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171.
Agricultural management practices that enhance C sequestration, reduce greenhouse gas emission (nitrous oxide [N?O], methane [CH?], and carbon dioxide [CO?]), and promote productivity are needed to mitigate global warming without sacrificing food production. The objectives of the study were to compare productivity, greenhouse gas emission, and change in soil C over time and to assess whether global warming potential and global warming potential per unit biomass produced were reduced through combined mitigation strategies when implemented in the northern U.S. Corn Belt. The systems compared were (i) business as usual (BAU); (ii) maximum C sequestration (MAXC); and (iii) optimum greenhouse gas benefit (OGGB). Biomass production, greenhouse gas flux change in total and organic soil C, and global warming potential were compared among the three systems. Soil organic C accumulated only in the surface 0 to 5 cm. Three-year average emission of N?O and CH was similar among all management systems. When integrated from planting to planting, N?O emission was similar for MAXC and OGGB systems, although only MAXC was fertilized. Overall, the three systems had similar global warming potential based on 4-yr changes in soil organic C, but average rotation biomass was less in the OGGB systems. Global warming potential per dry crop yield was the least for the MAXC system and the most for OGGB system. This suggests management practices designed to reduce global warming potential can be achieved without a loss of productivity. For example, MAXC systems over time may provide sufficient soil C sequestration to offset associated greenhouse gas emission. 相似文献
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Ian C. Calder Edward J. Maynard Jane S. Heyworth 《Environmental geochemistry and health》1994,16(3-4):137-145
The Port Pirie Lead Decontamination Program commenced in 1984 with a ten year mandate. The abatement programme involves identification of children with elevated blood lead levels, house decontamination, soil treatment, general City greening, family education and support and community education. Since 1984 the smelter has also implemented substantial new environmental controls.Blood lead and air monitoring programmes as well as some investigations of recontamination are in place. The blood lead monitoring programme has shown a significant decrease in the mean blood lead levels of the children, with the magnitude of the reduction being greatest in areas remote from the smelter.The results of the air monitoring programme suggest that there has been little change in the general air lead levels in the City over the period of the abatement programme. Analysis of the data suggests that re-entrainment of lead from the contaminated areas within the City is only a small contributor to air-borne lead levels compared with that from the smelter and its environs.Sources and pathways of lead for absorption by the children in Port Pirie are discussed. 相似文献
175.
Natalie Jane Chandler Vijaya Ramachandran Clare Beesley Chineze Otigbah James Davison Tazeen Ashraf 《黑龙江环境通报》2023,43(12):1567-1569
Duo exome testing was performed on a fetus conceived via in vitro fertilization with an egg donor. The fetus presented with non-immune hydrops fetalis (NIHF) at 20 + 0 weeks gestation. Two variants were detected in the GUSB gene. Biallelic pathogenic variants cause mucopolysaccharidosis type VII (MPS-VII), which can present with NIHF prenatally. At the time of analysis and initial report, one variant was classified as likely pathogenic and the other as of uncertain clinical significance. Biochemical testing of the amniotic fluid supernatant showed elevated glycosaminoglycans and low β-glucuronidase activity consistent with the diagnosis of MPS-VII. This evidence allowed the upgrade of the pathogenicity for both variants, confirming the diagnosis of MPS-VII. The infant was born at 36 + 5 weeks and enzyme replacement therapy (ERT) using vestronidase was initiated at 20 days with planning for hematopoietic stem cell transplant ongoing. The ERT therapy has been well tolerated, with decreasing quantitative urine glycosaminoglycans. Long-term follow up is required to determine whether treatment has been successful. This case demonstrates the utility of alternative testing methods to clarify the pathogenicity of variants and the clinical utility of obtaining a diagnosis antenatally in facilitating treatment in the neonatal period, and specifically highlights MPS-VII as a treatable cause of NIHF. 相似文献
176.
Wrestling with the complexity of evaluation for organizations at the boundary of science,policy, and practice 下载免费PDF全文
R. Pitt C. Wyborn G. Page J. Hutton M. Virah Sawmy M. Ryan L. Gallagher 《Conservation biology》2018,32(5):998-1006
Boundary organizations are situated between science, policy, and practice and have a goal of supporting communication and collaboration among these sectors. They have been promoted as a way to improve the effectiveness of conservation efforts by building stronger relationships between scientists, policy makers, industry, and practitioners (Cook et al. 2013). Although their promise has been discussed in theory, the work of and expectations for boundary organizations are less defined in practice. Biodiversity conservation is characterized by complexity, uncertainty, dissent, and tight budgets, so boundary organizations face the challenging task of demonstrating their value to diverse stakeholders. We examined the challenges boundary organizations face when seeking to evaluate their work and thus aimed to encourage more productive conversations about evaluation of boundary organizations and their projects. Although no off‐the‐shelf solution is available for a given boundary organization, we identified 4 principles that will support effective evaluation for boundary organizations: engage diverse stakeholders, support learning and reflection, assess contribution to change, and align evaluation with assumption and values. 相似文献
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Gennequin Cédric Hany Sara Tidahy Haingomalala Lucette Aouad Samer Estephane Jane Aboukaïs Antoine Abi-Aad Edmond 《Environmental science and pollution research international》2016,23(22):22744-22760
Environmental Science and Pollution Research - Hydrogen production by methane dry reforming is an important yet challenging process. A performing catalyst will favor the thermodynamic equilibrium... 相似文献
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Environmental education strategies have customarily placed substantial focus on enhancing ecological knowledge and literacy with the hope that, upon discovering relevant facts and concepts, participants will be better equipped to process and dissect environmental issues and, therefore, make more informed decisions. The assumption is that informed citizens will become active citizens––enthusiastically lobbying for, and participating in, conservation‐oriented action. We surveyed and interviewed and used performance data from 432 participants in the Coastal Observation and Seabird Survey Team (COASST), a scientifically rigorous citizen science program, to explore measurable change in and links between understanding and action. We found that participation in rigorous citizen science was associated with significant increases in participant knowledge and skills; a greater connection to place and, secondarily, to community; and an increasing awareness of the relative impact of anthropogenic activities on local ecosystems specifically through increasing scientific understanding of the ecosystem and factors affecting it. Our results suggest that a place‐based, data‐rich experience linked explicitly to local, regional, and global issues can lead to measurable change in individual and collective action, expressed in our case study principally through participation in citizen science and community action and communication of program results to personal acquaintances and elected officials. We propose the following tenets of conservation literacy based on emergent themes and the connections between them explicit in our data: place‐based learning creates personal meaning making; individual experience nested within collective (i.e., program‐wide) experience facilitates an understanding of the ecosystem process and function at local and regional scales; and science‐based meaning making creates informed concern (i.e., the ability to discern both natural and anthropogenic forcing), which allows individuals to develop a personalized prioritization schema and engage in conservation action. 相似文献
180.
Spatial relationships between lead sources and children’s blood lead levels in the urban center of Indianapolis (USA) 总被引:1,自引:0,他引:1
Deborah Morrison Qing Lin Sarah Wiehe Gilbert Liu Marc Rosenman Trevor Fuller Jane Wang Gabriel Filippelli 《Environmental geochemistry and health》2013,35(2):171-183
Urban children remain disproportionately at risk of having higher blood lead levels than their suburban counterparts. The Westside Cooperative Organization (WESCO), located in Marion County, Indianapolis, Indiana, has a history of children with high blood lead levels as well as high soil lead (Pb) values. This study aims at determining the spatial relationship between soil Pb sources and children’s blood lead levels. Soils have been identified as a source of chronic Pb exposure to children, but the spatial scale of the source–recipient relationship is not well characterized. Neighborhood-wide analysis of soil Pb distribution along with a furnace filter technique for sampling interior Pb accumulation for selected homes (n = 7) in the WESCO community was performed. Blood lead levels for children aged 0–5 years during the period 1999–2008 were collected. The study population’s mean blood lead levels were higher than national averages across all ages, race, and gender. Non-Hispanic blacks and those individuals in the Wishard advantage program had the highest proportion of elevated blood lead levels. The results show that while there is not a direct relationship between soil Pb and children’s blood lead levels at a spatial scale of ~100 m, resuspension of locally sourced soil is occurring based on the interior Pb accumulation. County-wide, the largest predictor of elevated blood lead levels is the location within the urban core. Variation in soil Pb and blood lead levels on the community level is high and not predicted by housing stock age or income. Race is a strong predictor for blood lead levels in the WESCO community. 相似文献