sites, based on similarities of water quality characteristics. Factor analysis/principal component analysis, applied to the data sets of the two different groups obtained from cluster analysis, resulted in five latent factors amounting to 88.32% and 88.93% of the total variance in water quality data sets of LP and MP areas, respectively. Varifactors obtained from factor analysis indicate that the parameters responsible for water quality variations are mainly related to discharge, temperature, and soluble minerals (natural) and nutrients (nonpoint sources: agricultural activities) in relatively less polluted areas; and organic pollution (point source: domestic wastewater) and nutrients (nonpoint sources: agricultural activities and surface runoff from villages) in medium polluted areas in the basin. Thus, this study illustrates the utility of multivariate statistical techniques for analysis and interpretation of data sets and, in water quality assessment, identification of pollution sources/factors and understanding temporal/spatial variations in water quality for effective stream water quality management. 相似文献
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Classically distribution coefficient is defined as the ratio of solid total element concentration to surface water total concentration. This coefficient is obtained from the ion measurements in the Keban Dam, Turkey, which supplies water for domestic, irrigation and hydroelectric energy generation purposes. The measurements of 137Cs are carried out in 40 different sites and the general risk formulation and application is achieved for the distribution coefficient. The models are of exponential type and the spatial independence of the data is considered. Various charts are prepared for a set of risk levels as 5%, 10%, 20%, 25%, and 50%. 相似文献
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Combining AHP with GIS for landfill site selection: A case study in the Lake Beyşehir catchment area (Konya,Turkey) 总被引:1,自引:0,他引:1
Şehnaz Şener Erhan Şener Bilgehan Nas Remzi Karagüzel 《Waste management (New York, N.Y.)》2010,30(11):2037-2046
Landfills are the most common method for the disposal of municipal solid waste (MSW) in Turkey. However, determining the location of landfill sites is a difficult and complex process because it must combine social, environmental and technical parameters. Additionally, it depends on several criteria and regulations. The main objective of this study was to select of a landfill site for the Lake Bey?ehir catchment area. The Bey?ehir Lake is the largest freshwater lake and drinking water reservoir in Turkey, but there is no controlled landfill site in the region. Therefore, the landfill site should be determined such that the lake is protected. To determine the most suitable landfill site, an analytical hierarchy process (AHP) was combined with a geographic information system (GIS) to examine several criteria, such as geology/hydrogeology, land use, slope, height, aspect and distance from settlements, surface waters, roads, and protected areas (ecologic, scientific or historic). Each criterion was evaluated with the aid of AHP and mapped by GIS. Data were assorted into four suitability classes within the study area, i.e., high, moderate, low and very low suitability areas, which represented 3.24%, 7.55%, 12.70% and 2.81%, of the study area, respectively. Additionally, 73.70% was determined to be completely unsuitable for a landfill site. As a result, two candidate landfill sites are suggested and discussed. The final decision for landfill site selection will require more detailed field studies. 相似文献
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Kandemir Aysun Şahin Bayram 《International journal of occupational safety and ergonomics》2013,19(4):501-509
Objective. This study aimed to determine the associations between sickness presenteeism and socio-demographic factors, perceived health status and health complaints among hospital staff and to calculate the cost burdens and productivity losses attributed to presenteeism. Methods. A cross-sectional study was conducted using 951 hospital staff, including physicians, nurses, midwives, other health personnel and administrative staff working in two hospitals located in K?r?kkale province in Turkey. The health and work performance questionnaire developed by Kessler et al. was revised to measure sickness presenteeism. Results. After performing Student’s t test and a one-way analysis of variance, presenteeism was mostly observed in women, nurse-midwives, young employees, university health staff and health workers with low health status. Average productivity loss and cost of lost productivity per staff member were calculated as 19.92?h/TRY 315.57 for 2 weeks and 478.08?h/TRY 7573.68 for 1 year. Conclusions. The problem of sickness presenteeism is mostly observed in women and nurses. It causes both financial burdens and productivity losses for hospitals. These survey results are thus expected to provide critically important information on presenteeism for decision-makers and healthcare managers. 相似文献
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Şeker Mehmet Emin Erdoğan Ayşegül Korkmaz Seda Dicle Küplülü Özlem 《Environmental science and pollution research international》2022,29(24):36161-36169
Environmental Science and Pollution Research - In this study, pollens were collected from 25 different locations of Northern Turkey to investigate pollution monitoring. Surface chemistry of pollen... 相似文献
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The Effects of Long-Term Grazing Exclosures on Range Plants in the Central Anatolian Region of Turkey 总被引:1,自引:0,他引:1
Over the last fifty years, almost half of the steppe rangeland in the Central Anatolian Region of Turkey (CAR) has been converted
to cropland without an equivalent reduction in grazing animals. This shift has led to heavy grazing pressure on rangeland
vegetation. A study was initiated in June 2003 using 6 multiscale Modified-Whittaker plots to determine differences in plant
composition between areas that have not been grazed in 27 years with neighboring grazed plant communities. A total of 113
plant species were identified in the study area with the ungrazed plots containing 32 plants more than the grazed plots. The
major species were Astragalus acicularis, Bromus tomentellus, Festuca valesiaca, Genista albida, Globularia orientalis, Poa bulbosa, and Thymus spyleus ssp rosulans. Grazing impacts on forbs were more pronounced than for grasses and shrubs. Based on Jaccard’s index, there was only a 37%
similarity of plant species between the two treatments. Our study led to four generalizations about the current grazing regime
and long-term exclosures in the steppe rangeland around the study area: (1) exclosures will increase species richness, (2)
heavy grazing may have removed some plant species, (3) complete protection from grazing for a prolonged period of time after
a long history of grazing disturbance may not lead to an increase in desirable plant species with a concomitant improvement
in range condition, and (4) research needs to be conducted to determine how these rangelands can be improved. 相似文献
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The effects of exposure of tilapia (Oreochromis mossambicus) to sublethal concentrations of lead on hematological and immunological parameters were investigated. The fish were semistatically exposed to low (L) (0.5 mg L?1), medium (M) (2.5 mg L?1), and high (H) (5 mg L?1) lead concentrations for 14 days. At the end of the trial, red blood cell (RBC) count, hematocrit (Hct) ratio and hemoglobin levels showed significant decreases in M and H groups, while RBC was significantly increased in L group compared to control group. Lysozyme activity showed a decrease in all groups on day 14 compared to control. A decrease in myeloperoxidase activity was seen in M and H groups on day 7, and in all treatment groups on day 14. In conclusion, it was found that exposure of O. mossambicus to lead concentrations affected hematological and immunogical parameters adversely. 相似文献
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Hepcan S 《Environmental management》2000,26(3):329-338
/ This study was undertaken to (1) determine the suitability of ecosystems within Mount Spil National Park (Turkey) to human activities by a systematic zoning procedure, and (2) provide the basis for developing sound management strategies based on natural-cultural resource attributes of the park. After assessing natural-cultural resources and human activity requirements, the suitability of three zones (Strict Protection Zone, SPZ; Restricted Use Zone, RUZ; and Recreation and Administration Zone, RAZ) for proposed human activities/land uses was determined in order to maintain ecological sustainability and integrity through a weighting-ranking methodology, based on a grid cell resolution of 1 km x 1 km. Results showed that out of the three management zones, the RUZ in which the recreational activities that do not require physical developments are allowed constituted 82% of the park area as the first priority management zone. The proposed zoning procedure is believed to be a key step to improve management for both the study area and other national parks with the similar landscape features. 相似文献