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Environmental Science and Pollution Research - The sun is the primary source of life on the earth. The heating effect of the sun provides a more fruitful environment for mankind. In addition, solar...  相似文献   
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Human hair is frequently used as a bioindicator of mercury exposure. Mercury (Hg) has for centuries been a useful metal in a variety of applications. Unfortunately, this usefulness is counterbalanced by its neurotoxicological health impact. The US Environmental Protection Agency recommends keeping the hair Hg level <1.0 µg/g. Therefore, an investigation has been performed in order to ascertain the hair Hg levels among the people living at the terai belt of North India. Hair samples were collected from 111 individuals and were placed in an identified plastic bag, stapled to prevent the shift of the hair strand. Samples were analyzed by combustion, gold amalgamation, atomic absorption spectrometry (C-GA-AAS). The mean Hg level in hair was 0.28 µg/g for the whole group ranging from 0.0012 to 1.9091 µg/g. The mean hair Hg levels were 0.16 µg/g for men and 0.12 µg/g for women, indicating that men had higher hair Hg levels than women. Total hair Hg was found to be significantly associated with age, gender and fish consumption frequency. 98 % of the total sample had hair Hg concentrations less than 1.0 µg/g, i.e, within safe dose, whereas only 2 % had Hg concentrations greater than 1.0 µg/g, thereby exceeding the safe dose.

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Environmental Science and Pollution Research - The discharge of emerging pollutants, such as beta-blockers (BB), has been recognized as one of the major threats to the environment due to the...  相似文献   
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Environmental Science and Pollution Research - The major global concern on energy is focused on conventional fossil resources. The burning of fossil fuels is an origin of greenhouse gas emissions...  相似文献   
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Land use change can significantly affect the provision of ecosystem services and the effects could be exacerbated by projected climate change. We quantify ecosystem services of bioenergy‐based land use change and estimate the potential changes of ecosystem services due to climate change projections. We considered 17 bioenergy‐based scenarios with Miscanthus, switchgrass, and corn stover as candidate bioenergy feedstock. Soil and Water Assessment Tool simulations of biomass/grain yield, hydrology, and water quality were used to quantify ecosystem services freshwater provision (FWPI), food (FPI) and fuel provision, erosion regulation (ERI), and flood regulation (FRI). Nine climate projections from Coupled Model Intercomparison Project phase‐3 were used to quantify the potential climate change variability. Overall, ecosystem services of heavily row cropped Wildcat Creek watershed were lower than St. Joseph River watershed which had more forested and perennial pasture lands. The provision of ecosystem services for both study watersheds were improved with bioenergy production scenarios. Miscanthus in marginal lands of Wildcat Creek (9% of total area) increased FWPI by 27% and ERI by 14% and decreased FPI by 12% from the baseline. For St. Joseph watershed, Miscanthus in marginal lands (18% of total area) improved FWPI by 87% and ERI by 23% while decreasing FPI by 46%. The relative impacts of land use change were considerably larger than climate change impacts in this paper. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.  相似文献   
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Several biofuel cropping scenarios were evaluated with an improved version of Soil and Water Assessment Tool (SWAT) as part of the CenUSA Bioenergy consortium for the Boone River Watershed (BRW), which drains about 2,370 km2 in north central Iowa. The adoption of corn stover removal, switchgrass, and/or Miscanthus biofuel cropping systems was simulated to assess the impact of cellulosic biofuel production on pollutant losses. The stover removal results indicate removal of 20 or 50% of corn stover in the BRW would have negligible effects on streamflow and relatively minor or negligible effects on sediment and nutrient losses, even on higher sloped cropland. Complete cropland conversion into switchgrass or Miscanthus, resulted in reductions of streamflow, sediment, nitrate, and other pollutants ranging between 23‐99%. The predicted nitrate reductions due to Miscanthus adoption were over two times greater compared to switchgrass, with the largest impacts occurring for tile‐drained cropland. Targeting of switchgrass or Miscanthus on cropland ≥2% slope or ≥7% slope revealed a disproportionate amount of sediment and sediment‐bound nutrient reductions could be obtained by protecting these relatively small areas of higher sloped cropland. Overall, the results indicate that all biofuel cropping systems could be effectively implemented in the BRW, with the most robust approach being corn stover removal adopted on tile‐drained cropland in combination with a perennial biofuel crop on higher sloped landscapes. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.  相似文献   
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The objective of the present study was to evince the long-term changes after natural revegetation and experimental revegetation of the coal mine spoils with respect to total plant biomass, available plant nutrients, nitrogen transformation and microbial biomass N (MBN) in dry tropical environment of India. Total plant biomass (above- and below-ground), plant available nitrogen, soil nitrogen mineralization and microbial biomass N (MBN) were studied for 2 years in 5 and 10 years old naturally vegetated and revegetated coal mine spoils, and dry tropical forest ecosystem of India. In forest ecosystem, the above ground biomass values ranged from 3,520 to 3,630 kg ha(-1) and belowground from 6,280 to 6,560 kg ha(-1). Plant available nitrogen ranged from 16.76 to 23.21 microg g(-1), net N-mineralization from 9.8 to 48.53 microg g(-1) month(-1) and MBN from 26.4 to 80.02 microg g(-1). In naturally revegetated mine spoil, the above ground biomass values ranged from 1,036 to 1,380 kg ha(-1) and belowground from 2,538 to 3,380 kg ha(-1). Plant available nitrogen ranged from 7.33-17.14 microg g(-1), net N-mineralization from 3.1 to 12.46 microg g(-1) month(-1) and MBN from 14.2 to 35.44 microg g(-1). In revegetated mine spoil, the above ground biomass values ranged from 1,224 to 1,678 kg ha(-1) and belowground from 2,870 to 4,130 kg ha(-1). Plant available nitrogen ranged from 9.4 to 18.83 microg g(-1), net N-mineralization from 4.2 to 16.2 microg g(-1) month(-1) and MBN from 21.6 to 42.6 microg g(-1). The mean plant biomass values in 5 and 10 years mine spoils was lower compared to forest ecosystem by 2.5 and 2 times, respectively. N-mineralization value in 5 year mine spoil was 3.5 times lower and in 10 years mine spoil 2 times lower compared to forest ecosystem. The MBN value was about 2 times lower in both 5 and 10 year mine spoils compared to native forest. MBN was positively related to the re-vegetation age of the mine spoil.  相似文献   
70.
Airborne particulates (PM10) from four different areas within Agra city (a semi-arid region) were collected using respirable dust samplers during the winter season (Nov. 2005–Feb 2006) and were then extracted with methylene chloride using an automated Soxhlet Extraction System (Soxtherm®). The extracts were analyzed for 17 target polycyclic aromatic hydrocarbons (PAHs) and the heterocycle carbazole. The average concentration of total PAH (TPAH) ranged from 8.04 to 97.93 ng m???3. The industrial site had the highest TPAH concentration followed by the residential, roadside, and agricultural sites. Indeno(1,2,3-cd)pyrene, benzo(g,h,i)perylene, and benzo(b)fluoranthene were the predominant compounds found in the samples collected from all of the sites. The average B(a)P-equivalent exposure, calculated by using toxic equivalent factors derived from literature and the USEPA, was approximately 7.6 ng m???3. Source identification using factor analysis identified prominent three, four, four, and four probable factors at industrial, residential, roadside, and agricultural sites, respectively.  相似文献   
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