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301.
Like many other states in the USA, Virginia passed legislation to protect coastal wetlands with limited information on the rate and location of past wetlands conversions. This information, however, can be useful in the design of cost-effective and flexible programs for wetlands management, particularly when such information is used in combination with studies of the socioeconomic value of wetlands. This paper reports on the use of photogrammetric and interpretive methods to determine historical changes in wetlands use for Virginia Beach and Accomack counties, Virginia. Conclusions are drawn as to the use of such information in policy design and program monitoring.  相似文献   
302.
This paper comments on the slow and uneven occupational development of safety specialists in British industry. It provides an analysis of possible strategies for safety specialists by identifying three main areas of activity: processing and generating information, giving advice and participating in problem-solving, and taking direct action. These may be practised at each of the following five stages involved in the technical control of hazards: identification of hazards, assessment of risk, development of controls, implementation of controls and longer-term monitoring and adaptation. Hie position of specialists encountered in eight case studies in the chemical and related industries is then described. The third section advocates the role of the specialist as adviser and discusses the importance of line management assuming direct executive responsibility for the health and safety of those for whom they are directly responsible. The paper acknowledges some of the obstacles facing specialists who wish to develop a strong advisory and problem-solving function. It considers the specialists' access to the following sources of power and influence: managerial dependence on their expertise, patronage within the hierarchy, a direct controlling function, internal coalitions formed with representatives of the workforce, external coalition formed with the factory inspectorate, formal organizational position and their personal qualities of charm and leadership. Comments are made on how aspects of the organizational context and climate of opinion affect the specialists' access to these power sources and the final section of the paper considers the effect of different recruitment and career paths of the specialists themselves.  相似文献   
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304.
The problem of assessing the sustainability of human development is discussed in theoretical and practical terms.In Part I, two theoretical tools for describing the challenge of assessing sustainable development are introduced and briefly discussed: (i) the use of an energetic model to describe the dynamic interaction between the human and the biophysical compartment; (ii) basic concepts derived from the hierarchy theory applied to the development of human society. Sustainable and ethical development of human society requires the consideration of three hierarchical levels: the biosphere, the societal and the individual level. Such a holistic assessment can be obtained by integrating scientific and ethical considerations.In Part II, data illustrating the current terms of the dilemma of human development are presented and discussed within the theoretical frame provided in Part I. It is argued that even if we had a better understanding of the consequeces of human activity on the biosphere, current modes of organization of human society and its economic activity do not readily enable adequate planning for the sustainable development of mankind. Ideologies that can bias the discussion and the assessment of sustainable and ethical development are discussed. No solution is at hand; therefore, when we consider human development today, we are facing a high level of uncertainty.  相似文献   
305.
The effect of arbuscular mycorrhiza on heavy metal uptake and translocation was investigated in Cannabis sativa. Hemp was grown in the presence and absence of 100 microg g-1 Cd and Ni and 300 microg g-1 Cr(VI), and inoculated or not with the arbuscular mycorrhizal fungus Glomus mosseae. In our experimental condition, hemp growth was reduced in inoculated plants and the reduction was related to the degree of mycorrhization. The percentage of mycorrhizal colonisation was 42% and 9% in plants grown in non-contaminated and contaminated soil, suggesting a significant negative effect of high metal concentrations on plant infection by G. mosseae. Soil pH, metal bioavailability and plant metal uptake were not influenced by mycorrhization. The organ metal concentrations were not statistically different between inoculated and non-inoculated plants, apart from Ni which concentration was significantly higher in stem and leaf of inoculated plants grown in contaminated soil. The distribution of absorbed metals inside plant was related to the soil heavy metal concentrations: in plant grown in non-contaminated soil the greater part of absorbed Cr and Ni was found in shoots and no significant difference was determined between inoculated and non-inoculated plants. On the contrary, plants grown in artificially contaminated soil accumulated most metal in root organ. In this soil, mycorrhization significantly enhanced the translocation of all the three metals from root to shoot. The possibility to increase metal accumulation in shoot is very interesting for phytoextraction purpose, since most high producing biomass plants, such as non-mycorrhized hemp, retain most heavy metals in roots, limiting their application.  相似文献   
306.
In the terrestrial environment, standardized protocols are available for measuring the exposure and effects of contaminants to invertebrates, but none currently exist for vertebrates. In an effort to address this, we proposed that developing lizard embryos may be used as a terrestrial vertebrate model. Lizard eggs may be particularly susceptible to soil contamination and in ovo exposure may affect hatchling size, mortality, as well as thyroid function. Toxicant-induced perturbations of thyroid function resulting from in ovo chemical exposure may result in toxicity during the critical perinatal period in reptiles. Fertilized Eastern fence lizard (Sceloporus undulatus) eggs were placed in cadmium (Cd)-spiked expanded perlite (0, 1.48, 14.8, 148, 1480, 14 800 μg Cd/g, nominal concentrations), artificially incubated at 28 °C, and examined daily for mortality. Whole lizard hatchlings as well as failed hatches were homogenized in ethanol and the homogenate was divided for Cd body residue analysis and thyroid hormone (triiodothyronine (T3) and thyroxine (T4)) analyses. Acute mortality was observed in the two highest doses (1480 and 14 800 μg Cd/g). Cadmium body residues showed a higher internal concentration with increasing exposure concentration indicating uptake of Cd. There was a decrease in T3:T4 ratio at the highest surviving dose (148 μg Cd/g), however, there were no differences observed in hatchling size measured as weight and snout-vent length, or in whole body thyroid hormone levels. In summary, this study has shown Cd amended to a solid phase representing soil (perlite) can traverse the thin, parchment-like shell membrane of the fence lizard egg and bioaccumulate in lizard embryos. We believe this study is a good first step in investigating and evaluating this species for use as a model.  相似文献   
307.
One of the major limitations in advancing the understanding of tropospheric ozone and aerosol generation and developing strategies for their control is the technical ability to accurately measure volatile organic compounds (VOCs). This paper describes the design of a constant flow VOC sampler. The versatile sampler can be used for fully automated concentration and flux measurements of VOCs. The sampler incorporates a microprocessor control unit and provides highly accurate mass flow control and significant ease of operation. Sampling sequences can be programmed directly or by remote control through a PC. All important operational parameters necessary for a complete sampling audit trail are logged. Compact weatherproof housings and low power consumption allow operation at remote sites and locations which are sensitive to disturbances or have restricted access. Inner wetted surfaces of the sampler are constructed from non-contaminating materials that do not sorb or emit VOC, and thus permit the collection of representative samples even in environments with very low VOC concentrations. The cartridge magazine provides a maximum of 20 sequential cartridge samples, which allows for long-term air quality assessments. In the dual channel mode, two samples can be collected simultaneously through two independent sample loops, providing ten sequential sample pairs. This design allows the parallel collection of (a) quality assurance backup samples, (b) samples on two different types of cartridges/sorbents to allow a variety of analyses, or (c) differential samples for flux measurements using enclosure, aerodynamic profile, or relaxed eddy accumulation (REA) methods. Field applications including airplane profile measurements above a tropical rainforest area, as well as gradient and REA measurements over a mid-latitude mixed forest stand are described, and demonstrate the validity and flexibility of the system. In particular, the application of the VOC sampler as an integrated part of a REA system is emphasized.  相似文献   
308.
309.
Researchers have claimed that routinization hinders creativity. However, empirical evidence for this assumption is sparse. In this study, we argue that routinization may be beneficial for creativity and related behavior due to available resources that can be used to develop new ideas while working. We examine the relationship between routinization and four work characteristics (job control, job complexity, time pressure, and supervisor support) on the one hand and a range of creative and proactive behaviors on the other hand in a randomly selected sample of 278 employees of a German high‐tech company. Regression analyses reveal that in addition to work characteristics, routinization is generally positively related to creative and proactive behaviors. Ways to enhance routinization and thereby creative and proactive behaviors are discussed. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
310.
Climate change is occurring with greater speed and intensity that previously anticipated. All effective environmentally and socially sound mitigation efforts need to be employed to effectively address this global crisis. Land Use, Land Use Change and Forestry (LULUCF) projects can provide significant climate change mitigation benefits as well as poverty alleviation and biodiversity conservation benefits. The policies of the European Union Emissions Trading Scheme (EU-ETS), the world’s largest carbon market exclude LULUCF. Scientific support for this exclusion was presented in a briefing paper published by the Climate Action Network—Europe (CAN) that puts forward the proposition that land based storage of carbon is ineffective. A careful review of the scientific papers cited in support of CAN’s position indicates that, while the papers themselves are scientifically sound, they do not support the continued exclusion of LULUCF projects from the EU-ETS. At the same time some important recent research papers that describe the carbon storage and social benefit potential of such projects are not included in the analysis. An in-depth consideration of the scientific evidence is necessary in evaluating this policy option. Based on this evidence a case can be made for the inclusion of LULUCF projects in the EU-ETS.  相似文献   
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