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171.
Towards an inter-disciplinary research agenda on climate change, water and security in Southern Europe and neighboring countries 总被引:1,自引:0,他引:1
Ralf Ludwig Roberto Roson Christos Zografos Giorgios Kallis 《Environmental Science & Policy》2011,14(7):794-803
The Mediterranean and neighboring countries are already experiencing a broad range of natural and man-made threats to water security. According to climate projections, the region is at risk due to its pronounced susceptibility to changes in the hydrological budget and extremes. Such changes are expected to have strong impacts on the management of water resources and on key strategic sectors of regional economies. Related developments have an increased capacity to exacerbate tensions, and even intra- and inter-state conflict among social, political, ecological and economic actors. Thus, effective adaptation and prevention policy measures call for multi-disciplinary analysis and action.This review paper presents the current state-of-the-art on research related to climate change impacts upon water resources and security from an ecological, economic and social angle. It provides perspectives for current and upcoming research needs and describes the challenges and potential of integrating and clustering multi-disciplinary research interests in complex and interwoven human-environment systems and its contribution to the upcoming 5th assessment report of the IPCC. 相似文献
172.
Nestor E. Bosch Jacquomo Monk Jordan Goetze Shaun Wilson Russell C. Babcock Neville Barrett Jock Clough Leanne M. Currey-Randall David V. Fairclough Rebecca Fisher Brooke A. Gibbons David Harasti Euan S. Harvey Michelle R. Heupel Jamie L. Hicks Thomas H. Holmes Charlie Huveneers Daniel Ierodiaconou Alan Jordan Nathan A. Knott Hamish A. Malcolm Dianne McLean Mark Meekan Stephen J. Newman Ben Radford Matthew J. Rees Benjamin J. Saunders Conrad W. Speed Michael J. Travers Corey B. Wakefield Thomas Wernberg Tim J. Langlois 《Conservation biology》2022,36(2):e13807
Marine fisheries in coastal ecosystems in many areas of the world have historically removed large-bodied individuals, potentially impairing ecosystem functioning and the long-term sustainability of fish populations. Reporting on size-based indicators that link to food-web structure can contribute to ecosystem-based management, but the application of these indicators over large (cross-ecosystem) geographical scales has been limited to either fisheries-dependent catch data or diver-based methods restricted to shallow waters (<20 m) that can misrepresent the abundance of large-bodied fished species. We obtained data on the body-size structure of 82 recreationally or commercially targeted marine demersal teleosts from 2904 deployments of baited remote underwater stereo-video (stereo-BRUV). Sampling was at up to 50 m depth and covered approximately 10,000 km of the continental shelf of Australia. Seascape relief, water depth, and human gravity (i.e., a proxy of human impacts) were the strongest predictors of the probability of occurrence of large fishes and the abundance of fishes above the minimum legal size of capture. No-take marine reserves had a positive effect on the abundance of fishes above legal size, although the effect varied across species groups. In contrast, sublegal fishes were best predicted by gradients in sea surface temperature (mean and variance). In areas of low human impact, large fishes were about three times more likely to be encountered and fishes of legal size were approximately five times more abundant. For conspicuous species groups with contrasting habitat, environmental, and biogeographic affinities, abundance of legal-size fishes typically declined as human impact increased. Our large-scale quantitative analyses highlight the combined importance of seascape complexity, regions with low human footprint, and no-take marine reserves in protecting large-bodied fishes across a broad range of species and ecosystem configurations. 相似文献
173.
Phytoremediation is a promising new method that uses green plants to cleanse soil and water contaminated with organic or inorganic pollutants. In this study, the uptake and transformation of sodium perchlorate (NaClO4) using four vascular plant species were examined in batch experiments. The species include two trees, cabbage gum (Eucalyptus amplifolia) and eastern cottonwood (Populus deltoides), a herbaceous wetland plant, perennial glasswort (Salicornia virginica), and a herbaceous aquatic plant, waterweed (Elodea canadensis). Perchlorate was depleted from solution in the presence of all but one species (waterweed). Depletion was calculated as a first‐order kinetics reaction with k values in the range of 0–0.013 per day and accumulation of perchlorate was between 3.2 and 3138 mg/kg. Perchlorate and transformation metabolites (chlorate, chlorite, chloride) were observed in all plant tissues (e.g., roots, stems, leaves) analyzed. Results suggest that significant influences on perchlorate uptake include: (1) plant species present, (2) concentration of perchlorate, (3) sand versus hydroponic treatments, (4) the presence or absence of plant nutrients or competing ions, (5) stage of plant maturity. 相似文献
174.
Ludwig Benner Jr. 《Safety Science》2012,50(6):1431-1437
This paper describes concerns about the documentation, dissemination and use of lessons learned from mishap investigations, impediments posed by current practices, and opportunities for improvement. Lessons are presently developed, documented and stored primarily in narrative form and relational databases, and disseminated in many forms and media, including the Internet. Current practices pose many impediments to maximized development, dissemination and use. Investigation process research and new data concepts behind the Semantic Web, exploited elsewhere, offer potential opportunities to overcome these impediments. To exploit these opportunities, formation of a working group to develop an improved Semantic Web-friendly mishap investigation lessons learning system is proposed. An example illustrating an alternative approach is described to support a reasonable expectation that an alternative lessons learning system could be developed. 相似文献
175.
The application of predicted habitat models to investigate the spatial ecology of demersal fish assemblages 总被引:1,自引:0,他引:1
Benthic habitats are known to influence the abundance and richness of demersal fish assemblages; however, little is known
about how habitat structure and composition influences these distributions at very fine scales. We examined how the benthic
environment structures marine fish assemblages using high-resolution bathymetry and accurate predicted benthic habitat maps.
Areas characterised by a mosaic of habitat patches supported the highest richness of demersal fishes. A total of 37.4% of
the variation in the distribution of the fish assemblage was attributed to 6 significant variables. Depth explained 23.0%
of the variation, with the boulders explaining 12.6% and relief 1.4%. The remaining measures (seawhips, light/exposure and
solid reef) provided a small (<1.0%) but significant contribution. Identifying components of the benthic environment important
in structuring fish assemblages and understanding how they influence the spatial distribution of marine fishes is imperative
for better management of demersal fish populations. 相似文献
176.
The Wanjiazhai Water Transfer Project, now under development by the Shanxi Province of China with World Bank assistance, is a pioneering undertaking providing massive integrated water transfer, to enable the 'parched' regions of northern China to be able to survive. The Wanjiazhai project will deliver some 1.76 million m3/day of fresh water from the Wanjiazhai Reservoir on the Yellow River, by means of a series of pumping stations tunnels, and other components, over a distance of some 285 km to the City of Taiyuan, which is the hub of one of China's major industrial zones. Due to the continuing growth of population and of associated industry and agriculture, the local water resources have become totally overutilised, although extensive recycling for industry and irrigation occurs. The current sustainability of the groundwater resources is seriously threatened, for the present water shortage is 0.43 million m3/day. In addition, because of the large production of pollutant discharges with insufficient attention to waste management, the local river has become grossly polluted. The only answer is a massive importation of water, which is the first step in the project now underway.The focus of the present paper is to examine how the overall project will incorporate essential components to ensure that the expensive imported water will be wisely utilized. To manage this problem the overall project includes a number of special components including: (i) a critical assessment of the new total water resources availability and its allocation between various users, including a pricing structure which assigns equal value to both local and imported water supplies, (ii) an optimization of use of clean technologies and of recycling by industries, as well as improved waste treatment, including the establishment of a financial revolving fund to assist in achieving these goals, (iii) a substantial strengthening of the community/regional water pollution control management operations, with adequate funding, so as to upgrade the municipal wastewater treatment system to restore the river to acceptable water quality levels and, (iv) the recharging of the groundwater basins with treated sewage effluents, plus recharging using floodwater runoff during the rainy seasons. 相似文献
177.
178.
Mary K. Hendrickson Harvey S. JamesJr. 《Journal of Agricultural and Environmental Ethics》2016,29(6):945-967
The (un)fairness of agricultural markets is frequently invoked, especially by farmers. But fairness is difficult to define and measure. In this paper we link fairness and power with the concept of constrained choice to develop a framework for assessing fairness in agricultural markets. We use network exchange theory to define power from the dependencies that exist in agricultural networks. The structure of agricultural networks and the options that agricultural producers have to participate in agricultural networks affect the degree to which they are dependent on others within the network. Dependency, in turn, affects the choices that agricultural producers have. We consider both the number and nature of these choices. We argue that constraining or limiting choices—both in number and type—violates principles of justice. Importantly, network exchange theory provides a method for assessing constraints in choices and, hence, the fairness of agricultural markets. Such an assessment could potentially lead to new policies that safeguard the liberties of marketplace participants. We present a brief case to illustrate how this framework can inform on the fairness of agricultural markets and conclude with considerations of what this means for policy, particularly in the arena of anti-trust. 相似文献
179.
Steven Van Passel Guido Van Huylenbroeck Ludwig Lauwers Erik Mathijs 《Journal of environmental management》2009,90(10):3057-3069
Appropriate assessment of firm sustainability facilitates actor-driven processes towards sustainable development. The methodology in this paper builds further on two proven methodologies for the assessment of sustainability performance: it combines the sustainable value approach with frontier efficiency benchmarks. The sustainable value methodology tries to relate firm performance to the use of different resources. This approach assesses contributions to corporate sustainability by comparing firm resource productivity with the resource productivity of a benchmark, and this for all resources considered. The efficiency is calculated by estimating the production frontier indicating the maximum feasible production possibilities. In this research, the sustainable value approach is combined with efficiency analysis methods to benchmark sustainability assessment. In this way, the production theoretical underpinnings of efficiency analysis enrich the sustainable value approach. The methodology is presented using two different functional forms: the Cobb–Douglas and the translog functional forms. The simplicity of the Cobb–Douglas functional form as benchmark is very attractive but it lacks flexibility. The translog functional form is more flexible but has the disadvantage that it requires a lot of data to avoid estimation problems. Using frontier methods for deriving firm specific benchmarks has the advantage that the particular situation of each company is taken into account when assessing sustainability. Finally, we showed that the methodology can be used as an integrative sustainability assessment tool for policy measures. 相似文献
180.
P. Doukakis V. J. Birstein R. DeSalle A. N. Ludwig A. Ludwig A. Machordom A. Almodóvar B. Elvira 《Marine Biology》2000,136(2):373-377
MtDNA analyses were employed to examine the species identification of three preserved museum sturgeon specimens from the River Guadalquivir, two of which were originally described as Acipenser sturio L., 1758 by Hernando (1975; Doñana, Acta Vertd 2: 263–264). Later the same two specimens were identified as A. naccarii Bonaparte, 1836 by Garrido-Ramos et?al. (1997; Mar Biol 129: 33–39) on the basis of morphometric and nuclear DNA analyses. Three different laboratories using independent techniques were unsuccessful in extracting authentic DNA from tissue samples from the three specimens and in obtaining any verifiable PCR product. We cannot confirm the previous molecular identification of two of these specimens by Garrido-Ramos et?al. as A. naccarii. We suggest that these specimens are indeed A. sturio. 相似文献