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1.
International trade in fishery commodities reached US 58.2 billion dollars in 2002, a 5% improvement relative to 2000 and a 45% increase over 1992 levels. Within this global trade, developing countries registered a net trade surplus of US 17.4 billion dollars in 2002 and accounted for almost 50% by value and 55% of fish exports by volume. This globalization of fish trade, coupled with technological developments in food production, handling, processing and distribution, and the increasing awareness and demand of consumers for safe and high quality food have put food safety and quality assurance high in public awareness and a priority for many governments. Consequently, many countries have tightened food safety controls, imposing additional costs and requirements on imports. As early as 1980, there was an international drive towards adopting preventative HACCP-based safety and quality systems. More recently, there has been a growing awareness of the importance of an integrated, multidisciplinary approach to food safety and quality throughout the entire food chain. Implementation of this approach requires an enabling policy and regulatory environment at national and international levels with clearly defined rules and standards, establishment of appropriate food control systems and programmes at national and local levels, and provision of appropriate training and capacity building. This paper discusses the international framework for fish safety and quality, with particular emphasis on the United Nation's Food and Agricultural Organization's (FAO) strategy to promote international harmonization and capacity building.  相似文献   

2.
Consumers world-wide are driving changes in the agriculture and food sector. Rising consumer income, changing demographics and lifestyles, and shifting preferences due to new information about the links between diet and health all contribute to new demands for foods. At the same time, technological changes in production, processing and distribution, growth in large-scale retailing, and changes in product availability, as well as expansion of trade world wide, have contributed to a rapidly changing market for food products. Changes in seafood consumption reflect these changes. The changes in consumer consumption patterns, new technologies and trade in product offer both expanded markets as well as new challenges to consumer exposure to food-borne risks. The strict quality control requirements of retail brokers, growth of private labels, and development of value-protecting marketing channels have become increasingly important in food markets. This paper addresses major trends that affect seafood consumption and the market for seafood products and the implications of these changes for consumer risk exposure to food safety hazards. The current economic environment highlights similarities and differences between the developed and developing countries, as well as diversity worldwide in consumption of seafood. Within this context, four major trends affect consumer consumption of foods, including seafood and fish products today: rising income; changing demographics; changing markets for food; and an increasingly global market for food products. Changes in consumer risk exposure to food safety problems are addressed in the context of these trends.  相似文献   

3.
Countries need to know what species are present within their waters to effectively manage the issue of non-indigenous marine species. Five survey methods are currently employed to detect introduced marine species: the Hewitt and Martin protocols (66% of effort; 73 ports, 12 countries); Rapid Assessment Surveys (7% of effort; 8 regions, 4 countries); the Bishop Museum protocols (7% of effort; 8 ports, 3 countries); the Chilean aquaculture surveys (1% of effort; numerous regions; 1 country); and Passive Sampling protocols (18% of effort; 20 ports, 2 countries). These methods use either quantitative, qualitative, or a mixture of the two sampling techniques and tend to target locations that are potential inoculation sites (i.e., such as ports, marinas and aquaculture facilities). To date, introduced marine species surveys have been implemented in 19 countries and have detected more than 1185 non-indigenous, 735 cryptogenic and 15,315 native species.  相似文献   

4.
地震安全示范社区建设标准研究   总被引:1,自引:0,他引:1  
根据中国地震局的统一部署,近几年多个省份开展了地震安全示范社区建设,从加强抗震设防到应急预案编制、志愿者队伍建设、宣传教育等各个方面都不同程度地开展了工作。但现有的地震安全示范社区建设还没有统一建设和评价标准,建设水平也有较大的差距,对于推进这一工作的开展十分不利。本文通过系统的资料收集和调研,结合在大连市开展的具体实践,对地震安全示范社区建设与研究现状进行了分析,综合各省市实践经验和行业管理办法,参考安全社区建设方面的标准和管理规定,给出了地震安全社区的定义、建设标准应包含的要素及主要内容,讨论了应用前景和可能存在的问题,为今后全国范围内进一步开展此项工作提供了依据,也为制定行业标准奠定了基础。  相似文献   

5.
Biosecurity management allows countries to meet a number of international obligations and provides some protection from potential degradation of environmental, economic, social and cultural values. Ocean governance relies on the precepts of ecologically sustainable development to manage the multiple uses in the coastal zone. The increasing reliance on aquaculture to provide food security and economic development has led to an increase in the use of non-native target species grown as food sources. Increased economic activity has led to shifting trade patterns and increased efficiencies in vessels with the resulting increase in the number of introduced marine species via ballast water and hull fouling. Herein we review the different marine biosecurity strategies and legislation that have been implemented internationally and locally that aid in preventing and managing introduced marine species, with some attention to Australia and New Zealand as examples. Typical tools being used include quarantine, Import Health Standards, voluntary cleaning guidelines, and risk assessment, all of which aim to prevent introductions.  相似文献   

6.
Paleomagnetic and rock-magnetic studies on a hydraulic piston core (Ver98-1, St.6) from Academician Ridge, Lake Baikal showed the occurrence of a reversal excursion at 670-696 cm depth, which is at the base of marine oxygen isotope stage 6. A correlation of X-ray CT values, as a proxy of relative density, to the marine oxygen isotope record provides an age of 177-183 ka for this reversal excursion. It can be correlated with other excursion records from Lake Baikal, found in Core 287-K2 from Academician Ridge [King et al., Russ. Geol. Geophys. 34 (1993) 148-162] and in core BDP93-1 drilled on the Buguldeika saddle [BDP-93, Quat. Int. 37 (1997) 3-17]. We correlate the Lake Baikal reversal excursion with a well documented excursion in the Brunhes Chron, the Iceland Basin event (186-189 ka) from ODP Sites 983 and 984 in the North Atlantic [Channell, J. Geophys. Res. 104 (1999) 22937-22951]. Also the relative paleointensity record agrees well with that from ODP Site 983 [Channell, J. Geophys. Res. 104 (1999) 22937-22951]. The Lake Baikal excursion and the Iceland Basin event correspond to the minimum of relative intensity at 188 ka in Sint-800 [Guyodo and Valet, Nature 399 (1999) 249-252]. We argue that it is distinct from the Jamaica/Pringle Falls excursion, estimated at 205-215 ka [Langereis et al., Geophys. J. Int. 129 (1997) 75-94]. This is supported by the recalibration of the age of another excursion found in Core St.16 in Lake Baikal [Sakai et al., Bull. Nagoya Univ. Furukawa Mus. 13 (1997) 11-22] with an age of ∼223 ka, which is close to the age of the Jamaica/Pringle Falls excursion, as suggested earlier [King et al., Russ. Geol. Geophys. 34 (1993) 148-162]. The VGP path of the reversal excursion (177-183 ka) consists of a southward swing through the North Atlantic, followed by a loop through Africa and the Indian Ocean. The path morphology is similar to that of the Iceland Basin event from the North Atlantic [Channell, J. Geophys. Res. 104 (1999) 22937-22951].  相似文献   

7.
BOOK REVIEWS     
《Geophysical Prospecting》1966,14(2):218-221
K. J ung , Schwerkraftverfahren in der angewandten Geophysik (Gravity Methods in Applied Geophysics), Akademische Verlagsgesellschaft Geest & Portig KG., Leipzig, 1961, 348 pp., price: 48,– DM.
R. M einhold , Geophysikalische Meβverfahren in Bohrungen , Geophysikalische Monographien Bd. 4, Akademische Verlagsgesellschaft Geest & Portig KG., Leipzig, 1965, 237 pp., 125 figs., 13 tables, size 8°, price: 55,– MDN.
G eorge B. C lark , International Symposium, on Mining Research, Proceedings of a Symposium held at the University of Missouri (2 Volumes), Pergamon Press Ltd., Oxford, London, New York, 1962, 859 pages, price: γ 10 per set.
I. D. S avinskii , Probability Tables for Locating Elliptical Underground Masses with a Rectangular Grid , explanatory text translated from Russian, Consultants Bureau Enterprises Inc., New York, 1965, price: $ 15.
The World of Geology , edited by L. D onleet and F lorence J. L eet , McGraw-Hill Publishing Comp. Ltd., London, 1961, price: 21s 6d.
H. G. F. W inkler , Die Genese der metamorphen Gesteine . Springer-Verlag, Berlin, Heidelberg, New York, 1965, 40 Figs., VIII, 218 pages, size 8°, price: 19,80. DM  相似文献   

8.
Centroid–moment-tensor solutions are presented for 1034 earthquakes that occurred during 2002. The solutions are obtained using the method of Dziewonski et al. [Dziewonski, A.M., Chou, T.-A., Woodhouse, J.H., 1981. Determination of earthquake source parameters from waveform data for studies of global and regional seismicity. J. Geophys. Res. 86, 2825–2852] and applying corrections for aspherical Earth structure represented by the whole-mantle shear-velocity model SH8/U4L8 of Dziewonski and Woodward [Dziewonski, A.M., Woodward, R.L., Acoustic imaging at the planetary scale, in: Emert, H., Harjes, H.-P. (Eds.), Acoustical Imaging, vol. 19. Plenum Press, New York, 1992, pp. 785–797]. The model of anelastic attenuation of Durek and Ekström [Durek, J.J., Ekström, G., 1996. A radial model of anelasticity consistent with long-period surface wave attenuation. Bull. Seism. Soc. Am. 86, 144–158] is used to predict the decay of the waveforms. The focal mechanisms of the largest, or otherwise significant, earthquakes of 2002 are reviewed.  相似文献   

9.
Centroid–moment-tensor (CMT) solutions are presented for 1087 earthquakes that occurred during 2003. The solutions are obtained using the method of Dziewonski et al. [Dziewonski, A.M., Chou, T.-A., Woodward, J.H., 1981. Determination of earthquake source parameters from waveform data for studies of global and regional seismicity. J. Geophys. Res. 86, 2825–2852] and applying corrections for aspherical Earth structure as represented by the whole-mantle shear-velocity model SH8/U4L8 of Dziewonski and Woodward [Dziewonski, A.M., Woodward, R.L., 1992. Acoustic imaging at the planetary scale. In: Emert, H., Harjes, H.-P. (Eds.), Acoustical Imaging, vol. 19. Plenum Press, New York, pp. 785–797]. The model of inelastic attenuation of Durek and Ekström [Durek, J.J., Ekström, G., 1996. A radial model of inelasticity consistent with long-period surface wave attenuation. Bull. Seism. Soc. Am. 86, 144–158] is used to predict the decay of the waveforms. The focal mechanisms of the largest, or otherwise significant, earthquakes of 2003 are reviewed.  相似文献   

10.
Fish discards and by-catch issues are highly topical subjects that are permanently under a social focus. Two main approaches are being considered to address this discard problem: reducing the by-catch and increasing by-catch utilization. Interest in increased by-catch valorization may arise from a greater demand for fish products, such as the development of new markets for previously discarded species, the use of low-value specimens for aquaculture or the creation of value-added fish products for the food, pharmaceutical or cosmetic industries. However, contaminants present in fish discards may be transferred to their valorized products, leading to possible long-term bioaccumulation and subsequent adverse health effects. In this valorization framework, the aim is to promote responsible and sustainable management of marine resources. The pollutant levels in catches from European fisheries and the best available decontamination techniques for marine valorized discards/by-products are compiled and analyzed in this work.  相似文献   

11.
We report optically stimulated luminescence (OSL) dating results from the Old Cedar midden in St. Joseph Peninsula State Park, located between the Gulf of Mexico and St. Joseph Bay near Port St. Joe, FL, USA. The Old Cedar site (8GU85) is located on top of a relict beach ridge which is actively eroding into St. Joseph Bay. Old Cedar is noted for its conch shell tool assemblage, otherwise rare at northwest Florida archaeological sites, and is believed to have been utilized during the Late Woodland Weeden Island and possibly the Fort Walton periods [Benchley, E.D., Bense, J.A., 2001. Archaeology and history of St. Joseph Peninsula State Park: Phase I investigations. Report of Investigations, No. 89, University of West Florida Archaeology Institute]. After removing surficial erosion deposits, we extracted OSL core samples from both the midden layer and the underlying beach ridge. The resulting OSL age is compared with the age of another beach ridge on St. Joseph Peninsula. We hope that this study will aid in the investigation and conservation of Old Cedar specifically and other Weeden Island sites in the St. Joseph Bay area.  相似文献   

12.
The experimental results for the mechanical response of sand (at different levels of saturation with water) under shock-loading conditions generated by researchers at Cavendish [Bragov AM, Lomunov AK, Sergeichev IV, Tsembelis K, Proud WG. The determination of physicomechanical properties of soft soils from medium to high strain rates, November 2005, in preparation; Chapman DJ, Tsembelis K, Proud WG. The behavior of water saturated sand under shock-loading. In: Proceedings of the 2006 SEM annual conference and exposition on experimental and applied mechanics, vol. 2, 2006.p.834–40] are used to parameterize our recently developed material model for sand [Grujicic M, Pandurangan B, Cheeseman B. The effect of degree of saturation of sand on detonation phenomena associated with shallow-buried and ground-laid mines. J Shock Vib 2006;13:41–61]. The model was incorporated into a general-purpose non-linear dynamics simulation program to carry out a number of simulation analyses pertaining to the detonation of a landmine buried in sand and to the interactions of the detonation products, mine fragments and sand ejecta with various targets. A comparison of the computed results with their experimental counterparts revealed a somewhat improved agreement with the experimental results in the case of the present model as compared to the agreement between the widely used porous-material/compaction model for sand and the experiments.  相似文献   

13.
Data collected from a GPS receiver located at low latitudes in the American sector are used to investigate the performance of the WinTEC algorithm [Anghel et al., 2008a, Kalman filter-based algorithm for near realtime monitoring of the ionosphere using dual frequency GPS data. GPS Solutions, accepted for publication; for different ionospheric modeling techniques: the single-shell linear, quadratic, and cubic approaches, and the multi-shell linear approach. Our results indicate that the quadratic and cubic approaches perform much better than the single-shell and multi-shell linear approaches in terms of post-fit residuals. The performance of the algorithm for the cubic approach is then further tested by comparing the vertical TEC predicted by WinTEC and USTEC [Spencer et al., 2004. Ionospheric data assimilation methods for geodetic applications. In: Proceedings of IEEE PLANS, Monterey, CA, 26–29 April, pp. 510–517] at five North American stations. In addition, since the GPS-derived total electron content (TEC) contains contributions from both ionospheric and plasmaspheric sections of the GPS ray paths, in an effort to improve the accuracy of the TEC retrievals, a new data assimilation module that uses background information from an empirical plasmaspheric model [Gallagher et al., 1988. An empirical model of the Earth's plasmasphere. Advances in Space Research 8, (8)15–(8)24] has been incorporated into the WinTEC algorithm. The new Kalman filter-based algorithm estimates both the ionospheric and plasmaspheric electron contents, the combined satellite and receiver biases, and the estimation error covariance matrix, in a single-site or network solution. To evaluate the effect of the plasmaspheric component on the estimated biases and total TEC and to assess the performance of the newly developed algorithm, we compare the WinTEC results, with and without the plasmaspheric term included, at three GPS receivers located at different latitudes in the American sector, during a solar minimum period characterized by quiet and moderate geomagnetic conditions. We also investigate the consistency of our plasmaspheric results by taking advantage of the specific donut-shaped geometry of the plasmasphere and applying the technique at 12 stations distributed roughly over four geomagnetic latitudes and three longitude sectors.  相似文献   

14.
核电厂地震安全性评价中的断裂构造调查与评价   总被引:1,自引:1,他引:1  
本文针对当前工作中存在的问题,对核电厂地震安全性评价工作中断裂构造调查与评价的技术思路、发震构造鉴定、能动断层鉴定与调查、地表断裂影响评价、发震构造与能动断层的关系等方面的问题,从核安全法规的层面进行了分析和讨论。认为对核安全法规的正确认识和理解,是较好地解决当前问题的重要途径。  相似文献   

15.
Coral reef fisheries are critical for food security and as a source of income in developing and developed countries, but they are collapsing in many areas. Following the emergence and routine availability of commercial very high spatial resolution (0.6-10 m) multispectral satellite images, we reviewed the use of these new high-quality remote sensing data and products for coral reef fisheries management. The availability of habitats maps improves management by guiding sampling strategies, mapping resources, involving local communities, identifying conservation areas, and facilitating Ecosystem Based Fishery Management (EBFM) approaches. However, despite their potential, very little use of products designed specifically for fishery management can be reported, likely due to high costs, inherent technology limitations and lack of awareness on the possibilities. Given the theoretical benefits brought by relevant habitat maps in EBFM frameworks, we advocate the use of adequate remote sensing products that integrate fishery technical services demands and local requirements.  相似文献   

16.
To compare water quality in rivers of developed and developing countries, a study based on physicochemical parameters and dissolved metals levels was conducted. Water samples were collected from selected sites in Dhaka, Bangladesh; Hokkaido and Osaka, Japan; Erdenet, Mongolia and West Java, Indonesia. Analysis of least significant differences revealed that most water quality parameters were within comparable low levels in both developed and developing countries. The dissolved metals concentrations were found to be similar and below those of water standards except for manganese and cadmium at every sampling point, and lead in Erdenet, Mongolia. Some metals showed high enrichment factors in the rivers of Osaka, Japan and Erdenet, Mongolia, indicating accumulation possibility of metals in the river‐bed sediments. High concentrations of dissolved organic carbon, Escherichia coli and dissolved metals suggested greater water pollution in some rivers of developing countries than in the rivers of Japan. Principal component analysis showed strong correlations between “dissolved organic carbon and chemical oxygen demand” and “conductivity and total dissolved solids” at each sampling point, and E. coli, nitrate (NO), nitrite (NO), and pH levels were found to be higher in the rivers of Dhaka and Erdenet. In addition, there were high levels of Al and Zn in West Java, Pb in Erdenet, and Mn, Fe, and Cr in the rivers of Dhaka and Japan. Based on pressures and impacts, it is evident that dissolved metal, organic, and fecal pollution in the rivers of developing countries are in somewhat dreadful condition in comparison with the rivers of developed country.  相似文献   

17.
陶玲  彭亮  代梨梨  杨镇  陈思媛  可毅  李谷 《湖泊科学》2023,35(1):168-180
为探明稻虾轮作模式面源污染排放特征并合理评价该模式的环境可持续性,通过对江汉平原稻虾轮作模式小龙虾养殖排放尾水中总氮(TN)、总磷(TP)、COD和氨氮(NH3-N)浓度进行监测,对稻虾轮作模式稻田养殖小龙虾的排污系数进行了估算,并采用等标污染负荷法进行了主要污染物解析。运用能值分析方法对稻虾轮作模式进行了包含面源污染的能值评估,对比单季稻模式,对其可持续发展能力进行了定量评价。结果表明:江汉平原稻虾轮作模式小龙虾养殖排放尾水中TN、TP、COD和NH3-N的浓度范围分别为0.53~5.36、0.12~0.70、6.60~78.39和0.34~1.75 mg/L,TN、TP和COD平均排放浓度高于《地表水环境质量标准》(GB 3838-2002)Ⅲ类水质标准。等标污染负荷法分析结果表明TN的等标负荷比最高,是稻虾轮作模式面源污染控制的关键污染物。稻虾轮作模式小龙虾养殖排放尾水中TN、TP、COD和NH3-N的排污系数分别为2.994、0.458、35.132和1.405 kg/t,表明稻虾轮作模式面源污染排放系数较低,对...  相似文献   

18.
Book reviews     
Abstract

EDDIES IN MARINE SCIENCE (Edited by A. R. Robinson) Springer-Verlag, 1983, 268 figures, 625 pages. Price: DM 120 (U.S. $49.60). ISBN 3-540-12253-2

THE SOLAR GRANULATION, by R. J. Bray, R. E. Loughhead, and C. J. Durrant, 2nd Ed., Cambridge University Press 1984. xvi + 245 pp. Price: £27.50, $54.50, ISBN 0-521-24714-4.

ASTROPHYSICAL JETS. Proceedings of an International Workshop held in Torino, Italy. October 7–9, 1982. Edited by A. Ferrari and A. G. Pacholczyk, D. Reidel Publishing Company, 1983. xvi + 327 pp. Dfl. 110.00 (US. $48.00). ISBN 90-277-1627-7.

INTERNAL KINEMATICS AND DYNAMICS OF GALAXIES. IAU Symposium No. 100. Edited by E. Athanassoula. D. Reidel Publishing Company, xiv + 432 pp. 1983. Price: Dfl. 115 (U.S. $49.50) ISBN 90-277-1546-7

HANDBOOK OF PLASMA PHYSICS—BASIC PLASMA PHYSICS 1. Edited by A. A. Galeev and R. N. Sudan. North-Holland Publishing Company 1983. 730 pages. Price: US. $180.75 (Dfl. 425.00). ISBN 0-444-86427-x.

NUMERICAL METHODS FOR FLUID DYNAMICS. Edited by K. W. Morton, xiv + 517 pp, Price $55.50 (£30). ISBN 0-12-508360-2.

MAGNETIC FIELDS IN ASTROPHYSICS, By Ya. B. Zeldovich, A. A. Ruzmaikin and D. D. Sokoloff. Gordon and Breach Science Publishers, xvi + 365 pp. 1984. Price $60.00. ISBN 0-677-05530-7 (Vol. 3 in “The Fluid Mechanics of Astrophysics and Geophysics” ISSN 0260 4353).  相似文献   

19.
Reducing marine-based public health risk requires strict control of several attributes of seafood products, often including location and conditions of catch or aquaculture, processing, and handling throughout the supply chain. Buyers likely will also be interested in other attributes of these products such as eco-friendliness or taste. Development of markets for improved safety, as well as for other quality attributes, requires an effective certification and tracking of these attributes as well as their communication to buyers. Several challenges must be met if labeling, particularly consumer labeling, is to support the development of markets for improved seafood safety.  相似文献   

20.
The earthquake of 26 September 1997 in Central Italy is one of the largest seismic events of the last 20 years in Italy. Two main events that caused significant damage in a large area of Umbria and Marche regions and site amplification phenomena were recorded even at large distances from the epicenter. After the emergency period, a detailed study of the surface effects was necessary for the post-earthquake reconstruction, but in a way it should be carried out rapidly enough to allow urban planners to give instructions and codes to public administrators. A team of surveyors were trained to collect field information such as geologic and geomorphologic features and, where possible, pre-existing geotechnic or geophysic information. Information was collected and analyzed with the aid of dynamic codes to calculate the possible local site effects. A one-dimensional code, analyzing single soil columns, [Schabel PB, Lysmer J, Seed HB. , a computer program for earthquake response analysis of horizontally layered sites. College of Engineering, University of California, Berkeley, Report PB-220. 1972, p. 207], as well as the two-dimensional codes working with finite or boundary elements, [Idriss IM, Lysmer J, Hwang R, Seed HB. , a computer program for evaluating the seismic response of the soil structure by variable damping finite element procedures. UCB EERC Report No. 73-16. 1973.] and [Sanò T. , un programma per il calcolo della propagazione delle onde sismiche. Technical Report SSN/RT/96/9. 1996, pp. 51.], were used and the results are presented as response spectra or amplification coefficients.  相似文献   

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