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71.
72.
Four decades of glacier mass balance observations in the Indian Himalaya   总被引:2,自引:0,他引:2  
Understanding the glacier mass balance is necessary to explain the rate of shrinkage and to infer the impact of climate change. The present study provides an overview of the glacier mass balance records by glaciological, geodetic, hydrological and accumulation-area ratio (AAR) and specific mass balance relationship methods in the Indian Himalaya since 1970s. It suggests that the mass balance measurements by glaciological methods have been conducted for ten glaciers in the western Himalaya, four glaciers in the central Himalaya and one in the eastern Himalaya. Hydrological mass balance has been conducted only on Siachen Glacier from 1987 to 1991. Geodetic method has been attempted for the Lahaul–Spiti region for a short time span during 1999–2011 and Hindu Kush–Karakoram–Himalaya region from 2003 to 2008. We compared in situ specific balance data series with specific mass balance derived from AAR and specific mass balance relationship. The results derived from existing and newly presented regression model based on AAR and specific mass balance relationship induced unrealistic specific mass balance for several glaciers. We also revised AAR0 and ELA0 based on available in situ AAR and specific mass balance data series of Indian Himalayan glaciers. In general, in situ specific and cumulative specific mass balance observed over different regions of the Indian Himalayan glaciers shows mostly negative mass balance years with a few positive ones during 1974–2012. On a regional level, the geodetic studies suggest that on the whole western, the central and the eastern Himalaya experienced vast thinning during the last decade (2000s). Conversely, Karakoram region showed slight mass gain during almost similar period. However, the glaciological, hydrological and geodetic mass balance data appear to exhibit short time series bias. We therefore recommend creation of benchmark glaciers network for future research to determine the impact of climate change on the Himalayan cryosphere.  相似文献   
73.
Human breast milk offers the optimal nutrition for all infants and have been widely used in biomonitoring programs to assess human exposure to lipophylic environmental contaminants such as polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF) and polychlorinated biphenyls (PCB). There are no previous reports from Turkey on chemically determined levels of PCDDs, PCDFs, and PCBs in human breast milk expressed as World Health Organization (WHO) toxic equivalents (TEQ). To get an overview of the levels of these contaminants in Turkish human milk, samples from 51 Turkish women living in the Ankara, İstanbul, Antalya, Kahramanmaraş, and Afyon provinces were analyzed by high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) throughout 2007. The mean concentrations of WHOPCDD/F-TEQ and WHOPCB-TEQ of all samples from the five regions were 7.5 and 3.1 pg g−1 on a lipid basis, respectively. PCDD/F concentrations ranged between 0.78 and 29.3 pg WHO-TEQ g−1 fat (1.7 and 36.2 pg WHO-TEQ g−1 fat, respectively, including PCB). Of the five studied locations, the lowest levels of ∑TEQs (PCDD/F + PCB) were found in the Afyon (6.8 pg WHO-TEQ g−1 fat) and the highest in the Antalya (15.6 pg WHO-TEQ g−1 fat) province. The results have been discussed in terms of regions and PCDD/F and PCBs for which analyses had been made. The mean levels of PCDD/Fs and PCBs in Turkish human milk are comparable to that found in other countries.  相似文献   
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75.
The aim of this study was to determine the total metal accumulation (aluminium, copper, manganese, lead, cadmium and iron) in different organs and eggs of Astacus leptodactylus (Eschscholtz, 1823) and sediments total metal contents (aluminium, copper, manganese, lead, cadmium, iron, zinc, chromium, nickel) in Lake Terkos. Water and sediment samples were collected from two stations at two different depths (1 and 2 m) of Lake Terkos in May 2008. Crayfish samples were collected by trammel net at the same region. Primary hydrographic conditions, such as temperature (13.6–19.4°C), salinity (0.27–0.34‰), dissolved oxygen (7.04–12.30 mg l???1) and pH (7.42–8.51), were recorded for each sampling point. Moreover, the total organic carbon (1.65–5.44%) and the total calcium carbonate contents (19.44–41.16%) of sediment samples were determined. According to the Turkish Food Codex (J Zool 26:283–288, 2002), the maximum allowable Pb and Cd levels in crayfish are 0.5 mg/kg wet weight. Accordingly, the Pb and Cd levels determined in A. leptodactylus samples are below this limit. However, when compared with the acceptable metal limits defined by WHO, Australian National Health and Medical Research Council and Ministry of Agriculture in United Kingdom (UK), it is clear that the Cu level is at the limit and the Cd results exceed the limit. When the metal contents in sediment samples from Lake Terkos are examined, it is seen that the Al, Fe, Mn, Ni and Cu contents are lower while Zn, Cr, Cd and Pb contents are higher than the crustal average values. The high values draw attention to the land-based domestic and industrial inputs. Lake Terkos sediments have high enrichment factors (EF) of Zn, Cr, Cd and Pb metals which corroborate this result. The low EFs of Fe, Ni and Cu are due to the natural (terrigeneous) inputs. Additionally, there is no Al, Fe, Ni and Cu metal enrichment in these lake sediments because of the low contamination factor (CF) values. However, it is moderately contaminated by Zn, Cr and Pb, and heavily contaminated by Cd.  相似文献   
76.
77.
High temperature alkaline chemical liquids have caused injuries and hazardous situations in Finnish pulp manufacturing mills. There are no requirements and/or test method standards concerning protection against high temperature alkaline chemical splashes. This paper describes the test method development process to test and identify materials appropriate for hot liquid chemical hazard protection. In the first phase, the liquid was spilled through a stainless steel funnel and the protection performance was evaluated using a polyvinyl chloride (PVC) film under the test material. After several tentative improvements, a graphite crucible was used for heating and spilling the chemical, and a copper-coated K-type thermometer with 4 independent measuring areas was designed to measure the temperature under the material samples. The thermometer was designed to respond quickly so that peak temperatures could be measured. The main problem was to keep the spilled amount of chemical constant, which unfortunately resulted in significant variability in data.  相似文献   
78.
The concentrations of 41 phenols in leachates from 38 municipal solid waste (MSW) landfill sites in Japan were measured. The main phenols detected in leachates were phenol, three cresols, 4-tert-butylphenol, 4-tertoctylphenol, 4-nonylphenol, bisphenol A, and some chlorophenols. The concentration levels of phenols were affected by the pH values of the leachates and the different types of landfill waste. The origins of phenol and p-cresol were considered to be incineration residues, and the major origin of 4-tert-butylphenol, bisphenol A, and 2,4,6-trichlorophenol was considered to be solidified fly ash. In contrast, the major origins of 4-tert-octylphenol and 4-nonylphenol were considered to be incombustibles. The discharge of leachates to the environment around MSW landfill sites without water treatment facilities can cause environmental pollution by phenols. In particular, the disposal of incineration residues including solidified fly ash and the codisposal of solidified fly ash and incombustibles might raise the possibility of environmental pollution. Moreover, the discharge of leachates at pH values of 9.8 or more could pollute the water environment with phenol. However, phenol, 4-nonylphenol, and bisphenol A can be removed to below the con centration levels that impact the environment around landfill sites by a series of conventional water treatment processes.  相似文献   
79.
Frequent monitoring and relatively high fines are usually necessary to bring about improvements in environmental quality, but more challenging for many countries with limited human, material, and financial resources is to put them into practice. This paper developed a three-group model of a state-dependent enforcement in a repeated game to improve the policy implementation under limited inspection capacities. A certain number of firms are grouped (group 1, group 2, group 3) for different supervision intensity (e.g., the order of inspection probability corresponding to each group is p 1?<?p 2?<?p 3) based on their environmental performance. The optimal policy parameters, such as inspection probability of each group and the probability that a firm found in compliance is moved to a better reputation group, were obtained as the basis for regulator’s policy making. Numerical simulations indicated that the three-group inspection regime can significantly increase compliance rate as compared with static enforcement with the same monitoring probability. Among the number of firms in each group under steady state conditions, group 2 had the most, group 1 was the second, and group 3 had the smallest. Analysis and prediction of a three-group reputation example provided a good experiment for the model. The results give a practical reference for the policy makers with inspection capacity constraints to achieve higher compliance rate.  相似文献   
80.
Kasur is one of the hubs of leather industry in the Punjab, Pakistan, where chrome tanning method of leather processing is extensively being used. Chromium (Cr) accumulation levels in the irrigation water, soil, and seasonal vegetables were studied in three villages located in the vicinity of wastewater treatment plant and solid waste dumping site operated by the Kasur Tanneries Waste Management Agency (KTWMA). The data was interpreted using analysis of variance (ANOVA), clustering analysis (CA), and principal component analysis (PCA). Interpolated surface maps for Cr were generated using the actual data obtained for the 30 sampling sites in each of the three villages for irrigation water, soil, and seasonal vegetables. The level of contamination in the three villages was directly proportional to their distance from KTWMA wastewater treatment plant and the direction of water runoff. The highest level of Cr contamination in soil (mg kg?1) was observed at Faqeeria Wala (37.67), intermediate at Dollay Wala (30.33), and the least in Maan (25.16). A gradational variation in Cr accumulation was observed in the three villages from contaminated wastewater having the least contamination level (2.02–4.40 mg L?1), to soil (25.16–37.67 mg kg?1), and ultimately in the seasonal vegetable crops (156.67–248.33 mg kg?1) cultivated in the region, having the highest level of Cr contamination above the permissible limit. The model used not only predicted the current situation of Cr contamination in the three villages but also indicated the trend of magnification of Cr contamination from irrigation water to soil and to the base of the food chain. Among the multiple causes of Cr contamination of vegetables, soil irrigation with contaminated groundwater was observed to be the dominant one.  相似文献   
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