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351.
Monitoring land use and land cover change (LUCC) and understanding forest cover dynamics is extremely important in sustainable development and management of forest ecosystems. This study analyzed the spatial and temporal pattern of LUCC in the Yaln?zçam and U?urlu forest planning units which are located in the northeast corner of Turkey. The investigation also evaluates the temporal changes of the spatial structure of forest conditions through the spatial analysis of forest-cover type maps from 1972 and 2005 using geographical information systems and FRAGSTATSTM. As an overall change between 1972 and 2005, there was a net increase of 1,823 ha in forested areas, and cumulative forest improvement accounted for 2.06 %. In terms of spatial configuration, the landscape structure in the study area changed substantially over the 33-year study period, resulting in fragmentation of the landscape as indicated by large patch numbers and smaller mean patch sizes, owing to heavy grazing, illegal cutting, and uncontrolled stand treatments.  相似文献   
352.
The Mechanistic Indicators of Childhood Asthma (MICA) study in Detroit, Michigan introduced a participant-based approach to reduce the resource burden associated with collection of indoor and outdoor residential air sampling data. A subset of participants designated as MICA-Air conducted indoor and outdoor residential sampling of nitrogen dioxide (NO2), volatile organic compounds (VOCs), and polycyclic aromatic hydrocarbons (PAHs). This participant-based methodology was subsequently adapted for use in the Vanguard phase of the U.S. National Children’s Study. The current paper examines residential indoor and outdoor concentrations of these pollutant species among health study participants in Detroit, Michigan.Pollutants measured under MICA-Air agreed well with other studies and continuous monitoring data collected in Detroit. For example, NO2 and BTEX concentrations reported for other Detroit area monitoring were generally within 10–15% of indoor and outdoor concentrations measured in MICA-Air households. Outdoor NO2 concentrations were typically higher than indoor NO2 concentration among MICA-Air homes, with a median indoor/outdoor (I/O) ratio of 0.6 in homes that were not impacted by environmental tobacco smoke (ETS) during air sampling. Indoor concentrations generally exceeded outdoor concentrations for VOC and PAH species measured among non-ETS homes in the study. I/O ratios for BTEX species (benzene, toluene, ethylbenzene, and m/p- and o-xylene) ranged from 1.2 for benzene to 3.1 for toluene. Outdoor NO2 concentrations were approximately 4.5 ppb higher on weekdays versus weekends. As expected, I/O ratios pollutants were generally higher for homes impacted by ETS.These findings suggest that participant-based air sampling can provide a cost-effective alternative to technician-based approaches for assessing indoor and outdoor residential air pollution in community health studies. We also introduced a technique for estimating daily concentrations at each home by weighting 2- and 7-day integrated concentrations using continuous measurements from regulatory monitoring sites. This approach may be applied to estimate short-term daily or hourly pollutant concentrations in future health studies.  相似文献   
353.
Soil and air samples of seven different localities around Hamitabat Thermic Power Plant, 10 km far away from Luleburgaz/Kirklareli (Turkey), were taken between the years 2003 and 2004 with seasonal intervals. The samples were brought to the laboratory and their microfungal identifications were done. From the air samples, 737 microfungi colonies were isolated comprising 26 species belonging to eight genera. From soil samples, 170.6 × 104 colony-forming unit (CFU)/g was isolated from 33 species belonging to 16 genera. The most isolated genus from air samples was Alternaria (324 CFU, 43.96%), followed by Cladosporium (208 CFU, 25.52%) and Phoma (44 CFU, 5.40%). Penicillium was the most isolated genus from the soil samples with a value of 560,000 CFU/g (32.8%), followed by Fusarium (226,000 CFU/g, 13.12%) and Aspergillus (154,000 CFU/g, 9.03%). Among these species, Alternaria citri and Alternaria alternata are the most abundant species in air with 164 and 107 CFU, respectively, whereas Fusarium graminearum and Penicillium citrinum are the most abundant species in soil with CFU per gram values of 17.8 × 104 and 1.3 × 105. Correlation analysis was applied to determine whether or not there was a relationship between colony number of isolated fungal genera and meteorological factors. Some parameters of soil samples’ incontent during the research period were calculated using a computer analysis program. From the air samples, a positive correlation was found between relative humidity and Alternaria colonial counts and Cladosporium spore counts (r?=?0.912 and r?=?1.000, respectively). Similarly, with the analysis of soil samples, a positive correlation between colonial counts of Alternaria and soil pH and a positive correlation between colonial counts of Aspergillus and Penicillium and salt percentage concentration of soil were found.  相似文献   
354.
Micronuclei tests is a system of mutagenicity testing used for determining the pollution and chemicals causing changes in DNA fragments such as micronuclei in the cytoplasm of interphase cells. Damage caused on the DNA by genotoxic pollutants is the first consequence occurring in the aquatic organisms. Thus, it was attempted to determine whether pollution affected the erythrocytes and gills of fish Gobius niger and haemolymph and gills of mussels Mytilus galloprovincialis living in Izmir Bay at the level of DNA by the means of micronuclei (MN) test. Organisms used in the MN test were collected from seven locations (Alsancak, Alaybey Shipyard, Karsiyaka, Bostanli, Göztepe, Konak and Pasaport) which are known as the most polluted part of inner Bay of Izmir (Western Coast of Turkey). According to the results of the present study, frequency of MN was found at high level in Alaybey Shipyard and Pasaport where wastes from existing dockyard contributed to high level of pollution. In conclusion, this study indicates that the micronuclei test gives sensitive results in monitoring the pollution, especially the pollution of harbor, and thus it might be used as standard method in regular monitoring of pollution of coastal ecosystem.  相似文献   
355.
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   
356.
Achanthobrama marmid (thorn-bream) (n:24), Chondrostoma regium (nose-carp) (n:33) and Silurus glanis (wels) (n:21), and Cyprinus carpio (carp) (n:30) were collected from Sır Dam Lake in Kahramanmaraş Province. The iron (Fe), manganese (Mn), cobalt (Co), nickel (Ni), and lead (Pb) levels were determined in the total of 108 fish samples by Atomic Absorption Spectrophotometer. The concentrations of heavy metals were expressed as mg kg−1 wet weight of tissue. The mean Fe and Mn levels of muscle and gill of C. carpio were 0.8–5.71 and 0.30–1.96, respectively. The mean of the Fe and Mn levels of muscle and gill of A. marmid were 1.22, 5.07 and 0.38, 0.85 mg kg−1, respectively. The ranges of mean concentrations of Fe and Mn levels in muscle and gill of C. regium were 0.91, 5.61 and 0.27, 3.42 mg kg−1, respectively. The mean value of Fe in S. glanis gill was 1.03, which of Mn was 0.17 mg kg−1. Fe, Mn, Co, Ni, and Pb were not detected in the muscle of S. glanis. The mean values for Co in muscle of thorn-bream, carp, and nose-carp were 0.005, 0.01, 0.0 mg kg−1, respectively. Nickel values in the muscle were ranged between 0.38 and 1.93 in thorn-bream, 0.06 and 1.34 in carp, 0.14 and 1.89 in nose-carp, in that order. The mean Pb levels of muscle and gill of A. marmid were 0.14 and 0.29 mg kg−1, respectively. The mean values of Pb concentration of muscle and gill for C. carpio were 0.13 and 0.50 mg kg−1, respectively. In C. regium mean values for Pb in muscle and gill were 0.06 and 0.06 mg kg−1, respectively. The mean value of Pb in S. glanis gill was 0.42, ranged between 0.0–0.92 mg kg−1.  相似文献   
357.
Cindoruk SS 《Chemosphere》2011,82(1):78-87
Air concentrations of organochlorine pesticides (OCPs) were measured at four different sites in Bursa, Turkey to determine current levels. For this purpose, about 35 samples were collected from June 2008 to June 2009 using a high volume air sampler (HVAS) equipped with particle and gas-phase units. Ten OCP compounds (alpha-, beta-, gamma-, delta-hexachlorocyclohexane, Heptachlor epoxide, Endrin, Endosulfan beta, Endrin aldehyde, p,p′-DDT and Methoxychlor) were reported within the scope of this study. The average concentrations of total (particle + gas) ∑OCPs were 550.9 ± 277.6 pg m−3 (coastal), 1030.7 ± 453.5 pg m−3 (urban/traffic), 519.7 ± 277.5 pg m−3 (semi-rural) and 722.8 ± 351.8 pg m−3 (urban/residential). The individual OCP concentrations were in line with reported concentrations. The maximum particle and gas-phase concentrations were determined for Endosulfan beta and beta-HCH for all sites, respectively. Available gas/particle partitioning models were applied in order to investigate the compatibility of the experimental data and the significant relationships were observed.  相似文献   
358.
The levels of heavy metals were determined in the water of Bendimahi River Basin, statistically analysed and compared to natural gross radioactivity concentration. Fifteen samples of water were collected from Bendimahi River and Van Lake for two seasons in 2005. Water samples were analyzed for eight trace elements and concluded together with gross-alpha and gross-beta radioactivity concentrations. Atomic absorption spectrometry (AAS) was used to determine the concentrations of heavy metals in water samples collected from Bendimahi River basin. Correlation analysis was made for radioactivity and heavy metal concentrations and the Pearson correlation coefficients between gross-alpha and gross-beta radioactivity and heavy metal were determined. The concentrations of all metals were found to be higher than WHO, EC, EPA and TSE-266 guidelines for drinking water, except for Zn and Cu. Generally, the heavy metal concentrations in water samples obtained in May and in August were found to be in sequence of Fe>Zn>Pb>Cr>Cu>Mn>Co>Cd and Fe>Zn>Cu>Pb>Cr>Mn>Co>Cd, respectively. The gross-alpha and gross-beta activity concentration varies between 0.063 and 0.782, 0.021 and 0.816 Bq l(-1) in samples collected in May, and 0.009 and 0.037, 0.081 and 3.116 Bq l(-1) in samples collected in August.  相似文献   
359.
There is an increasingly need to assess the contaminant levels in fish as indicators of the health and well-being of both the fish and their consumers, including humans. Fish samples were collected through the coastal waters of Turkey and the contents of cadmium, copper, chrome, copper, iron, manganese, nickel, zinc and lead in the liver and muscle tissues were determined by ICP-AES. The highest levels of each metal were found in the liver and this was followed by the muscle in both species. Among the metals analyzed, Cu, Zn and Fe were the most abundant in the different tissues while Cd and Pb were the least abundant both in Mullus barbatus (red mullet) and Merlangius merlangus (whiting). Regional changes in metal (Cd, Cu, Pb, Fe and Zn) concentration were observed in the tissues of both species, but these variations may not influence consumption advisories.  相似文献   
360.
Patterns of epilithic diatom species distribution in relation to environmental variables from 12 sampling sites on the main stream and some of its tributaries in the Nilüfer Stream Basin were determined using multivariate statistical techniques. The stream basin has been heavily influenced by anthropogenic effects. The upper part of the basin that is distant from pollution sources mostly has a spring water quality, while the lower part where the stream flows through the urban area and receives domestic and industrial wastewater has a quite low quality. Ordination techniques using both diatom taxa and 21 environmental variables revealed non- to slightly polluted upper basin sites and highly polluted lower basin sites along the stream. The results showed that the stream catchment is polluted gradually from upstream to downstream and that most of the downstream sites have very low water quality especially in summer months. A total of 134 epilithic diatom taxa belonging to 50 genera were recorded for 12 sample sites. Partial CCA results indicated that water temperature (T), discharge (Q), and total phosphorus (TP) were the most important variables affecting the distribution of diatom species. Unpolluted or slightly polluted upper basin sites were dominated by Achnanthidium minutissimum, Cocconeis placentula var. euglypta, Gomphonema olivaceum, and Navicula tripunctata. Highly polluted lower basin sites were characterized by high levels of organic and inorganic matters and low dissolved oxygen (DO) values. Species widespread in the highly polluted lower basin sites such as Nitzschia umbonata, Nitzschia amphibia, Nitzschia capitellata, Nitzschia palea, Nitzschia paleacea, Luticola mutica, and Stephanodiscus niagarae were mostly related to pollution indicator variables such as ammonium nitrogen (NH4 +–N), sodium (Na+), total phosphorus (TP), and total organic matter (TOM).  相似文献   
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