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911.
The feasibility of reducing children's exposure to lead (Pb) polluted soil in New Orleans is tested. Childcare centers (median = 48 children) are often located in former residences. The extent of soil Pb was determined by selecting centers in both the core and outlying areas. The initial 558 mg/kg median soil Pb (range 14-3692 mg/kg) decreased to median 4.1 mg/kg (range 2.2-26.1 mg/kg) after intervention with geotextile covered by 15 cm of river alluvium. Pb loading decreased from a median of 4887 μg/m(2) (454 μg/ft(2)) range 603-56650 μg/m(2) (56-5263 μg/ft(2)) to a median of 398 μg/m(2) (37 μg/ft(2)) range 86-980 μg/m(2) (8-91 μg/ft(2)). Multi-Response Permutation Procedures indicate similar (P-values = 0.160-0.231) soil Pb at childcare centers compared to soil Pb of nearby residential communities. At ~$100 per child, soil Pb and surface loading were reduced within hours, advancing an upstream intervention conceptualization about Pb exposure prevention.  相似文献   
912.
新的斯德哥尔摩可持续城市伙伴关系论坛,通过城市和企业间的伙伴关系,将推动可持续性融入城市规划的进程.开始于2000年秋季的这个论坛,标志着1972年联合国环境大会已届30周年.全欧各城市的决策者及其选定的企业界同行将应邀参加.论坛将举办的活动包括各种专题研讨会和在线讨论会.  相似文献   
913.
Environmental Science and Pollution Research - The main aim of this current study is to empirically scrutinize the determinants of energy consumption for 24 African countries sub-grouped into three...  相似文献   
914.
One of the traditional livelihood practices of indigenous Tagbanuas in Palawan, Philippines is wild honey hunting and gathering from the giant honey bee (Apis dorsata F.). In order to analyze the linkages of the social and ecological systems involved in this indigenous practice, we conducted spatial, quantitative, and qualitative analyses on field data gathered through mapping of global positioning system coordinates, community surveys, and key informant interviews. We found that only 24% of the 251 local community members surveyed could correctly identify the giant honey bee. Inferential statistics showed that a lower level of formal education strongly correlates with correct identification of the giant honey bee. Spatial analysis revealed that mean NDVI of sampled nesting tree areas has dropped from 0.61 in the year 1988 to 0.41 in 2015. However, those who correctly identified the giant honey bee lived in areas with high vegetation cover. Decreasing vegetation cover limits the presence of wild honey bees and this may also be limiting direct experience of the community with wild honey bees. However, with causality yet to be established, we recommend conducting further studies to concretely model feedbacks between ecological changes and local knowledge.  相似文献   
915.
A developed instantaneous emission model is applied to predict emission factors for small vehicle fleets for quality assessment. Extensive vehicle measurements of pre-Euro-1 gasoline, Euro-3 gasoline, and Euro-2 diesel vehicles are available. The data were used to develop individual vehicle emission models for each car. The prediction quality for each vehicle category was determined by averaging the results obtained from the individual vehicle models. The results show that the prediction quality is improved in comparison with the individual vehicles, even with a small number of vehicles in a specific category. This indicates that the errors in the individual models are mainly random and that prediction quality, when applied to fleets of cars, is exceptionally high.  相似文献   
916.
Agricultural NH3 emissions affect air quality and influence the nitrogen cycle. In the subject study, NH3 emissions from a broiler farm and the resulting atmospheric concentrations in the immediate vicinity during three growing cycles have been quantified. Additionally, vegetation along a transect in an adjacent woodland was analysed. The emissions were as high as 10 kg NH3 h−1 and the atmospheric concentrations ranged between 33 and 124 μg NH3 m−3 per week in the immediate vicinity. Measurements of the atmospheric concentrations over 7 weeks showed a substantial decline of mean concentrations (based on a 3-week average) from ∼13 to <3 μg NH3 m−3, at 45- and 415-m distance from the farm. Vegetation surveys showed that nitrophilous species flourished when they grew closest to the farm (their occurrence sank proportionately with distance). A clearly visible damage of pine trees was observed within 200 m of the farm; this illustrated the significant impact of NH3 emissions from agricultural sources on the sensitive ecosystem.  相似文献   
917.
A subjective visual assessment of foliage density is the mostwidely used rapid method of determining forest health. Forthese assessments to be ecologically meaningful they must bereliable (have low inter- and intra-observer variability) andreadily relate to a measure of physiological or physicalstress. A simple rapid method for assessing percent foliagedensity in lower stature trees is described. This method haslow inter-observer variability (standard deviation betweenobservers=8.6%) and therefore, minimizes the risk ofconfounding the effects of different observers with genuinechanges in density. The percentage changes in this measure offoliage density correlate well with percentage changes inbiomass, allowing a ready interpretation of observed changes.The technique does not specifically identify the cause of themeasured changes, however, with appropriate additionalmeasures this problem may be overcome.  相似文献   
918.
919.
The Scottish Raptor Monitoring Scheme (SRMS) comprises 7 partner organizations and was established in 2002 after i) the publication of the UK Government's Raptor Working Group Report that made recommendations for enhanced monitoring, ii) increased applied data needs (e.g., for site designation), and iii) concerns for the status of some species. The SRMS has 3 major objectives: i) to facilitate cooperation between parties; ii) to provide robust information on Scottish raptor populations by determining trends in numbers, range, survival, and productivity and understanding the causes of change; and iii) to maintain high and uniform standards for the collection, collation, auditing, and analysis of data and reporting of information. Data are collected for 19 species: 14 diurnal raptors, 4 owls, and 1 corvid, the Common Raven. Here we describe the development of the scheme, challenges, and achievements during its first 4 y, the nature and value of the data collected, and plans for the future.  相似文献   
920.
Mielke HW  Gonzales C 《Chemosphere》2008,72(6):882-885
Pre-1992, latex paint was formulated with mercury (Hg) as phenylmercuric acetate (PMA). Hg vaporizes reducing its content, and lead (Pb) is stable and remains unchanged. The objective of this study is to describe the content of Hg and Pb in existing paint coatings. Forty paint chip samples were collected from both interior and exterior surfaces of homes in metropolitan New Orleans and analyzed for Hg and Pb. The median Hg in exterior paints is 26.9 mg kg(-1) (0.8-214.0) compared with 7.1 mg kg(-1) (0.03-39.2) for interior paints. The median Pb content is 76603 mg kg(-1) (464-317151) and 416 mg kg(-1) (24-63313) respectively, for exterior and interior paints. The Spearman correlation coefficients for Hg and Pb are -0.312 (P=0.13) and -0.471 (P=0.07) respectively, in exterior and interior samples. Hg and Pb vary independently with each other in paint films. Median Hg in exterior paints is four times larger than for interior paints. Median Pb in exterior paints is 184 times larger than interior paints. The Pb and Hg content in exterior and interior paint chips are significantly different (Mann-Whitney Rank Sum Test, P0.001 and P=0.006, respectively). Only 1 of the 25 exterior paints contained less than the current 5000 mg kg(-1) US standard for Pb, the criteria for exemption from the power-sanding restrictions of the New Orleans Lead Ordinance. Prior to banning PMA in paint, Hg poisonings presented as acrodynia were reported for children living in homes freshly painted with latex paint. Because of the affinity of Hg and Pb for sulfur-containing amino acid proteins, their presence in paint coatings poses an increased hazard when released as dust.  相似文献   
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