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1.
Mughal Nafessa Kashif Maryam Arif Asma Guerrero John William Grimaldo Nabua Wilson C. Niedbała Gniewko 《Environmental science and pollution research international》2021,28(46):65116-65126
Environmental Science and Pollution Research - This study aims to re-examine the impacts of monetary and fiscal policy on environmental quality in ASEAN countries from 1990 to 2019. We utilized the... 相似文献
2.
Simas Angélica Mores Rúbia Steffens Juliana Dallago Rogério Marcos Kunz Airton Michelon William Fongaro Gislaine Viancelli Aline 《Environmental Chemistry Letters》2019,17(1):495-499
Environmental Chemistry Letters - Swine production generates large volumes of wastewater, rich in organic matter, nutrients and pathogens. Electrodisinfection is used to remove organic matter and... 相似文献
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We undertook a detailed analysis of the lipid composition ofSolemya velum (Say), a bivalve containing endosymbiotic chemoautotrophic bacteria, in order to determine the presence of lipid biomarkers of endosymbiont activity. The symbiont-free clamMya arenaria (L.) and the sulfur-oxidizing bacteriumThiomicrospira crunogena (Jannasch et al.) were analyzed for comparative purposes. The
13C ratios of the fatty acids and sterols were also measured to elucidate potential carbon sources for the lipids of each bivalve species. Both fatty acid and sterol composition differed markedly between the two bivalves. The lipids ofS. velum were characterized by large amounts of 18: 17 (cis-vaccenic acid), 16:0, and 16 : 17 fatty acids, and low concentrations of the highly unsaturated plant-derived fatty acids characteristic of most marine bivalves. Cholest-5-en-3-ol (cholesterol) accounted for greater than 95% of the sterols inS. velum. In contrast,M. arenaria had fatty acid and sterol compositions similar to typical marine bivalves and was characterized by large amounts of the highly unsaturated fatty acids 20 : 53 and 22 : 63 and a variety of plant-derived sterols. The fatty acids ofT. crunogena were similar to those ofS. velum and were dominated by 18:17, 16:0 and 16:17 fatty acids. Thecis-vaccenic acid found inS. velum is almost certainly symbiontderived and serves as a potential biomarker for symbiontlipid incorporation by the host. The high concentrations ofcis-vaccenic acid (up to 35% of the total fatty acid content) in both symbiont-containing and symbiont-free tissues ofS. velum demonstrate the importance of the endosymbionts in the lipid metabolism of this bivalve. The presence ofcis-vaccenic acid in all the major lipid classes ofS. velum demonstrates both incorporation and utilization of this compound. The
13C ratios of the fatty acids and sterols ofS. velum were significantly lighter (–38.4 to –45.3) than those ofM. arenaria (–23.8 to – 24.2) and were similar to the values found for the fatty acids ofT. crunogena (–45); this suggests that the lipids ofS. velum are either derived directly from the endosymbionts or are synthesized using endosymbiontderived carbon.Woods Hole Oceanographic Institution Contribution No. 7356Please address all correspondence and reprint requests to Dr Conway at her present address: Department of Biological Sciences, University of Pittsburgh, Pennsylvania 15260, USA 相似文献
6.
Ronald Fuge Ian M. S. Laidlaw William T. Perkins Kerry P. Rogers 《Environmental geochemistry and health》1991,13(2):70-75
The many abandoned base metal mines of the mid-Wales ore field are sources of extensive pollution. Some of the mineralised veins contain large amounts of pyrite and marcasite and oxidative weathering of these produces sulphuric acid resulting in very acidic mine drainage waters. In addition, the spoil tips associated with these mines can contain abundant iron sulphides. Drainage waters from these sources have pH values as low as 2.6 and are heavily contaminated with metals such as Al, Zn, Cd and Ni.Two of the main rivers of the area, the Rheidol and Ystwyth, intercept heavily contaminated acidic drainage which has a marked effect on water quality. The Rheidol contains over 100 g L–1 Zn for 16 km downstream of the acid water influx. This level is over three times the recommended EEC limit for Zn in salmonoid waters of low hardness. 相似文献
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J. Christian Franson William L. Hohman Joseph L. Moore Milton R. Smith 《Environmental monitoring and assessment》1996,43(2):181-188
We used 363 blood samples collected from wild canvasback dueks (Aythya valisineria) at Catahoula Lake, Louisiana, U.S.A. to evaluate the effect of sample storage time on the efficacy of erythrocytic protoporphyrin as an indicator of lead exposure. The protoporphyrin concentration of each sample was determined by hematofluorometry within 5 min of blood collection and after refrigeration at 4 °C for 24 and 48 h. All samples were analyzed for lead by atomic absorption spectrophotometry. Based on a blood lead concentration of 0.2 ppm wet weight as positive evidence for lead exposure, the protoporphyrin technique resulted in overall error rates of 29%, 20%, and 19% and false negative error rates of 47%, 29% and 25% when hematofluorometric determinations were made on blood at 5 min, 24 h, and 48 h, respectively. False positive error rates were less than 10% for all three measurement times. The accuracy of the 24-h erythrocytic protoporphyrin classification of blood samples as positive or negative for lead exposure was significantly greater than the 5-min classification, but no improvement in accuracy was gained when samples were tested at 48 h. The false negative errors were probably due, at least in part, to the lag time between lead exposure and the increase of blood protoporphyrin concentrations. False negatives resulted in an underestimation of the true number of canvasbacks exposed to lead, indicating that hematofluorometry provides a conservative estimate of lead exposure.The U.S. Government's right to retain a non-exclusive, royalty-free licence in and to any copyright is acknowledgedDeceased 相似文献
8.
Scenario Analysis for the San Pedro River, Analyzing Hydrological Consequences of a Future Environment 总被引:1,自引:0,他引:1
Kepner WG Semmens DJ Bassett SD Mouat DA Goodrich DC 《Environmental monitoring and assessment》2004,94(1-3):115-127
Studies of future management and policy options based on different assumptions provide a mechanism to examine possible outcomes and especially their likely benefits and consequences. The San Pedro River in Arizona and Sonora, Mexico is an area that has undergone rapid changes in land use and cover, and subsequently is facing keen environmental crises related to water resources. It is the location of a number of studies that have dealt with change analysis, watershed condition, and most recently, alternative futures analysis. The previous work has dealt primarily with resources of habitat, visual quality, and groundwater related to urban development patterns and preferences. In the present study, previously defined future scenarios, in the form of land-use/land-cover grids, were examined relative to their impact on surface-water conditions (e.g., surface runoff and sediment yield). These hydrological outputs were estimated for the baseline year of 2000 and predicted twenty years in the future as a demonstration of how new geographic information system-based hydrologic modeling tools can be used to evaluate the spatial impacts of urban growth patterns on surface-water hydrology. 相似文献
9.
A peat core from an ombrotrophic bog in Switzerland provides the first complete, long-term record (14 500 years) of atmospheric Ag and Tl deposition. The lack of enrichment of Ag and Tl in the basal peat layer shows that mineral dissolution in the underlying sediments has not contributed measurably to the Ag and Tl inventories in the peat column, and that Ag and Tl were supplied exclusively by atmospheric deposition. The temporal and spatial distribution of modern peaks in Ag and Tl concentrations are similar to those of Pb which is known to be immobile in peat profiles. Silver and Tl, therefore, are effectively immobile in the peat bog also, allowing an atmospheric deposition chronology to be reconstructed. Silver concentrations vary by up to 114x and Tl up to 241x. While Holocene climate change and land use history can explain the variation in metal concentrations and enrichment factors (EF) in ancient peats (i.e. pre-dating the Roman Period), anthropogenic sources have to be invoked to explain the very high EF values (up to 123 in the case of Ag and 12 in the case of Tl) in peat samples since the middle of the 19th Century. The "natural background" EF of Tl in ancient peats is remarkably close to unity, indicating a lack of significant enrichment of this element in atmospheric aerosols due to chemical weathering of crustal rocks. Silver, on the other hand, shows a pronounced enrichment from 8030 to 5230 (14)C years BP (12x compared to crustal rocks); this may be due to weathering phenomena or biological processes, both of which are driven by climate. Even compared to the natural enrichment of Ag during the mid-Holocene, however, the enrichments of Ag and Tl in modern peats from the Industrial Period are at least an order of magnitude greater. The Pb/Ag and Tl/Ag ratios show that Pb and Tl are preferentially released, compared to Ag, during smelting of argentiferous Pb ores mined during the Roman and Medieval Periods. 相似文献
10.
Thomas J. Stohlgren Dan Binkley Thomas T. Veblen William L. Baker 《Environmental monitoring and assessment》1995,36(1):1-25
Monitoring long-term change in forested landscapes is an intimidating challenge with considerable practical, methodological, and theoretical limitations. Current field approaches used to assess vegetation change at the plot-to-stand scales and nationwide forest monitoring programs may not be appropriate at landscape scales. We emphasize that few vegetation monitoring programs (and, thus, study design models) are designed to detect spatial and temporal trends at landscape scales. Based primarily on advice from many sources, and trial and error, we identify 14 attributes of a reliable long-term landscape monitoring program: malpractice insurance for landscape ecologists. The attributes are to: secure long-term funding and commitment; develop flexible goals; refine objectives; pay adequate attention to information management; take an experimental approach to sampling design; obtain peer-review and statistical review of research proposals and publications; avoid bias in selection of long-term plot locations; insure adequate spatial replication; insure adequate temporal replication; synthesize retrospective, experimental, and related studies; blend theoretical and empirical models with the means to validate both; obtain periodic research program evaluation; integrate and synthesize with larger and smaller scale research, inventory, and monitoring programs; and develop an extensive outreach program. Using these 14 attributes as a guide, we describe one approach to assess the potential effect of global change on the vegetation of the Front Range of the Colorado Rockies. This self-evaluation helps identify strengthes and weaknesses in our program, and may serve the same role for other landscape ecologists in other programs. 相似文献