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551.
Hance D. Smith Frank Maes Tim A. Stojanovic Rhoda C. Ballinger 《Journal of Coastal Conservation》2011,15(2):291-303
Whilst spatial planning has evolved as a tool to manage the development and use of the terrestrial environment over decades,
the development of spatial planning systems for the marine environment are in their infancy. This paper focuses on the integration
of land and marine based spatial planning systems. This is informed by a brief overview of the regional development of the
lands and seas of Europe which underlie spatial planning systems and by a discussion of respective spatial planning systems
in terms of economic sectors, land use, and sea use. The integration of spatial planning systems is then considered, followed
by evaluation of relationships between spatial planning, and the wider field of environmental management. This includes consideration
of organisational and geographical scales, technical management including legal aspects, policy, strategic planning and time
scales of decision-making. The paper identifies the significant factors which must be considered in the integration of marine
and terrestrial planning systems over the coming decades. 相似文献
552.
Michael Ensminger Rick Bergin Frank Spurlock Kean S. Goh 《Environmental monitoring and assessment》2011,175(1-4):573-587
The California??s San Joaquin River and its tributaries including Orestimba (ORC) and Del Puerto (DPC) Creeks are listed on the 2006 US EPA Clean Water Act §303(d) list for pesticide impairment. From December 2007 through June 2008, water and sediment samples were collected from both creeks in Stanislaus County to determine concentrations of organophosphorus (OP) and pyrethroid insecticides and to identify toxicity to Ceriodaphnia dubia and Hyalella azteca. OPs were detected in almost half (10 of 21) of the water samples, at concentrations from 0.005 to 0.912 ??g L???1. Diazinon was the most frequently detected OP, followed by chlorpyrifos and dimethoate. Two water samples were toxic to C. dubia; based on median lethal concentrations (LC50), chlorpyrifos was likely the cause of this toxicity. Pyrethroids were detected more frequently in sediment samples (18 detections) than in water samples (three detections). Pyrethroid concentrations in water samples ranged from 0.005 to 0.021 ??g L???1. These concentrations were well below reported C. dubia LC50s, and toxicity was not observed in laboratory bioassays. Cyfluthrin, bifenthrin, esfenvalerate, and ??-cyhalothrin were detected in sediment samples at concentrations ranging from 1.0 to 74.4 ng g???1, dry weight. At DPC, all but one sediment sample caused 100% toxicity to H. azteca. Based on estimated toxicity units (TUs), bifenthrin was likely responsible for this toxicity and ??-cyhalothrin also contributed. At ORC, survival of H. azteca was significantly reduced in four of the 11 sediment samples. However, pyrethroids were detected in only two of these samples. Based on TUs, bifenthrin and ??-cyhalothrin likely contributed to the toxicity. 相似文献
553.
Hoffmeyer F Weiss T Lehnert M Pesch B Berresheim H Henry J Raulf-Heimsoth M Broding HC Bünger J Harth V Brüning T 《Journal of environmental monitoring : JEM》2011,13(1):212-218
It was the aim of this study to evaluate the effect of different devices on the metal concentration in exhaled breath condensate (EBC) and to prove whether working conditions in different welding companies result in diverse composition of metallic elements. The influence of two collection devices (ECoScreen, ECoScreen2) on detection of metallic elements in EBC was evaluated in 24 control subjects. Properties of ECoScreen and a frequent use can alter EBC metal content due to contamination from metallic components. ECoScreen2 turned out to be favourable for metal assessment. Concentrations of iron, nickel and chromium in EBC sampled with ECoScreen2 were compared between non-exposed controls and industrial welders. Metal concentrations in EBC were higher in 36 welders recruited from three companies. Exposure to welding fumes could be demonstrated predominantly for increased iron concentrations. Concentrations of iron and nickel differed by working conditions, but chromium could not be detected in EBC. 相似文献
554.
This overview seeks to provide context and insight into the relative importance of different aspects related to global climate change for the exposure of Northern residents to organic contaminants. A key objective is to identify, from the perspective of researchers engaged in contaminant fate, transport and bioaccumulation modelling, the most useful research questions with respect to projecting the long-term trends in human exposure. Monitoring studies, modelling results, the magnitude of projected changes and simplified quantitative approaches are used to inform the discussion. Besides the influence of temperature on contaminant amplification and distribution, accumulation of organic contaminants in the Arctic is expected to be particularly sensitive to the reduction/elimination of sea-ice cover and also changes to the frequency and intensity of precipitation events (most notably for substances that are highly susceptible to precipitation scavenging). Changes to key food-web interactions, in particular the introduction of additional trophic levels, have the potential to exert a relatively high influence on contaminant exposure but the likelihood of such changes is difficult to assess. Similarly, changes in primary productivity and dynamics of organic matter in aquatic systems could be influential for very hydrophobic contaminants, but the magnitude of change that may occur is uncertain. Shifts in the amount and location of chemical use and emissions are key considerations, in particular if substances with relatively low long range transport potential are used in closer proximity to, or even within, the Arctic in the future. Temperature-dependent increases in emissions via (re)volatilization from primary and secondary sources outside the Arctic are also important in this regard. An increased frequency of boreal forest fires has relevance for compounds emitted via biomass burning and revolatilization from soil during/after burns but compound-specific analyses are limited by the availability of reliable emission factors. However, potentially more influential for human exposure than changes to the physical environment are changes in human behaviour. This includes the gradual displacement of traditional food items by imported foods from other regions, driven by prey availability and/or consumer preference, but also the possibility of increased exposure to chemicals used in packaging materials and other consumer products, driven by dietary and lifestyle choices. 相似文献
555.
Kumar A Howard CJ Derrick D Malkina IL Mitloehner FM Kleeman MJ Alaimo CP Flocchini RG Green PG 《Journal of environmental quality》2011,40(5):1423-1431
Large-scale agricultural activities have come under scrutiny for possible contributions to the emission of ozone precursors. The San Joaquin Valley (SJV) of California is an area with intense agricultural activity that exceeds the federal ozone standards for more than 30 to 40 d yr(-1) and the more stringent state standards for more than 100 d yr(-1). Pesticides are used widely in both agricultural and residential subregions of the SJV, but the largest use, by weight of "active ingredient," is in agriculture. The objective of the study was to determine the role of pesticide application on airborne volatile organic compounds (VOC) concentrations and ozone formation in the SJV. The ozone formation from the pesticide formulation sprayed on commercial orchards was studied using two transportable smog chambers at four application sites during the summers of 2007 and 2008. In addition to the direct measurements of ozone formation, airborne VOC concentrations were measured before and after pesticide spraying using canister and sorbent tube sampling techniques. Soil VOC concentrations were also measured to understand the distribution of VOCs between different environmental compartments. Numerous VOCs were detected in the air and soil samples throughout the experiment but higher molecular weight aromatic hydrocarbons were the primary compounds observed in elevated concentrations immediately after pesticide spraying. Measurements indicate that the ozone concentration formed by VOC downwind of the orchard may increase up to 15 ppb after pesticide application, with a return back to prespray levels after 1 to 2 d. 相似文献
556.
Frank A. Licari C. David Weimer 《Journal of Loss Prevention in the Process Industries》2011,24(6):736-752
Siting regulations and industrial standards for liquefied natural gas (LNG) terminals are evolving along different paths within Europe and the United States (U.S.). The 49 Code of Federal Regulations (CFR), Part 190 continues to delineate the United States process to adopt and revise safety regulations pertaining to LNG terminals and peak shaving plant sitting.1 Embodied in these regulations are rich legal and regulatory traditions that are unique to the U.S. perspective. For example, the public is encouraged to petition existing regulations and to comment on regulatory proposals. Litigation within the U.S. court system is another means by which industry and the public may seek regulatory change. This approach promotes public involvement in governmental oversight and creates a distinctive obligation and accountability for U.S. regulatory agencies, which uniquely shape technical, safety, risk mitigation, and societal risk perspectives for siting LNG terminals.European traditions shape siting regulations for LNG terminals as well. Though American siting guidance includes references to the National Fire Protection Association’s NFPA 59A and 49 CFR, Part 193, European developers also apply the guidance within EN 1473 – a risk-based case-by-case analysis directive.2, 3 and 4 The NFPA 59A standard is applied for a basis to examine property line spacing as they pertain or may relate to off-site hazard impacts. The European approach applies the assessment and suitability of code compliance and the application of accepted engineering practices. In addition the approach incorporates the application of empirical risk assessments and computational modeling to reach an understanding of risk exposures. European policies set limits on the population’s cumulative exposure to facility risks and require LNG facility developers not to exceed established risk criteria.This paper describes how the U.S. and Europe site LNG terminals, identifies key differences in their risk-based approaches, and explains why these differences exist. This discussion also examines historical precedents that have influenced regulations and approval processes for siting LNG terminals within each continent. 相似文献
557.
Max Engel Helmut Brückner Sascha Fürstenberg Peter Frenzel Anna Maria Konopczak Anja Scheffers Dieter Kelletat Simon Matthias May Frank Schäbitz Gerhard Daut 《Die Naturwissenschaften》2013,100(1):51-67
The Caribbean is highly vulnerable to coastal hazards. Based on their short recurrence intervals over the intra-American seas, high-category tropical cyclones and their associated effects of elevated storm surge, heavy wave impacts, mudslides and floods represent the most serious threat. Given the abundance of historical accounts and trigger mechanisms (strike-slip motion and oblique collision at the northern and southern Caribbean plate boundaries, submarine and coastal landslides, volcanism), tsunamis must be considered as well. This paper presents interdisciplinary multi-proxy investigations of sediment cores (grain size distribution, carbonate content, loss-on-ignition, magnetic susceptibility, microfauna, macrofauna) from Washington-Slagbaai National Park, NW Bonaire (Leeward Antilles). No historical tsunami is recorded for this island. However, an allochthonous marine layer found in all cores at Boka Bartol reveals several sedimentary criteria typically linked with tsunami deposits. Calibrated 14C data from these cores point to a palaeotsunami with a maximum age of 3,300 years. Alternative explanations for the creation of this layer, such as inland flooding during tropical cyclones, cannot entirely be ruled out, though in recent times even the strongest of these events on Bonaire did not deposit significant amounts of sediment onshore. The setting of Boka Bartol changed from an open mangrove-fringed embayment into a poly- to hyperhaline lagoon due to the establishment or closure of a barrier of coral rubble during or subsequent to the inferred event. The timing of the event is supported by further sedimentary evidence from other lagoonal and alluvial archives on Bonaire. 相似文献
558.
Giant honeybees (Apis dorsata) nest in the open and have developed a wide array of strategies for colony defence, including the Mexican wave-like shimmering behaviour. In this collective response, the colony members perform upward flipping of their abdomens in coordinated cascades across the nest surface. The time–space properties of these emergent waves are response patterns which have become of adaptive significance for repelling enemies in the visual domain. We report for the first time that the mechanical impulse patterns provoked by these social waves and measured by laser Doppler vibrometry generate vibrations at the central comb of the nest at the basic (=‘natural’) frequency of 2.156?±?0.042 Hz which is more than double the average repetition rate of the driving shimmering waves. Analysis of the Fourier spectra of the comb vibrations under quiescence and arousal conditions provoked by mass flight activity and shimmering waves gives rise to the proposal of two possible models for the compound physical system of the bee nest: According to the elastic oscillatory plate model, the comb vibrations deliver supra-threshold cues preferentially to those colony members positioned close to the comb. The mechanical pendulum model predicts that the comb vibrations are sensed by the members of the bee curtain in general, enabling mechanoreceptive signalling across the nest, also through the comb itself. The findings show that weak and stochastic forces, such as general quiescence or diffuse mass flight activity, cause a harmonic frequency spectrum of the comb, driving the comb as an elastic plate. However, shimmering waves provide sufficiently strong forces to move the nest as a mechanical pendulum. This vibratory behaviour may support the colony-intrinsic information hypothesis herein that the mechanical vibrations of the comb provoked by shimmering do have the potential to facilitate immediate communication of the momentary defensive state of the honeybee nest to the majority of its members. 相似文献
559.
Edward F. Shultz Axel Fehrenbacher Frank E. Pfefferkorn Michael R. Zinn Nicola J. Ferrier 《Journal of Manufacturing Processes》2013,15(1):25-33
In this paper a shared control strategy is presented that allows a skilled operator to identify irregularities that occur during robotic friction stir welding (FSW) and assist the robotic system in producing an appropriate response. Human operators are adept at identifying disturbances; however, the complexity of the friction stir welding process makes it difficult for the operator to respond. While examining the capabilities of shared control in friction stir welding, this paper focuses on responding to defects that are caused by a lack of workpiece material during butt welding, such as gaps. A compensation strategy is presented that combines the human operator's perceptual strengths with an automated procedure for adjustment of the process parameters (i.e. travel angle and plunge depth). Experiments comparing four control strategies are performed while welding 5083-H116 aluminum. Through our experiments we demonstrate that if the FSW control task is appropriately shared between the human operator and the computer control system, the weld quality (strength) can be improved (from 9 ksi to 31 ksi for a gap size of 2.5 mm) as compared with the nominal case in which no corrections are made. 相似文献
560.