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61.
Çevik Cem Kıdeyş Ahmet Erkan Tavşanoğlu Ülkü Nihan Kankılıç Gökben Başaran Gündoğdu Sedat 《Environmental science and pollution research international》2022,29(18):26230-26249
Environmental Science and Pollution Research - Turkey is one of the major plastic pollution sources in the Mediterranean and the Black Sea. This review summarizes present information, data, and... 相似文献
62.
Çalış Boyacı Aslı Şişman Aziz Sarıcaoğlu Köksal 《Environmental science and pollution research international》2021,28(14):17431-17444
Environmental Science and Pollution Research - The amount of municipal solid waste (MSW) has been increasing rapidly in the urban centres of developing countries during the last few decades;... 相似文献
63.
Dunes that are protected because of their very rich and diverse plant communities are often exposed to excessive visitor pressure.
The effects of trampling on the habitat must be known from a conservation viewpoint but also are important for management.
To determine the response of plant assemblages to trampling by people, an experimental study was conducted on the state-owned
dunes at Quiberon (Brittany, France). Indices of resistance and resilience were used to compare three typical plant communities
belonging to the various landscape units: mobile dune, semifixed dune, and fixed dune. The strong contrasts between communities
belonging to different successional stages reflect their ecological functioning. The mobile dune and semifixed dune with their
low resistance contrasted with the fixed dune. Only the vegetation cover of the semifixed dune benefited from long-term trampling
and had a very high resilience (134%). This response could be explained by a good balance of two opposite factors: soil compaction
increasing soil stability and moisture content, and vegetation destruction. Because of their low resilience, trampling seems
to be harmful for fixed dunes in the long term. The tourist pressure seems easier to integrate in to the mobile dunes and
the semifixed dunes if periods of recovery are included in the management. 相似文献
64.
Recep Ekiciler Muhammet Samet Ali Çetinkaya Kamil Arslan 《International Journal of Green Energy》2020,17(10):555-567
ABSTRACT Al2O3/water nanofluid has been numerically examined for the first time with different nanoparticle shapes including, cylindrical, blade, brick, platelet and spherical, on the flat and triangular-corrugated impinging surfaces. The volume fractions of 1.0%, 2.0% and 3.0% nanoparticles have been used. The Reynolds number is between 100–500 depending on the slot diameter. The finite volume method is utilized to determine the governing equations. The study is analyzed to determine how the flow features, heat transfer features and entropy production were affected by the diversity of nanoparticle shape, nanoparticle volume fraction, and shape of impinging surface. Darcy friction factor and Nusselt number are studied in detail for different conditions. The temperature contours are presented in the case of different nanoparticle volume fractions, nanoparticle shapes and both impinging surfaces. The results of the study suggest that the nanoparticle shape of the platelet shows the highest heat transfer development due to the thinner thermal boundary layer. Heat transfer augments with increasing volume fraction of nanoparticles. In addition, the study is consistent with the results of the literature on heat transfer and flow properties. 相似文献
65.
Distribution and bioaccumulation of organochlorine pesticides along the Black Sea coast 总被引:1,自引:0,他引:1
Sediment, mussel, and seawater samples were collected three times during 2001–2003 at nine sampling stations along the mid-Black
Sea coast of Turkey. The samples were analyzed with GC-ECD for contents of various organochlorine pesticides (OCPs) in the
environment. DDT and its metabolites were detected at concentrations significantly above the detection limits. The highest
concentrations of DDT metabolites measured in the sediment and mussel samples were 35.9 and 14.0 ng/g wet weight respectively.
Considerable levels of aldrin, dieldrin, endrin, heptachlor epoxide, lindane, endosulfan sulphate, and HCB were also detected
in the sediment, mussel, or seawater samples. Although these persistent toxic compounds have been banned for some years in
Turkey, they may still be used illegally in some regions, contributing to their significant levels in the environment. The
biota–sediment accumulation factor (BSAF) estimated for DDT and its metabolites in mussels was 2.9, which is nearly two times
higher than the benchmark of 1.7. In spite of such high BSAF values observed for these toxic compounds, their levels in mussels
were significantly below the international legal limits recommended by the Food and Agriculture Organization of the United
Nations. Edible biota from the waterbodies examined may thus still be considered safe for human consumption at this time.
However, as pollutants can biomagnify through the food chain over time, further routine sampling and analysis of biota along
the Black Sea coast are warranted in order to better assess the threat of OCPs to public health in the region. 相似文献
66.
Gürcan Güleryüz Ümran Seven Erdemir Hülya Arslan Ayşegül Akpinar Ayça Çiçek Şeref Güçer 《Chemistry and Ecology》2013,29(6):494-509
The aim of this study was to evaluate the effects of copper (Cu) stress on accumulation and transport of trace elements, nitrogen assimilation, and growth parameters of Verbascum olympicum. Eight-week-old seedlings were grown in Hoagland's solution and exposed to 0, 50, 250, or 500?µM CuSO4 for seven days in laboratory conditions. Bioaccumulation of trace elements (boron, bismuth, cobalt, Cu, iron, lithium, manganese, molybdenum, nickel, lead, zinc) in the roots and leaves was determined by inductively coupled plasma–mass spectrometry after one, three, and seven days. Chlorophyll content, nitrate reductase, and glutamine synthetase activities, soluble protein content, and biomass were determined. Copper accumulated in the roots and leaves (up to 19609.8 and 256.2?mg?kg?1 dry weight, respectively). Other trace elements accumulated to higher levels in the roots of Cu-treated plants compared with those of control plants. High Cu concentrations decreased nitrogen-assimilatory enzyme activities. Compared with control plants, those treated with high Cu concentrations showed lower chlorophyll contents, total protein contents, and biomass. Nitrogen assimilation and growth parameters of V. olympicum were negatively affected by Cu treatment but mineral nutrition was not severely disrupted. The results support the suitability of V. olympicum as a candidate for phytoremediation of Cu-contaminated soils. 相似文献
67.
Zinc borate is used as flame retardant for plastics and cellulose fibers, paper, rubber, and textiles. Despite its wide industrial use, there is limited information concerning its toxicity. The aim of the present study was to investigate the concentration dependence (0–280 mg L?1) of its genotoxic activity on cultured human lymphocytes by using sister chromatid exchange and chromosomal aberration assays. Total antioxidant capacity and the extent of oxidative stress were also determined. Zinc borate was found to be non-genotoxic at all tested concentrations. It exhibited antioxidant activity at concentrations lower than 40 mg L?1, and total oxidative stress levels were not changed at any applied concentration of zinc borate. 相似文献
68.
Celik K 《Environmental monitoring and assessment》2006,117(1-3):261-269
Regression and correlation analyses were used to predict responses of phytoplankton biomass (chlorophyll) (μg L−1) to nitrate (NO3) (mg L−1), phosphate (PO4) (mg L−1) and ammonium (NH4) (mg L−1) dynamics in the shallow hypertrophic Lake Manyas, Turkey. Nutrient concentrations showed a descending gradient with distance,
while chlorophyll concentrations showed an ascending gradient with the distance from the Sığırcı Inlet to the Karadere Outlet.
Higher nutrient concentrations did always not coincide with higher chlorophyll concentrations. The results showed that regression
models developed using seasonal data were more accurate in predicting chlorophyll concentrations than those developed using
the pooled data from whole year (based on R
2 and the difference between the measured and predicted values). The findings also revealed that within a single large shallow
lake, chlorophyll-nutrient relationships might show significant variations spatially. The objective of this study was to determine
the seasonal and spatial variations in the relationships between chlorophyll, nitrate, phosphate and ammonium in the shallow
hypertrophic Lake Manyas, Turkey. 相似文献
69.
The Contamination Levels of Organochlorine Pesticides in Water and Sediment Samples in Uluabat Lake, Turkey 总被引:3,自引:0,他引:3
The Uluabat Lake is a reservoir of 125 km2 surface area, in the boundaries of Bursa province, Turkey. The results showed that Uluabat Lake was still contaminated by
organochlorine pesticides and their residues despite the existence of bans over a long time. Considerable amounts of organochlorine
pesticides (HCB, p.p′-DDT, p.p′- DDE, α -, β- and γ-BHC, Aldrin, Heptachlor epoxide, Endrin, Endosulfan I and II) were detected in water and sediment samples during one-year
study in this lake. Samples of water and sediment were collected in different regions, (6 sampling point) of the lake between
February 2002 and November 2002.The mean levels of organochlorine pesticides in water and sediments were determined. According
to results, it was found that various environs in Uluabat Lake were contaminated by 11 different organochlorine pesticides.
Residue analyses showed that higher organochlorine pesticides and their residues were generally more accumulated in the sediment
samples. 相似文献
70.
Aysun Türkmen Mustafa Türkmen Yalçın Tepe Mustafa Çekiç 《Environmental monitoring and assessment》2010,168(1-4):223-230
This study was performed to investigate the metal concentrations in muscle, liver, gonad, and gill of gilthead seabream (Sparus aurata L., 1758), European seabass (Dicentrarchus labrax L., 1758), and keeled mullet (Liza carinata Valenciennes, 1836) from Yelkoma Lagoon, northeastern Mediterranean region. So, the levels of cadmium, cobalt, chromium, copper, iron, manganese, nickel, lead, and zinc in tissues of specimens from the lagoon were determined by inductively coupled plasma optical emission spectrometer. Concentrations of metals in muscles of the examined species ranged from 0.10 to 0.47 mg kg???1 for cadmium, 0.10 to 0.43 mg kg???1 for cobalt, 0.17 to 0.72 mg kg???1 for chromium, 0.62 to 1.03 mg kg???1 for copper, 28.9 to 52.3 mg kg???1 for iron, 0.75 to 0.96 mg kg???1 for manganese, 0.11 to 0.57 mg kg???1 for nickel, 0.19 to 0.47 mg kg???1 for lead, and 6.01 to 13.9 mg kg???1 for zinc, respectively. Additionally, metal concentrations in muscles of fish were assessed for human uses according to provisional tolerable weekly intake and provisional tolerable daily intake. 相似文献