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121.
Melek Er Osman Tugay Mehmet Musa Özcan Deniz Ulukuş Fahad AL-Juhaimi 《Environmental monitoring and assessment》2013,185(6):5193-5198
Antioxidant capacity, total phenol and mineral contents of aerial parts of sage belonging to some Salvia species were established. The lowest and highest antioxidant values of Salvia dichroantha Stapf and Salvia heldreichiana Boiss. ex Benth. extracts were found as 73.855 and 80.207 mg GAE/g, respectively. While the highest total phenol was established in Salvia tomentosa Mil. (13.316 mg GAE/100 ml), the lowest level was found in Salvia halophila Hedge (6.168 mg GAE/100 ml). While K contents of plants changed between 14,518 and 24,171 mg/kg, Ca contents ranged between 12,402 and 18,553 mg/kg. P and Mg contents were found low compared with K and P values of plants. Mg content was changed between 2,118 and 2,914 mg/kg; the mean was calculated as 2,496 mg/kg. P contents of plants were determined between 1,385 to 1,910 mg/kg. As a microelement, Fe was found at the highest level. Fe contents of plants were found between 179 and 782 mg/kg. 相似文献
122.
Gökben Başaran Kankılıç İlhami Tüzün Yusuf Kağan Kadıoğlu 《Environmental monitoring and assessment》2013,185(8):6739-6750
In this study, the concentrations of 13 elements (Al, Fe, Mn, Cr, Ni, Zn, Co, As, Pb, Cu, Mo, Hg, and Cd) were determined in the sediments of three different sites in the Kapulukaya Dam Lake between May 2007 and November 2008. They ranged from 1.47 to 4.64 for Al, 0.92 to 3.48 for Fe (in percent), 326.60 to 1053.00 for Mn, 98.00 to 1,116.00 for Cr, 24.70 to 127.10 for Ni, 14.80 to 124.20 for Zn, 11.0 to 43.20 for Co, 5.00 to 29.30 for Cu, 9.10 to 69.70 for As, 8.60 to 34.00 for Pb, 2.50 to 5.20 for Mo, 1.00 to 1.60 for Hg, and 0.50 to1.80 for Cd in microgram per gram dry weight sediment. The contamination degree of the sediment was assessed on the basis of enrichment factor and corresponding sediment quality guideline. The calculated enrichment factors (EF, measured metal vs. background concentrations) indicated that the effect of man-made activities on the occurrence of concentrations could be accounted for the majority of heavy metals namely Mn, As, Ni, Cu, Zn, Cr, Co, Mo, and Cd, whereas such affect was not detected for Hg and Pb. The maximum values of the EF were represented by As, minimum values by Hg at all sites. Mean EF values were 36.60 and 0.70 for As and Hg, respectively. This study has clearly assessed a certain level of heavy metal pollution in the region, based particularly on the findings from sediment. 相似文献
123.
124.
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
125.
Recognition and understanding of landscape dynamics as a historical legacy of disturbances are necessary for sustainable management
of forest ecosystems. This study analyzed spatial and temporal changes in land use and land cover patterns in a typical mountain
watershed in the Gumushane district along the Northeastern part of Turkey. The area is investigated by comparing LANDSAT images
from 1987 to 2000 and evaluated the temporal changes of spatial structure of forest conditions through spatial analysis of
forest cover type maps from 1971 and 1987 using GIS and FRAGSTATS™.
The results show a general decreasing trend in area of natural land cover types including broadleaf and conifer forests as
well as coppice between 1971 and 1987 (0.54%, respectively). In contrast, between 1987 and 2000 this natural land cover types
show increasing trend (1.6%). In parallel with forest dynamics, the area of managed land including lowland and upland agricultural
areas, rangelands and grasslands increased during the first period and decreased during second period. In terms of spatial
configuration, Gümüşhane forests aren’t generally fragmented by intensive forest utilization in the latter periods. This is
partially due to out-migration of rural population in Gümüşhane. Nevertheless, land use pattern significantly changed over
time depending on a few factors such as unregulated management actions, social pressure and demographic movements. The study
revealed that demographic movements have a major effect on landscape dynamics. 相似文献
126.
Accumulation of Tobacco mosaic virus (TMV) at different depths clay and loamy sand textural soils due to tobacco waste application 总被引:3,自引:0,他引:3
The effects of tobacco waste (TW) application to the soil surface on the accumulation of Tobacco mosaic virus (TMV) in clay and loamy sand textural soils at various depths were investigated in two different fields. The tobacco waste had been found to be infected with TMV. Eighteen months after TW application to the soil surface, soils were sampled at 20 cm intervals through to 80 cm depth. The DAS-ELISA method was performed to determine infection of soil with TMV. The viruses persisted in clay soil for a long period compared with loamy sand soil. There was no accumulation of TMV at any depth of loamy sand soil in Experimental Field 2. TMV adsorption to soil particles in 0-60 cm depth of clay soil was determined in all TW treatments in Experimental Field 1. The highest ELISA Absorbance (A405) values in all treatments were determined in the 20-40 cm soil depth that had the highest clay content. ELISA A405 values of TMV at different depths of clay soil gave significant correlations with clay content (r = 0.793**), EC values (r = 0.421**) and soil pH (r = -0.405**). Adsorption of TMV to net negatively charged clay particle surfaces increased with increasing EC values of soil solution. Decreasing soil pH and infiltration rate increased adsorption of TMV to clay particles. Higher infiltration rate and lower clay content in loamy sand soil caused leaching of TMV from the soil profile. 相似文献
127.
This study aimed at quantifying noise pollution from urban traffic in the city of Kahramanmara?, Turkey. A total of 114 measurements for the equivalent noise level (L Aeq) were made at 38 urban locations classified as “residential areas”, “residential and commercial areas” and “industrial areas” according to the national regulations, during morning, mid-day and evening hours. Our findings tabulated and mapped revealed that mean noise level in “residential and commercial areas” was highest relative to the other land-use types. Minimum and maximum values of noise pollution were recorded during the mid-day and evening hours, regardless of the land-use types. Noise limit values were exceeded at two locations only out of 38 based on the national regulation criteria and at over half of the locations based on the international criteria. 相似文献
128.
Heavy metals in water and in tissues of himri (Carasobarbus luteus) from Orontes (Asi) River, Turkey
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?0.05) in the concentration of the studied metals in the selected tissues, except gonads (p?>?0.05), which showed seasonal variation of only Zn (p?0.05). Maximum concentrations of Ag, Cd, Cr and Pb were detected in gonads followed by liver, gill, skin and muscle while maximum concentrations of Cu, Fe, Ni and Zn were detected in liver followed by other tissues. Concentrations of heavy metals in the muscle of 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
129.
130.
Physical and chemical parameters have been analyzed in water samples from a brackish water lagoon, Küçükçekmece, located on the western outskirts of Istanbul. Samples were collected every two months for a year from nine sampling stations. Of the parameters measured, temperature, pH, salinity, nitrate and phosphate showed changes when compared with the previously published data. The lagoon was found eutrophic as it was reported previously. Sulphate and COD levels were higher when compared with the standards established by the Turkish Water Pollution and Control Regulation. Additionally, concentrations of heavy metals (Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn) in water and bottom sediments were measured and compared with the standards established by the Turkish Water Pollution and Control Regulation and with the previously published data. The results were analysed statistically with respect to location and any relationships between the concentration of the elements in corresponding water and sediment samples were examined. Principal Component Analysis of water samples allowed us to discriminate three areas affected mainly by heavy metal contamination, possibly due to industrial, commercial and/or urban activities. Generally, the concentrations of the heavy metals were higher at stations near the three estuaries, suggesting a direct influence of the three creeks on the pollution of the Küçükçekmece Lagoon. Although elevated levels of Cd were recorded in several water samples, it was not detected in sediment. On the other hand, a particularly high level of Cr pollution was recorded most of the water and sediment samples. 相似文献