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951.
《Marine Policy》2016
Marine protected areas (MPAs) are a global conservation and management tool to enhance the resilience of linked social-ecological systems with the aim of conserving biodiversity and providing ecosystem services for sustainable use. However, MPAs implemented worldwide include a large variety of zoning and management schemes from single to multiple-zoning and from no-take to multiple-use areas. The current IUCN categorisation of MPAs is based on management objectives which many times have a significant mismatch to regulations causing a strong uncertainty when evaluating global MPAs effectiveness. A novel global classification system for MPAs based on regulations of uses as an alternative or complementing the current IUCN system of categories is presented. Scores for uses weighted by their potential impact on biodiversity were built. Each zone within a MPA was scored and an MPA index integrates the zone scores. This system classifies MPAs as well as each MPA zone individually, is globally applicable and unambiguously discriminates the impacts of uses. 相似文献
952.
《Marine Policy》2016
The conservation of marine biological diversity has been identified as a crucial issue in need of legal regulation. The UNCLOS does not sufficiently address all issues relevant to viably conserve biological diversity. Legal developments concerning marine genetic resources, area-based management tools such as marine protected areas, environmental impact assessment and capacity building are being discussed as elements of a new implementing agreement. In particular, more precise legal rules concerning marine protected areas beyond national jurisdiction are needed to supplement the frame left by UNCLOS. As concerns the issue of access to genetic resources and the sharing of benefits the UNCLOS regime has gaps because the relevant activities had not been foreseen at the time of the convention's adoption. Divergent views exist as to whether the concept of the common heritage of mankind should be extended to genetic resources. 相似文献
953.
《Marine Policy》2016
Ecosystem-based fisheries management (EBFM) is often discussed by fisheries managers and stakeholders as a potential goal. EBFM is based on a multi-species approach, which varies significantly from the single species fisheries management (SSFM) approach currently practiced under the U.S. Magnuson-Stevens Fishery Conservation and Management Act (MSFCMA). EBFM is “holistic” and considers “all factors,” but it is impossible for management to incorporate all factors into EBFM. This study sought to improve understanding of factors contributing to or preventing progress toward EBFM implementation in the Mid-Atlantic Fishery Management Council (MAFMC) and New England Fishery Management Council (NEFMC), focusing on Council member and stakeholder beliefs, attitudes, and mutual understanding. Objectives included determining mutual understanding between MAFMC and NEFMC members and stakeholders about EBFM and identifying MAFMC and NEFMC member and stakeholder preferences for EBFM definitions, practices, and outcomes, and prioritizing which aspects of EBFM managers and stakeholders find most important. Stakeholders included commercial fishermen, recreational anglers, nongovernmental organization (NGO) leaders, and Scientific and Statistical Committee (SSC) members. Over 1000 survey responses about EBFM from council members and stakeholders in the Mid-Atlantic (MA) and New England (NE) regions were analyzed. The Coorientation Model was used to characterize understanding between the Council and fisheries-related stakeholder groups. For the MA and NE regions, most stakeholders agreed on definitions, practices, and possible outcomes for EBFM. Results suggest that most Council members and stakeholders in the MA and NE regions support a change from SSFM to EBFM at an incremental, intermediate, or complete, gradual (5–10 years) pace. The application of the Coorientation Model to EBFM and the fishery management councils provided insights into how an improved understanding of the attitudes, beliefs, and mutual comprehension of Council members and stakeholder groups could potentially facilitate the implementation of EBFM. Council members and stakeholders responded similarly to, and Council members correctly predicted stakeholder responses about, EBFM definitions, practices, and outcomes. These findings suggest that Council member and stakeholder agreement and understanding are not barriers to MAFMC and NEFMC adoption of EBFM. 相似文献
954.
文章阐述了海洋生态文明的实质,近海生态危机及成因,建设海洋生态文明的迫切性并提出建议。 相似文献
955.
956.
Understanding potential future influence of environmental, economic, and social drivers on land-use and sustainability is critical for guiding strategic decisions that can help nations adapt to change, anticipate opportunities, and cope with surprises. Using the Land-Use Trade-Offs (LUTO) model, we undertook a comprehensive, detailed, integrated, and quantitative scenario analysis of land-use and sustainability for Australia’s agricultural land from 2013–2050, under interacting global change and domestic policies, and considering key uncertainties. We assessed land use competition between multiple land-uses and assessed the sustainability of economic returns and ecosystem services at high spatial (1.1 km grid cells) and temporal (annual) resolution. We found substantial potential for land-use transition from agriculture to carbon plantings, environmental plantings, and biofuels cropping under certain scenarios, with impacts on the sustainability of economic returns and ecosystem services including food/fibre production, emissions abatement, water resource use, biodiversity services, and energy production. However, the type, magnitude, timing, and location of land-use responses and their impacts were highly dependent on scenario parameter assumptions including global outlook and emissions abatement effort, domestic land-use policy settings, land-use change adoption behaviour, productivity growth, and capacity constraints. With strong global abatement incentives complemented by biodiversity-focussed domestic land-use policy, land-use responses can substantially increase and diversify economic returns to land and produce a much wider range of ecosystem services such as emissions abatement, biodiversity, and energy, without major impacts on agricultural production. However, better governance is needed for managing potentially significant water resource impacts. The results have wide-ranging implications for land-use and sustainability policy and governance at global and domestic scales and can inform strategic thinking and decision-making about land-use and sustainability in Australia. A comprehensive and freely available 26 GB data pack (http://doi.org/10.4225/08/5604A2E8A00CC) provides a unique resource for further research. As similarly nuanced transformational change is also possible elsewhere, our template for comprehensive, integrated, quantitative, and high resolution scenario analysis can support other nations in strategic thinking and decision-making to prepare for an uncertain future. 相似文献
957.
Local regression methods such as geographically weighted regression (GWR) can provide specific information about individual locations (or places) in spatial analysis that is useful for mapping nonstationary covariate relationships. However, the distance-based weighting schemes used in GWR are only adaptable for spatial objects that are point or area features. In particular, spatial object-pairs pose a challenge for local analysis because they have a linear dimensionality rather than a point dimensionality. This paper proposes using an alternative local regression model – quantile regression (QR) – for investigating the stationarity of regression parameters with respect to these linear features as well as facilitating the visualization of the results. An empirical example of a gravity model analysis of trade patterns within Europe is used to illustrate the utility of the proposed method. 相似文献
958.
Tomàs Artés Andrés Cencerrado Ana Cortés Tomàs Margalef 《International journal of geographical information science》2016,30(3):594-611
AbstractForest fires are a kind of natural hazard with a high number of occurrences in southern European countries. To avoid major damages and to improve forest fire management, one can use forest fire spread simulators to predict fire behavior. When providing forest fire predictions, there are two main considerations: accuracy and computation time. In the context of natural hazards simulation, it is well known that part of the final forecast error comes from uncertainty in the input data. These data typically consist of a set of GIS files, which should be appropriately conflated. For this reason, several input data calibration methods have been developed by the scientific community. In this work, the Two-Stage calibration methodology, which has been shown to provide good results, is used. This calibration strategy is computationally intensive and time-consuming because it uses a Genetic Algorithm as a solution. Taking into account the aspect of urgency in forest fire spread prediction, it is necessary to maintain a balance between accuracy and the time needed to calibrate the input parameters. In order to take advantage of this technique, one must deal with the problem that some of the obtained solutions are impractical, since they involve simulation times that are too long, preventing the prediction system from being deployed at an operational level. A new method which finds the minimum resolution reduction for such long simulations, keeping accuracy loss to a known interval, is proposed. The proposed improvement is based on a time-aware core allocation policy that enables real-time forest fire spread forecasting. The final prediction system is a cyberinfrastructure, which enables forest fire spread prediction at real time. 相似文献
959.
The objective of this study is to investigate the exposure of different population groups to severe injury crash hotspots using an empirical-Gaussian two-step floating catchment area (EG-2SFCA) method based on roadway network distances and a socioeconomic-based weighting approach. This is performed by developing a special form of a crash-to-population ratio index that incorporates the severe crash hotspots relative to the locations of populations they might impact. While identifying these hotspots, four different age groups are considered: 17 and younger, 18 to 21, 22 to 64 and 65 and older. For each age group, severe crash hotspots are identified based on the roadway network and the number of severely injured crash occupants that belong to the specific age group. Using these age-specific crash hotspots and the EG-2SFCA method, communities that were exposed to elevated crash injury risk (crash injury exposure) have been identified. Furthermore, from a residential perspective, a socioeconomic analysis is conducted in order to develop a socioeconomics-based crash injury exposure measure. This measure assesses the exposure of different socioeconomic groups to the risk of being injured. Results demonstrated by applying this measure in the Tampa Bay region, FL show that different population groups are under varying risk of being injured depending on their residential location. The developed approach has the potential to be a social fairness measure able to be applied by agencies, which could enhance the well-being of communities that are subject to elevated injury risk. 相似文献
960.
A devastating flood occurred in southern Alberta on June 19, 2013, from greater than normal snowfalls in the Rocky Mountains and excess precipitation during the early spring that left soils saturated and unable to absorb any additional precipitation. This flood was Canada's most costly natural disaster, with five to six billion Canadian dollars in damages. The first objective of this study was to determine if the flood caused an increase in private drinking water well contamination in the Calgary Health Zone by comparing contamination rates to previous years. The second objective was to determine which environmental factors were associated with contamination during this flood event. Test results of total coliforms (TC) and Escherichia coli (EC) of private water wells were used to determine contamination. A geographically weighted Poisson regression analysis suggested that TC contamination was not associated with this flood. The EC contamination is positively associated with floodways, flood fringe, farms, and negatively associated with intermittent water (sloughs). These results suggest that for the 2013 flood, individual well characteristics are more important than surrounding geographic features. Thus, it is recommended that homeowners who live in a high-risk area ensure their wells are properly maintained to reduce risk of water well contamination. 相似文献