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71.
Environmental Science and Pollution Research - This study estimated unbalanced panel data analysis to investigate the relationship among CO2 emissions, GDP, renewable and non-renewable energy...  相似文献   
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The surface water quality of the Euphrates river basin in Turkey are evaluated by using the multivariate statistical techniques known as factor analysis (FA) and multidimensional scaling (MDS) analysis. When FA was applied to the water quality data obtained from the 15 different surface water quality monitoring stations, two factors were identified, which were responsible from the 86.02% of the total variance of the water quality in the Euphrates river basin. The first factor called the urban land use factor explained 44.20% of the total variance and the second factor called the agricultural use factor explained 41.81% of the total variance. MDS technique showed that electrical conductivity (EC), percent sodium (Na%) and total salt are the most important variables causing difference in the water quality analysis.  相似文献   
75.
Total mercury concentrations in organisms typical of those found in the Cilician Basin of the northeastern Mediterranean have been measured from 1977 to the present. These concentrations show seasonal variations. Shrimp shows an approximately constant concentration of mercury which might testify to the regulation capacity of shrimp for mercury. Crab, and particular fish, show a seasonal variation which may be correlated with the local application of mercury fungicide, rainfall, and the physiology of the organisms. The rapidity with which mercury applied to the land causes increased concentrations in fish is noteworthy.  相似文献   
76.
Concentrations of heavy metals (Ag, Cd, Cr, Cu, Fe, Ni, Pb ve Zn) were measured in running water and in tissues (muscle, liver, gill, skin and gonads) of one commercially valuable fish species (Carasobarbus luteus) from the Orontes (Asi) River (Güzelburç region) in Hatay (Southeastern Turkey). Results for levels in water compared with national and international water quality guidelines were found at the highest concentrations in international criteria’s WHO, EC and EPA, but Cd, Cu, Ni and Pb were found to exceed permissible level of drinking water in national criteria TSE-266 whereas Fe, Zn and Cr concentrations were within the permissible levels for drinking. The present study showed a significant seasonal variation (p?p?>?0.05), which showed seasonal variation of only Zn (p?C. luteus were below the permissible limit for human consumption, level of Cu being very close to the permissible limit. Consequently, continuous monitoring of heavy metal concentration in edible freshwater fish will be needed in Orontes River.  相似文献   
77.
Different sources of pollution in Karasu Creek were investigated to obtain the water quality and ratio of contamination in this region. To achieve the main objectives of the present study, water samples were collected from Karasu Creek, starting from flow pattern at the upstream site of Akkaya Dam to the end of the dam, crossing the place where the Creek drains into. Dissolved oxygen, electrical conductivity, temperature and maximum/minimum pH were measured systematically for 12 months in the stations, where the water samples were collected. Chemical analyses of the water samples were carried out by using Cadas 50 S brand UV spectrometer to find out the Pb, Fe, Cu, Zn, Ni, Cr, Cd, S, F and Cn concentrations. These concentration were determined in μg/lt as 80–850; 180–4,920; 10–6,100; 440–25,530; 130–2,400; 120–280; 20–150; 214,250–1,113,580; 1,560–4,270 and 40–690, respectively. To determine metal levels of the water samples, multivariate analyses (element coefficient correlation, coefficient correlation dendrogram, hierarchical cluster analysis dendrogram, model summary and ANOVA) were used. The analyses yielded highly accurate results. There were positive correlations between some elements and their possible sources were the same. The stations which resembled each other along the creek were divided into three groups. The water quality of the creek was low and had toxic qualities. Eutrophication developed in Akkaya Dam along the creek. The source of pollution was thought to be industrial and residential wastes. Absolute (0–100 m), short distance (100–500 m) and medium distance (500–2,000 m) conservation areas should be determined in pollution areas along Karasu Creek and they should be improved.  相似文献   
78.
Rapid economic growth, increasing population and change in living standards contribute to increasing the generation rate of municipal solid waste (MSW) in Denizli city, like other Turkish cities. The improper and poor MSW management system (old system) in Denizli caused environmental problems originating from the uncontrolled release of methane and leachate. In addition, the disposal of recyclable materials in unsanitary landfills is responsible for the consumption and destruction of natural sources. This paper presents a general overview of old and new MSW management practices in Denizli. Detailed data on MSW management practices including collection, transportation, disposal and recycling have been presented. The amount of solid waste generated in Denizli over the last decade has increased steadily over the years, from 108,500 tons in 1995 to 179,495 tons in 2006. The average MSW generation rate was found to be 1.23kg/day per capita. The major constituent of MSW in Denizli is food waste, but the percentage of recyclable waste has increased significantly recently. Except for metal wastes, the percentages of recyclable waste materials in Denizli are higher than in all neighborhood cities. The objective of this study is to compare the old and new MSW management systems in Denizli city. The MSW management system has been changed entirely last five years. A dumpsite was closed and a sanitary landfill with a composting facility was constructed. In addition, source separated collection has been carried out since 2002. The quantity of recyclable waste collected increased from 195 to 1549 tons. The amount of recyclable waste will continue to be increased by expanding the source separation collection system to all the districts of the city and preventing scavenging. Thus, revenue from recyclable waste ($7227 in 2006) is expected to increase. In addition, the capacity of the composting facility will be increased. Most importantly, information to increase public participation and awareness in municipal recovery programs has to be provided.  相似文献   
79.
Today, the removal of increased amount of contaminant concentrations in nature such as metals, nanoparticles, has become an essential issue to struggle with. In this paper, both the toxic effects of non-essential Cd on Lemna minor in presence of alginate microspheres and metal removal capacity of Cd-exposed L. minor and microspheres were investigated. Three test groups were constructed: group (L) containing Lemna, group (M) containing alginate microsphere and group (L?+?M) containing alginate microsphere and Lemna. Five different levels of Cd concentrations were added into these groups. Estimation models were constructed to estimate Cd removal capacities of L. minor and microspheres, and time-concentration-dependent growth (GRC) rates of both microsphere-containing and non-containing groups were modelled by regression analysis. It was seen that microspheres alone only had no positive or negative effects on Lemna growth. It was observed that, for all test groups the time-dependent growth rate has both increase–decrease trends in general. The toxicity effect of Cd on Lemna growth was reduced by adding microspheres into medium. Furthermore, the results stated that test groups containing only microspheres (M, 0–97.56%) and consortium groups (M?+?L, 0–98.26%) were slightly more successful in Cd removal process compared to Lemna (L) groups (L, 0–97.32%).  相似文献   
80.
This study investigates the empirical relationship between energy consumption, international trade, and real income in Canada which has an important role in global energy and trade. It employs bound tests to level relationships and conditional error correction models through ARDL specification to a new version of the Solow Growth model. Using annual data of the 1960–2010 period, results reveal a long-term relationship between energy consumption, international trade, and real income in Canada. It is also found that energy exporting activity is the determinant (driver) of energy consumption through the channel of real income and energy consumption is the determinant (driver) of exports through the channel of real income in the long term of the Canadian economy. Exports and energy use are the determinants (drivers) of real income in the long term of the Canadian economy; therefore, as conditional Granger causality tests suggest there is feedback relationship between energy consumption, international trade, and real income in the long term of the Canadian economy. The present study suggests that any energy conservation policies are likely to have negative influence on output and international trade in Canada.  相似文献   
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