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71.
/ Protected area management is increasingly important throughout the world, particularly in less developed countries and arid regions. The Middle East, includingJordan, has important and unique resources due to its varied topography and climate. In Jordan, the protected areas are privately, rather than publicly, managed, and this provides for a unique and somewhat challenging management effort. The purpose of this paper is to review the establishment and administration of Jordan's protected areas with particular emphasis on the challenges of multiple administrative and legislative layers, departmental working relationships, and a paucity of funding. Interviews with government and nongovernmental experts in Jordan, coupled with a review of pertinent academic and planning literature, served as the information base for this study. Despite new legislative and administrative initiatives, results reveal important and continuing challenges for Jordan. Recommendations include completion of protected area inventories, government wide institutional strengthening, partnering with organizations and the public, as well as legislative reexamination.  相似文献   
72.
Eriksson IS  Elmquist H  Nybrant T 《Ambio》2005,34(4-5):388-392
In order to assess the ecological sustainability of agricultural production systems, there is a need for effective tools. We describe an environmental systems analysis tool called SALSA (Systems Ana/ysis for Sustainable Agriculture). It consists of substance/material flow models in which the simulation results are interpreted with life-cycle assessment methodology. The application of SALSA is demonstrated in a case study in which three different ways of producing pigs are compared with respect to energy input and the environmental impacts of global warming, eutrophication, and acidification. The scenario that combined a low-protein diet without soy meal with an improved manure-management technique with low nitrogen losses was the best for all impact categories studied. The strength of the SALSA models was their capacity to capture consequences of management options that had an influence on several processes on a farm, which enabled the type of complex studies we describe.  相似文献   
73.
Assessing the environmental consequences of a chemical accident is a complex task. To date, the methods used to evaluate the environmental effects of an acute release of a chemical have often been based on measurements of chemical and physical variables deemed to be important, such as the concentration of the chemical. However, a broader strategy is needed to predict the environmental consequences of potential accidents during the planning process. An Environment-Accident Index (EAI), a simple tool based on such a strategy, has been developed to facilitate the consideration of a multitude of influential variables. The objectives of this study were to evaluate whether questionnaire-based expert panel's judgements could provide useful data on the environmental consequences of chemical spills, and an effective basis for further development of the EAI. As expected, the judgements did not agree perfectly, but they do give rough indications of the environmental effects, and highlight consistent trends that should be useful inputs for planning, prevention and decontamination processes. The different accidents were also judged to have caused everything from minor to very major effects in the environment, implying that a wide range of accident scenarios were represented in the material and covered by the EAI. Therefore, questionnaires and expert panel judgements can be used to collect useful data for estimating the likely environmental consequences of chemical accidents and for further development of the EAI.  相似文献   
74.
Two analytical methods have been evaluated for quantitative determination of de-conjugated chrysene metabolites in fish bile. High performance liquid chromatography-fluorescence (HPLC-F) and gas chromatography-mass spectrometry (GC--MS) were compared regarding instrumental and overall limits of detection (LOD) as well as recoveries for the following nine chrysene compounds: 1-, 2,- 3-, 4- and 6-hydroxychrysene (1-, 2-, 3-, 4- and 6-OH-chr), 1,2-dihydroxy-1,2-dihydrochrysene (1,2-DHD-chr), 3,4-dihydroxy-3,4-dihydrochrysene (3,4-DHD-chr), 5,6-dihydroxy-5,6-dihydrochrysene (5,6-DHD-chr) and chrysene. Instrumental LODs were comparable for the two methods whereas the overall LOD was better for HPLC-F. Recoveries varied per chrysene compound for both HPLC-F (62-107%) and GC-MS (48-124%). In vivo formed chrysene metabolites were studied in the bile of Atlantic cod (Gadus morhua) exposed to chrysene (1 mg/kg) via intra-peritoneal (i.p.) and inter-muscular (i.m.) injection. Total amounts of chrysene metabolites were three times higher in i.p. compared to i.m. exposed cod bile, but the relative distribution of determined metabolites was very similar. 1,2-DHD-chr was the most prominent metabolite in de-conjugated bile and constituted more than 88% of the total chrysene metabolites. Additional chrysene metabolites formed were 3,4-DHD-chr and 1-, 2-, 3- and 4-OH-chr. K-region chrysene metabolites (oxidation at carbons 5 and 6) were not detected and seem to be a less favoured biotransformation route. The two methods were applied and evaluated for analysis of chrysene metabolites in two bile reference materials (BCR 720 and 721) and a limited number of field exposed cods.  相似文献   
75.
The ever‐widening scope and range of global change and interconnected systemic risks arising from people–environment relationships (social‐ecological risks) appears to be increasing concern among, and involvement of, citizens in an increasingly diversified number of citizen science projects responding to these risks. We examined the relationship between epistemic cultures in citizen science projects and learning potential related to matters of concern. We then developed a typology of purposes and a citizen science epistemic‐cultures heuristic and mapped 56 projects in southern Africa using this framework. The purpose typology represents the range of knowledge‐production purposes, ranging from laboratory science to social learning, whereas the epistemic‐cultures typology is a relational representation of scientist and citizen participation and their approach to knowledge production. Results showed an iterative relationship between matters of fact and matters of concern across the projects; the nexus of citizens’ engagement in knowledge‐production activities varied. The knowledge‐production purposes informed and shaped the epistemic cultures of all the sampled citizen science projects, which in turn influenced the potential for learning within each project. Through a historical review of 3 phases in a long‐term river health‐monitoring project, we found that it is possible to evolve the learning curve of citizen science projects. This evolution involved the development of scientific water monitoring tools, the parallel development of pedagogic practices supporting monitoring activities, and situated engagement around matters of concern within social activism leading to learning‐led change. We conclude that such evolutionary processes serve to increase potential for learning and are necessary if citizen science is to contribute to wider restructuring of the epistemic culture of science under conditions of expanding social‐ecological risk.  相似文献   
76.
Aquaculture is the fastest growing animal producing sector in the world and is expected to play an important role in global food supply. Along with this growth, concerns have been raised about the environmental effects of escapees and pollution, fish welfare, and consumer health as well as the use of marine resources for producing fish feed. In this paper we present some of the major challenges salmon farming is facing today. We discuss issues of relevance to how to ensure sustainability, by focusing on animal production systems, breeding approaches, sources for feed ingredients, and genetic engineering strategies. Other crucial issues such as animal welfare, environmental quality, and ethics are elaborated with regard to relevance for the sustainability of aquaculture. Additionally, we comment on socio-economic distributive implications by intellectual property rights (IPR) strategies on access to genetic material and traceability. To improve sustainability of salmon farming we suggest that there is a need for new approaches to guide research, for identification of ethical issues, and for engaging stakeholders in resolving these challenges.  相似文献   
77.
The Mediterranean fanworm, Sabella spallanzanii Gmelin 1791, was first detected in the Southern Hemisphere in the 1990s and is now abundant in many parts of southern Australia and in several locations around northern New Zealand. Once established, it can proliferate rapidly, reaching high densities with potential ecological and economic impacts. Early detection of new S. spallanzanii incursions is important to prevent its spread, guide eradication or control efforts and to increase knowledge on the species’ dispersal pathways. In this study, we developed a TaqMan probe real-time polymerase chain reaction assay targeting a region of the mitochondrial cytochrome oxidase I gene. The assay was validated in silico and in vitro using DNA from New Zealand and Australian Sabellidae with no cross-reactivity detected. The assay has a linear range of detection over seven orders of magnitude with a limit of detection reached at 12.4 × 10?4 ng/μL of DNA. We analysed 145 environmental (water, sediment and biofouling) samples and obtained positive detections only from spiked samples and those collected at a port where S. spallanzanii is known to be established. This assay has the potential to enhance current morphological and molecular-based methods, through its ability to rapidly and accurately identify S. spallanzanii in environmental samples.  相似文献   
78.
Human serum and plasma from Sweden (n=17), the United Kingdom (the UK) (n=13) and Australia (n=40) were analyzed by high performance liquid chromatography coupled to mass spectrometry. The objective was to identify different perfluorooctane sulfonate (PFOS) isomers. Similar isomer patterns typical for the electrochemical fluorination (ECF) process were found for all samples. The linear PFOS (L-PFOS) was the major isomer found (58-70%) followed by the monosubstituted PFOS isomers 1/6-CF(3)-PFOS (18-22%) and 3/4/5-CF(3)-PFOS (13-18%). Disubstituted isomers were also detected. The percentage of L-PFOS found in the serum and plasma samples was lower compared to a standard PFOS product (76-79%). The pattern of PFOS isomers in human serum and plasma may be suggestive concerning potential isomeric discrimination since PFOS is only produced by ECF. Possibilities for such isomer discrimination are discussed. Significant higher content of L-PFOS (68%) in Swedish samples compared to Australia and the UK (59%) was also found, which may suggest differences in exposure sources for humans.  相似文献   
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