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391.
The long-term ecological recovery of an impaired stream in response to an industrial facility’s pollution abatement actions
and the implications of the biological monitoring effort to environmental management is the subject of this special issue
of Environmental Management. This final article focuses on the synthesis of the biological monitoring program’s components and methods, the efficacy
of various biological monitoring techniques to environmental management, and the lessons learned from the program that might
be applicable to the design and application of other programs. The focus of the 25-year program has been on East Fork Poplar
Creek, an ecologically impaired stream in Oak Ridge, Tennessee with varied and complex stressors from a Department of Energy
facility in its headwaters. Major components of the long-term program included testing and monitoring of invertebrate and
fish toxicity, bioindicators of fish health, fish contaminant accumulation, and instream communities (including periphyton,
benthic macroinvertebrate, and fish). Key parallel components of the program include water chemistry sampling and data management.
Multiple lines of evidence suggested positive ecological responses during three major pollution abatement periods. Based on
this case study and the related literature, effective environmental management of impaired streams starts with program design
that is consistent across space and time, but also adaptable to changing conditions. The biological monitoring approaches
used for the program provided a strong basis for assessments of recovery from remedial actions, and the likely causes of impairment.
This case study provides a unique application of multidisciplinary and quantitative techniques to address multiple and complex
regulatory and programmatic goals, environmental stressors, and remedial actions. 相似文献
392.
Personality and teamwork behavior in context: The cross‐level moderating role of collective efficacy
This research examines whether the relationship between an individual's personality and their behavior within a team is contingent on the team's overall perception of its capability. Individuals were peer‐rated on the extent to which they displayed interpersonal and performance management teamwork behaviors over the course of an 8 week business simulation. The personality trait of agreeableness predicted interpersonal teamwork behavior, while the personality traits of conscientiousness and core self‐evaluation (CSE) predicted performance management behavior. Multilevel analysis showed that collective efficacy influenced the extent to which an individual engaged in both types of behavior, and was also a cross‐level moderator of the relationship between agreeableness and interpersonal behavior and the relationship between CSE and performance management behavior. At the team level, interpersonal behavior mediated between collective efficacy and team performance. The study's results show that in team settings the personality and individual behavior relationship may depend on group level confidence perceptions. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
393.
Michael J. Liles Markus J. Peterson Yvonna S. Lincoln Jeffrey A. Seminoff Alexander R. Gaos Tarla Rai Peterson 《Local Environment》2015,20(11):1383-1404
Hawksbill turtles (Eretmochelys imbricata) are highly endangered in the eastern Pacific Ocean, yet their eggs continue to be an important subsistence resource for impoverished coastal residents in El Salvador. In this study, we use naturalistic inquiry to explain the realities experienced by coastal residents who share habitat with hawksbills in El Salvador, and then suggest implications of the disparities between these realities and international priorities for hawksbill conservation and community development in El Salvador and other low-income regions. To provide a context for understanding hawksbill conservation and its implications for similar challenges related to conservation and wellbeing, we first summarise the conservation context, including the emergence of sea turtle conservation in El Salvador. We then describe our naturalistic approach, including the ethnographic methodology for this study. Finally, we detail the analysis of interviews conducted with tortugueros (i.e. local sea turtle egg collectors), to help explain how hawksbills fit into local realities. Our results demonstrate that, from the perspective of tortugueros, (1) the primary importance of hawksbills is the economic value attached to egg sales, but there exists a deeper connection to local culture; (2) egg purchase by hatcheries is a socially just conservation strategy that benefits both hawksbill and human wellbeing; and (3) opportunities for local residents to participate in decision-making regarding sea turtle conservation are limited, and should be increased. We argue that harmonising international conservation priorities with local community development realities is one path towards simultaneously contributing to long-term sea turtle recovery and human wellbeing in low-income regions. 相似文献
394.
Richard E. Peterson Bonnie J. Tyler 《Atmospheric environment (Oxford, England : 1994)》2002,36(39-40)
This work explores the utility of time-of-flight static secondary-ion mass spectrometry (TOF-SIMS) for the analysis of the surface organic layer on individual atmospheric aerosol particles. The surface sensitivity and minimal fragmentation available with TOF-SIMS suggest that it can be a powerful tool for the examination of the organic and inorganic species on the surface of individual particles. Cascade impactors were used to collect aerosol from summer 2000 Montana forest fires, winter snowmobile samples in Yellowstone National Park, Hawaiian lava and sea salt, from an Asian Dust event reaching Salt Lake City, Utah in April 2001 and from Salt Lake Valley summer urban aerosol. TOF-SIMS analysis and multivariate statistical techniques combined gave chemical and morphological information about the particles. Surfaces of the aerosol from forest fires, snowmobile exhaust, and sea salt were all dominated by aliphatic hydrocarbons and their amphiphilic derivatives. Each source showed a different organic chemical signature. The extent and composition of the organics layer which typically covers the surface of atmospheric particles are expected to effect all of the surface related aerosol properties such as health effects, the ability of the particle to activate and form cloud droplets, and the aggregation of particles as well as reactions between the particle and gas phase species. 相似文献
395.
US policies for securing the border with Mexico are driven by multiple political concerns, including the desire to control illegal trade and immigration in a way that conveys “border security” to a national audience. Highly visible border enforcement near urban centres and via the border fence has pushed migrants into far less visible and remote wilderness areas, driving both ecological degradation and a humanitarian crisis. This study employed ethnographic methods to explore how natural resource agency employees and humanitarian volunteers in Altar Valley Arizona perceived and responded to the production of border security. We found that both groups recognised human rights and environmental concerns, although they assigned different priorities and addressed them through conflicting means. As in other cases where consumers are separated from production practices, there was a general consensus among informants that it was important to raise the consciousness of the national audience about the negative externalities of producing border security. 相似文献
396.
Excessive production of methane has been observed at some remediation sites following the addition of organic hydrogen donors such as (emulsified) oils/lecithin, sugars, and conventional carbon + zero‐valent iron (ZVI) amendments. This is due to the fact that methanogens are commonly the most ubiquitous indigenous microbes in anoxic aquifer settings, and, under enriched environmental conditions, methanogens replicate every one to two hours (whereas Dehalococcoides spp., e.g., double in 24–48 hr). Hence, methanogens often bloom and dominate the microbial ecosystem following the addition of remedial amendments, thereby liberating large amounts of methane gas. There are at least three important consequences of this response:
- By utilizing hydrogen, the methanogens compete with dechlorinating microbes, thus making inefficient use of the remedial amendment (just 20 ppm methane in groundwater represents an approximate 30 percent “waste” of added fermentable substrate (i.e., hydrogen donor)—this is a common and tangible detriment);
- Methanogens can methylate heavy metals and their rapid growth consumes alkalinity, while generating acidity, thereby facilitating multiple potential mechanisms for creating secondary contaminant issues (i.e., arsenic plumes); and
- Elevated methane concentrations can exceed current and pending regulations of <10 to <28 ppm methane in groundwater and/or 0.5 percent by volume methane in soil gas (e.g., 10 percent of the lower explosive limit) and/or indoor air (methane is flammable between 5 percent and 15 percent by volume) and this will induce migration of contaminant vapors potentially causing indoor air issues.
397.
Greg Shaw David Lessley Joseph Ash Jerry Poplin Tim McMurry Mark Sochor 《Traffic injury prevention》2017,18(1):77-82
Objectives: The 2 objectives of this study are to (1) examine the rib and sternal fractures sustained by small stature elderly females in simulated frontal crashes and (2) determine how the findings are characterized by prior knowledge and field data.Methods: A test series was conducted to evaluate the response of 5 elderly (average age 76 years) female postmortem human subjects (PMHS), similar in mass and size to a 5th percentile female, in 30 km/h frontal sled tests. The subjects were restrained on a rigid planar seat by bilateral rigid knee bolsters, pelvic blocks, and a custom force-limited 3-point shoulder and lap belt. Posttest subject injury assessment included identifying rib cage fractures by means of a radiologist read of a posttest computed tomography (CT) and an autopsy. The data from a motion capture camera system were processed to provide chest deflection, defined as the movement of the sternum relative to the spine at the level of T8.?A complementary field data investigation involved querying the NASS-CDS database over the years 1997–2012. The targeted cases involved belted front seat small female passenger vehicle occupants over 40 years old who were injured in 25 to 35 km/h delta-V frontal crashes (11 to 1 o'clock).Results: Peak upper shoulder belt tension averaged 1,970 N (SD = 140 N) in the sled tests. For all subjects, the peak x-axis deflection was recorded at the sternum with an average of ?44.5 mm or 25% of chest depth. The thoracic injury severity based on the number and distribution of rib fractures yielded 4 subjects coded as Abbreviated Injury Scale (AIS) 3 (serious) and one as AIS 5 (critical). The NASS-CDS field data investigation of small females identified 205 occupants who met the search criteria. Rib fractures were reported for 2.7% of the female occupants.Conclusions: The small elderly test subjects sustained a higher number of rib cage fractures than expected in what was intended to be a minimally injurious frontal crash test condition. Neither field studies nor prior laboratory frontal sled tests conducted with 50th percentile male PMHS predicted the injury severity observed. Although this was a limited study, the results justify further exploration of the risk of rib cage injury for small elderly female occupants. 相似文献
398.
Isotope tracing of submarine groundwater discharge offshore Ubatuba, Brazil: results of the IAEA-UNESCO SGD project 总被引:1,自引:0,他引:1
Povinec PP Bokuniewicz H Burnett WC Cable J Charette M Comanducci JF Kontar EA Moore WS Oberdorfer JA de Oliveira J Peterson R Stieglitz T Taniguchi M 《Journal of environmental radioactivity》2008,99(10):1596-1610
Results of groundwater and seawater analyses for radioactive ((3)H, (222)Rn, (223)Ra, (224)Ra, (226)Ra, and (228)Ra) and stable (D and (18)O) isotopes are presented together with in situ spatial mapping and time series (222)Rn measurements in seawater, direct seepage measurements using manual and automated seepage meters, pore water investigations using different tracers and piezometric techniques, and geoelectric surveys probing the coast. This study represents first time that such a new complex arsenal of radioactive and non-radioactive tracer techniques and geophysical methods have been used for simultaneous submarine groundwater discharge (SGD) investigations. Large fluctuations of SGD fluxes were observed at sites situated only a few meters apart (from 0cmd(-1) to 360cmd(-1); the unit represents cm(3)/cm(2)/day), as well as during a few hours (from 0cmd(-1) to 110cmd(-1)), strongly depending on the tidal fluctuations. The average SGD flux estimated from continuous (222)Rn measurements is 17+/-10cmd(-1). Integrated coastal SGD flux estimated for the Ubatuba coast using radium isotopes is about 7x10(3)m(3)d(-1) per km of the coast. The isotopic composition (deltaD and delta(18)O) of submarine waters was characterised by significant variability and heavy isotope enrichment, indicating that the contribution of groundwater in submarine waters varied from a small percentage to 20%. However, this contribution with increasing offshore distance became negligible. Automated seepage meters and time series measurements of (222)Rn activity concentration showed a negative correlation between the SGD rates and tidal stage. This is likely caused by sea level changes as tidal effects induce variations of hydraulic gradients. The geoelectric probing and piezometric measurements contributed to better understanding of the spatial distribution of different water masses present along the coast. The radium isotope data showed scattered distributions with offshore distance, which imply that seawater in a complex coast with many small bays and islands was influenced by local currents and groundwater/seawater mixing. This has also been confirmed by a relatively short residence time of 1-2 weeks for water within 25km offshore, as obtained by short-lived radium isotopes. The irregular distribution of SGD seen at Ubatuba is a characteristic of fractured rock aquifers, fed by coastal groundwater and recirculated seawater with small admixtures of groundwater, which is of potential environmental concern and has implications on the management of freshwater resources in the region. 相似文献
399.
400.
The various chemical forms of 74As accumulated from either water or food by the marine food chain [Fucus spiralis (L.) Littorina littoralis (L.)Nucella lapillus] have been separated and characterized. Arsenic components were separated by differential extraction followed by high-voltage paper electrophoresis/paper chromatography of the water-soluble fraction and thin-layer chromatography of the lipid-soluble fraction. The algae assimilates arsenic mainly (60%) as one lipid-soluble compound with Rf=0.18, and 12 water-soluble organo-arsenic compounds as minor components. On the other hand, the snails, whether labelled from water or food, produce predominantly one major water-soluble organo-arsenic compound with Rf=0.66. This water-soluble arsenic compound was produced by the snails and not by intestinal microbes. Time-course studies on the relative proportions of labelled arsenic compounds in algal tissue indicate a transition from arsenate through water-soluble organo-arsenic components to a lipid-soluble arsenic compound. The water-soluble organo-arsenic compounds in the food chain studied were different from those previously found or proposed in marine organisms. 相似文献