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11.
《Marine Policy》2014
Mitigating the environmental impact of commercial fishing, by avoiding, minimizing and compensating for adverse effects, is core business for fisheries management authorities globally. The complex interplay of ecological, economic, and social considerations has often resulted in bycatch management being reactive, confrontational and costly. In many cases it has been difficult to demonstrate success and to establish whether bycatch management has been efficient or effective. This article proposes standards for bycatch management following reviews of literature, international agreements and Australian domestic fishery management policies, and consideration by many technical experts and several stakeholder representatives. The standards have been developed using Australian Commonwealth fisheries – and the international fisheries agreements to which Australia is party – as a baseline, but should be applicable to both domestic and regional/international governance systems. The proposed standards involve quantifying fisheries bycatch, agreeing on operational objectives, assessing the effects of fishing on bycatch populations, establishing the cost-effectiveness of mitigation measures, and evaluating performance. The standards encourage domestic management measures that are consistent with the guidance and requirements of international agreements and regional fisheries management organisations. The importance of engaging stakeholders throughout the process is recognised. The standards provide a framework for measuring performance and a checklist of actions for managing bycatch at a fishery level. They have the potential to facilitate the development of more strategic and effective approaches to bycatch management, with defined goals, monitoring systems, and adaptive decision-making. This review of past bycatch management, including the application of the proposed standards to the mitigation of shark bycatch in an Australian longline fishery, demonstrates that the proposed standards are operationally feasible but that they have not always been applied. Specifically, monitoring the performance of bycatch management measures has not always followed their implementation. 相似文献
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Twenty-eight samples of groundwater from bedrock boreholes in three distinct Norwegian geological provinces have been taken and analyzed for content of Rn, U, and Th, together with a wide variety of minor and major species. Median values of 290 Bq/1, 7.6 g/1, and 0.02 g/1 were obtained for Rn, U, and Th respectively, while maximum values were 8500 Bq/1, 170 g/1, and 2.2 g/1. Commonly suggested drinking water limits range from 8 to 1000 Bq/1 for radon and 14 to 160 g/1 for uranium. Radioelement content was closely related to lithology, the lowest concentrations being derived from the largely Caledonian rocks of the Trøndelag area, and the highest from the Precambrian Iddefjord Granite of southeast Norway (11 boreholes) where median values of 2500 Bq/1, 15 g/1 and 0.38 g/1, respectively, were obtained. The Iddefjord Granite is not believed to be unique in Norway in yielding high dissolved radionuclide contents in groundwaters, and several other granitic aquifers warrant further investigation in this respect. 相似文献
14.
A multi-residual method based on stir bar sorptive extraction coupled with thermal desorption-gas chromatography-mass spectrometry (SBSE-TD-GC-MS) has been developed to measure 49 organic pollutants (organochlorine pesticides, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, polybrominated diphenyl ethers and nonylphenol) in seawater. Using 100 ml of water, the method exhibited good linearity, with recoveries between 86% and 118% and relative standard deviation between 2% and 24% for almost all compounds. The method was applied to determine target contaminants in Catalonian seawater, including coastal areas, ports and desalination plant feed water. Overall individual compound levels oscillated between 0.16 and 597 ng l−1; PAHs and nonylpenol were the compounds found at the highest concentrations. The method provided LODs between 0.011 and 2.5 ng l−1, lower than the Environmental Quality Standards (EQS) fixed by Directive 2008/105/EC. In compliance with the directive, this method can be used as a tool to survey target compounds and is aimed at protecting coastal ecosystems from chemical pollution. 相似文献
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国标<旅游规划通则>是一个"早产儿",存在重大缺陷.首先是缺乏理论支撑,国标的指导思想带有很强的计划经济体制烙印,也没有可供依托的技术体系.其次,从实践层面看,国标中的绝大多数要求是无法完成的,也脱离我国旅游规划多头管理的现行体制,导致旅游规划的执行效果不佳.再次,从实施的结果看,国标既没能推动旅游规划事业的发展,也没有造就一支旅游规划人才队伍.因此,需要对其中的旅游规划指导思想、定位、目标、内容、技术指标、可实现性等进行系统的讨论. 相似文献
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In a 350 m wide reach of the braided, gravel-bed Ashley River, the surface layer of the bed material was sampled in 141 areas of homogeneous graded sediment along seven cross-sections, and 30 kg bulk samples were collected at 86 randomly selected locations along the cross-sections. At one location, a single 854 kg sample composed of 28 subsamples was also collected. Analysis of the single large sample indicate that accurate determination of mean grain size D at that site requires, desirably, a sample of ～ 100 kg, but that samples in which the weight of the largest stone is less than 5 per cent of the total weight have unbiased estimates of D. Spatial variability of bulk material is such that 228 and 50 samples are needed to estimate D to ± 10 and ± 20 per cent respectively of the true value; requirements for estimating inclusive graphic standard duration are only 11 and 3 respectively. The grain-size distribution of the surface layer is only weakly related to the bulk material beneath. The results of ‘Wolman sampling’ along 12 cross-sections at two pace intervals (average 120 stones per cross-section) indicate that estimation of overall surface D to ±10 and ±20 per cent would require sampling along 64 and 14 cross-sections respectively. It is concluded that accurate characterization of bed sediment in gravel-bed rivers is very demanding of labour and resources, and that careful planning is needed to ensure efficiency and meaningful results. 相似文献
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《The Journal of geography》2012,111(1):43-45
Abstract World Geomorphology, by E. M. Bridges New York Cambridge University Press. 260 pp. Cloth $70.00, Paperback—$24.95. ISBN 0-521-38343-9. Land Degradation, by C. J. Barrow New York: Cambridge University Press. 295 pp. Cloth—$80.00. ISBN 0-521-35333-5. An Outline of China's Physical Geography, by Ren Mei'e, Yang Renzhang, and Bao Haosheng, compilers, Zhang Tingquan and Hu Genkang, translators Beijing: Foreign Languages Press. 1985. 471 pp. Paperback—$15.00. ISBN 0-8351-1192-X. Earth Science for Every Kid: 101 Easy Experiments that Really Work, by Janice VanCleave New York John Wiley &; Sons. 1991. 231 pp. $19.89. SimEarth, by Maxis Software Orinda, CA: Maxis Software. $69.95. Black and white or color. School editions and lab packs are available at reduced prices from Broderbund Software, Novato, CA. For Macintosh and IBM compatible. MacGlobe, by PC Globe, Inc. Tempe, AZ: PC Globe, Inc. $79.95. For Macintosh. EARTHALERT, by Mike2, Inc. Seattle, WA: Mike2, Inc. Geo-Safari, by Educational Insights Geo-Safari, Educational Insights, 19560 South Rancho Way, Dominguez, Hills, CA 90220. 相似文献
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《The Journal of geography》2012,111(6):261-270
Abstract As a relevant aspect of contemporary culture, music is a significant part of the lifestyles of students at all levels of education. Thus, use of various genres of American music is framed in the context of the National Standards five themes of geography—location, movement, human-environment interaction, region, and place. Several classroom projects appropriate for grades 7–12 are identified, including data collection, map preparation, and development of a research paper. Teaching resources consist of references used in text, music geography bibliography in addition to references, data sources, useful music-related websites, and list of research paper topics. 相似文献
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《The Journal of geography》2012,111(1):46-48
Abstract Full implementation of geography standards will require their adoption by all U.S. states and school districts for use in every school. Strategies for achieving this goal include: using the consensus process to its fullest, involving the energy and resources of geography organizations, and reaching out to others to help maximize the standards' influence. 相似文献
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Looking Toward the Future: A Concepts,Themes, and Standards Approach to Preservice Teacher Education
《The Journal of geography》2012,111(5):513-518
Abstract Preservice teacher education based on content, skills, and perspectives specified in Geography for Life: National Geography Standards 1994 is essential for dissemination of the Standards to classrooms all across the country. Curricular materials are often structured around the five fundamental themes of geography; however, it is essential that teacher preparation courses integrate the content of the Standards into the themes of location, place, human—environment interaction, and region. One model of this approach to preservice education, as summarized here, provides future teachers with a conceptual basis for learning and teaching geography, enhancing opportunities for disseminating solid geography content to all grade levels nationwide. 相似文献