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981.
Alexandridis TK Lazaridou E Tsirika A Zalidis GC 《Journal of environmental management》2009,90(7):2243-2251
The European Habitats Directive 92/43/EEC has defined the need for the conservation of habitats and species with the adoption of appropriate measures. Within the Natura 2000 ecological network of special areas of conservation, natural habitats will be monitored to ensure the maintenance or restoration of their composition, structure and extent. The European Space Agency's GlobWetland project has provided remotely sensed products for several Ramsar wetlands worldwide, such as detailed land cover-land use, water cycle and inundated vegetation maps. This paper presents the development and testing of an operational methodology for updating a wetland's habitat map using the GlobWetland products, and the evaluation of the extent to which GlobWetland products have contributed to the habitat map updating. The developed methodology incorporated both automated and analyst-supervised techniques to photo-interpret, delineate, refine, and evaluate the updated habitat polygons. The developed methodology was proven successful in its application to the wetland complex of the Axios-Loudias-Aliakmon delta (Greece). The resulting habitat map met the European and Greek national requirements. Results revealed that GlobWetland products were a valuable contribution, but source data (enhanced satellite images) were necessary to discriminate spectrally similar habitats. Finally, the developed methodology can be modified for original habitat mapping. 相似文献
982.
Rapid growth in marine sand mining for construction and other uses poses environmental challenges to coastal nations virtually
worldwide. Yet the development of management policies, such as a system of fees imposed on operators for damage caused by
mining, has been frustrated by a lack of studies to support such measures. Adapting a Beverton-Holt bioeconomic model, this
paper attempts to contribute to the estimation of external costs to commercial fisheries due to marine mining. Using the major
mining area of Ongjin in Korea as a case study, we estimate economic losses in use value of commercial fisheries through the
time to recovery of the injured resource stocks. Present value of lost catch over a 1-year period from mining to resource
recovery is estimated at $38,851 for a single “prototype” mining site. Estimated cumulative damages due to recurring mining
for 5 and 10 years are $1.5 million and $2.2 million, respectively, at 20 mining sites. Sensitivity analyses are used to examine
the effects of alternative assumptions to assess the many sources of uncertainty. Using a form of meta-analysis, dose-response
information is used to assess the excess mortality the mining sediment plume has on eggs and larvae and, ultimately, on the
value of lost catch ($841). Also addressed is the importance of specifying the appropriate “premining” conditions against
which to assess environmental losses at the mining site. Damages estimated with premining fish populations are $23,066 higher
than is the case using postmining conditions. Overall, the illustrative results suggest the variety of complex conditions
which influence damage to fisheries from mining and which can benefit from further study to improve management guidelines.
An erratum to this article can be found at 相似文献
983.
In this article we present a framework for assessing climate change impacts on water and watershed systems to support management
decision-making. The framework addresses three issues complicating assessments of climate change impacts—linkages across spatial
scales, linkages across temporal scales, and linkages across scientific and management disciplines. A major theme underlying
the framework is that, due to current limitations in modeling capabilities, assessing and responding to climate change should
be approached from the perspective of risk assessment and management rather than as a prediction problem. The framework is
based generally on ecological risk assessment and similar approaches. A second theme underlying the framework is the need
for close collaboration among climate scientists, scientists interested in assessing impacts, and resource managers and decision
makers. A case study illustrating an application of the framework is also presented that provides a specific, practical example
of how the framework was used to assess the impacts of climate change on water quality in a mid-Atlantic, U.S., watershed. 相似文献
984.
Natalie A. Jones Pascal Perez Thomas G. Measham Gail J. Kelly Patrick d’Aquino Katherine A. Daniell Anne Dray Nils Ferrand 《Environmental management》2009,44(6):1180-1195
Participatory modeling is increasingly recognized as an effective way to assist collective decision-making processes in the
domain of natural resource management. This article introduces a framework for evaluating projects that have adopted a participatory
modeling approach. This evaluation framework—known as the “Protocol of Canberra”—was developed through a collaboration between
French and Australian researchers engaged in participatory modeling and evaluation research. The framework seeks to assess
the extent to which different participatory modeling initiatives not only modify perceptions among and interactions between
participants, but also contribute to collective decision-making. The article discusses the development of the framework and
it’s application to three case-studies, two from Australia and one from the Pacific Island of the Republic of Kiribati. The
article concludes with some comments for future use of the framework in a range of participatory modeling contexts. 相似文献
985.
A new all season passive sampling system for monitoring O3 in the atmosphere has been developed in the laboratory and validated in the field. The unique features for this system include a newly designed passive sampler and a rain shelter, which allow the passive sampler to be installed in the field facing downwards. An equation associated with meteorological parameters is used to calculate the passive sampling rates. This system has been extensively tested in the lab (temperature from –18 to 20°C, relative humidity from 13 to 81%, and wind speed from 0.5 to 150 cm/s) and validated in the field in climates of all seasons. The accuracy of the ozone concentrations in the atmosphere obtained with the use of the new passive sampling system was higher than 85% compared to those obtained with continuous ozone analyzers. The new ozone passive sampling system can be used to measure ambient O3 concentrations ranging from 3 ppb to 1000 ppb based on one-day exposure and 0.1 ppb to 140 ppb for a monthly exposure period. It is also reasonable to conclude that the new passive sampling system can be used for eight-hour exposure study because of the low field blanks and high sampling rates. 相似文献
986.
This study evaluated the spatial and temporal distribution of metals in the coral reef system Cayos Arcas and Triangulos in the Campeche Bank region, off the Yucatan peninsula in Mexico. No information has been generated before for the incorporation of natural and non-natural occurring metals, some of which are possibly endowed by the oil marine station Cayo Arcas. The multivariate exploratory study of the metals on the coral skeletons, showed the formation of two distinct groups. The metals that have the highest influence on the differentiation of the groups are the metals that are natural constituents of the coral skeletons, in particular Sr can explain much of the differences between the groups, and to a much lesser extent are the metals that could be indicators of pollution. This differentiation suggests that, in our case, the environment around the corals has a higher impact than the non-naturally occurring metals (and possible indicators of pollution). The two groups formed corresponded to: the coral cores influenced by open sea variables and the coral cores in the inner part of the keys which is less exposed to open sea variables. A chronological study was made to two samples that had the longest coral section and were situated in two clearly distinctive zones: an exposed surface subjected to high wave forces and another that was less exposed. Ni and Zn show an accumulation trend in both coral samples, while Ba showed an increase in incorporation around 1980 when the Cayo Arcas oil marine station was constructed. 相似文献
987.
The current study utilizes social identity theory to investigate employees' work hours. Specifically, we use meta‐analysis to examine the relationships between hours worked and indicators of organizational identity (e.g., organizational support and tenure), occupational identity (e.g., human capital investments and work centrality), and family identity (e.g., family responsibilities and family satisfaction). The meta‐analysis also allowed us to explore other important correlates of hours worked (e.g., situational demands, job performance, mental health, and physical health), moderating variables (e.g., age, gender, and job complexity), and curvilinear relationships of work hours to social identity indicators. Overall, we found that occupational factors and situational demands had the strongest relationships with hours worked, hours worked were negatively associated with measures of employee well‐being, gender had several significant moderating effects, and there were curvilinear relationships between hours worked and well‐being and work–family conflict variables. The article concludes with directions for future theoretical and empirical research. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
988.
In recent years there has been continuing interest in the potential hazards from detonations in pipelines. The interest has arisen in several instances due to the introduction of vapour recover systems, as part of measures to limit environmental emissions. These environmental pressures initially coincided with the preparation of new European-wide test procedures for explosion arrester devices and, more recently, moves to develop a new international ISO standard for the certification and approval of detonation arrester devices. It is an opportune time therefore to review current understanding of explosion development in pipelines and to consider the implications for plant design and explosion arrester selection and testing. 相似文献
989.
990.
Lind BB Norrman J Larsson LB Ohlsson SA Bristav H 《Waste management (New York, N.Y.)》2008,28(1):170-180
A study was performed between June 2001 and December 2004 with the primary objective of assessing long-term leaching from municipal solid waste incineration bottom ash in a test road construction in relation to a reference road made up of conventional materials and the natural geochemical conditions in the surroundings. The metal leaching from the test road and the reference road was compared with the natural weathering in the regional surroundings for three time scales: 16, 80 and 1000 years. The results show that Cu and Zn cause a geochemical anomaly from the test road compared with the surroundings. The leaching of Cu from the test road is initially high but will decline with time and will in the long term be exceeded by natural weathering. Zn on the other hand has low initial leaching, which will increase with time and will in the long term exceed that of the test road and the surroundings by a factor of 100-300. For the other metals studied, Al, Na, K and Mg, there is only very limited leaching over time and the potential accumulation will not exceed the background values in a 1000 years. 相似文献