Pollution indicators,fish consumption and the accumulation of mercury in human hair

Mercury can accumulate in the human body from fish and from other environmental sources, and the amount accumulated is indicated by hair mercury concentration. Anthropogenic mercury losses in many countries have been correlated with Gross National Product (GNP, an indicator of industrial activity), and industrial density (represented by GNP/land area, i.e. GNP/LA) has been used as an indicator of potential pollution for coastal fishing grounds. For a data set taken from the literature, 30% of the 54% variability in hair mercury concentrations explained by national fish consumption can also be explained by GNP/LA. However, using new data, the effect of GNP and GNP/LA on the amount of mercury accumulated in hair of people from many countries was insignificant compared to the effect of national fish consumption. 74.1% of the variability in the hair mercury levels of people who ate the same number of meals of fish was explained by the national average fish consumption. This suggests that fish species and fish size are more important than general indicators of mercury pollution when estimating the mercury accumulation in humans on an international scale.     

Application of food waste based diets in polyculture of low trophic level fish: Effects on fish growth,water quality and plankton density

Food waste was collected from local hotels and fish feed pellets were produced for a 6 months long field feeding trial. Three types of fish feed pellets (control diet: Jinfeng® 613 formulated feed, contains mainly fish meal, plant product and fish oil; Diet A: food waste based diet without meat and 53% cereal; Diet B: food waste based diet with 25% meat and 28% cereal) were used in polyculture fish ponds to investigate the growth of fish (grass carp, bighead and mud carp), changes in water quality and plankton density. No significant differences in the levels of nitrogen and phosphorous compounds of water body were observed between 3 fish ponds after the half-year feeding trial, while pond receiving Diet A had the highest density of plankton. The food waste combination of Diet B seems to be a better formulation in terms of the overall performance on fish growth.     

Fisheries and aquaculture industries involvement to control product health and quality safety to satisfy consumer-driven objectives on retail markets in Europe

Over the past years the export of agricultural and fishery products from developing countries has substantially increased to markets within the OECD. Retailers and importers are expanding their international operations to meet consumer demands for year-round delivery of products. Moreover, consumers have become increasingly concerned about the safety of food, including those derived from aquatic resources [FAO/NACA/WHO Joint Study Group, 1999. Report food safety issues associated with products from aquaculture. WHO Technical Report Series No 883: VII, pp. 1-55]. Governments and leading businesses are responding by imposing new safety regulations and standards to the international food system (e.g. HACCP, EUREP-GAP), product liability and labeling [Reilly, A., Howgate, P., K?ferstein, F., 1997. Safety hazards and the application of HACCP in aquaculture. In: Proceedings of the Second International Conference on Fish Inspection and Quality Control: A Global Focus, Arlington, VA, 19-24 May 1996. Technomic Publishing, Lancaster, PA, pp. 353-373]. Initial concerns for imports of aquacultural products from developing to industrialized countries focussed on bacterial contamination [Buras, N. 1993. Microbial safety of produce from wastewater-fed aquaculture. In: Pullin, R.V.C., Rosenthal, H., MacLean, J.L.(Eds.), Proceedings of ICLARM Conferences, vol. 31, pp. 285-295]. Today, if trade opportunities are to be maintained, these countries must adapt to a full array of regulations and standards. This paper describes four scenarios in aquaculture and fishing product trade between developing countries and countries in the European Union.     

Changes in seafood consumer preference patterns and associated changes in risk exposure

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.     

Altered energy flow pathways in a lake ecosystem following manipulation of fish community structure

We used carbon and nitrogen stable isotope analyses to assess the relative contributions from pelagic and littoral energy sources to higher trophic levels in a lake ecosystem before and after a major food web perturbation. The food web structure of the lake was altered when the population sizes of the most abundant fish species (small perch, roach and bream) were reduced during an attempt to improve water quality by biomanipulation. Fish removal was followed by dense year classes of young fish, which subsequently increased the utilisation of pelagic resources. This was reflected as a decrease in relative energy contribution from littoral sources and also led to more distinct pelagic and littoral food chains after fish removal. Community metrics calculated from stable isotope data indicated increased trophic diversity and occupied niche area, and reduced trophic redundancy in the food web. However, only minor changes were observed in fish trophic positions, although roach and pike occupied slightly lower trophic positions after fish removal. Despite the Jyväsjärvi ecosystem becoming more dependent on pelagic energy after fish removals, the littoral energy contribution was still substantial, particularly to certain fish species. Hence, our results support recent arguments for the importance of benthic production in lake ecosystems. More generally, our results illustrate how large-scale perturbations of food web structure can alter energy flow patterns through an entire ecosystem.     

In-stream water quality,invertebrate and fish community health across a gradient of dairy farming prevalence in a New Zealand river catchment

Dairying is an intensive form of agriculture influencing stream ecosystems worldwide via increased levels of nutrients, deposited fine sediment and other contaminants. However, it is not fully understood how dairy farming affects food supply for stream fish. We investigated relationships between dairy farming prevalence in the catchments of nine tributaries of a New Zealand river (0% to 79% of the catchment area) and fish and invertebrate communities. Streams were sampled four times at monthly intervals for brown trout density, fitness/growth-related trout response variables, native fish density, invertebrate community metrics as well as physical and chemical water quality variables. Densities of both brown trout and native fish declined as dairying increased, with no trout found in streams where dairy farms covered more than 50% of the catchment area. Increasing dairy farming prevalence was also associated with higher in-stream levels of dissolved nutrients and deposited fine sediment. These findings suggest that increasing the extent of dairy farming in New Zealand based on practices at the time of sampling results in less abundant and diverse fish communities.     

南海油气资源潜力及勘探现状

南海的油气资源极为丰富,享有“第二个波斯湾”的美誉.南海地貌类型多样,地形复杂,其战略位置极为重要,是东亚及相邻各国必经之路.资源之争,使得周边各国使出浑身解数,发展海洋经济与技术,1981年至2002年,越南就从南沙海域的油田中开采了1亿吨石油、15亿多立方米的天然气,获利250亿美元,南海石油已成为越南国民经济的第一大支柱产业.近半世纪中国南海油气勘探工作取得巨大的成就,发现了26个新生代盆地,取得了南海海域的基本石油地质成果,为南海的勘探开发奠定了基础.南海具有巨大的勘探空间及技术发展空间,每一次的技术进步,都会带来南海油气勘探的质的飞跃.     

Oligotrophication from wetland epuration alters the riverine trophic network and carrying capacity for fish

Submerged aquatic vegetation (SAV) constitutes a major component of fish habitat, providing support for epiphytes and invertebrates as well as shelter from predators. The effects of wetland epuration from a mesotrophic to a nearly oligotrophic state were examined over a 15?km long reach of the St. Lawrence River under the direct influence of major farmland tributaries. We hypothesized that the nutrient-enriched zone would support a higher biomass of SAV, epiphytes, macroinvertebrates and fish than the nitrogen-deficient epurated zone located downstream of the wetland. Predictions included that the enriched habitat would support a richer fish assemblage, with higher biomass and growth of juvenile yellow perch than found in the epurated zone. Results supported these hypotheses, demonstrating the chain of effects of nutrient reduction on the biomass of SAV (fourfold drop), invertebrate prey (ninefold), small (threefold) and large (1.5-fold) fish between the two zones. In addition to the reduction in SAV biomass, the replacement of filamentous chlorophytes by benthic mats of filamentous cyanobacteria in the epurated zone resulted in a less complex 3-D habitat structure and a low invertebrate availability for fish. Oligotrophication by wetland epuration exerted negative effects on fish habitat quality, food quantity and availability, with an impairment of juvenile perch growth and recruitment. A generalized model of the changes in habitat carrying capacity occurring with epuration (oligotrophication) or eutrophication is presented, with examples of other aquatic systems in which strong linkages between trophic status, SAV, invertebrates and fish productivity were also demonstrated.     

Eutrophic waters,algal bloom and fish kill in fish farming areas in Bolinao,Pangasinan, Philippines

The coastal waters of Bolinao, Pangasinan, Philippines experienced environmental changes over a 10-year period (1995–2005), the most significant effect of which was the major fish kill event in 2002 that coincided with the first reported Philippine bloom of a dinoflagellate Prorocentrum minimum. Days before the bloom, dissolved oxygen was <2.0 mg/l in the waters that were stratified. These conditions may be linked to the uncontrolled proliferation of fish pens and cages to more than double the allowable limit of 544 units for Bolinao waters. Mariculture activities release organic matter from unconsumed feed and fecal material that accumulate in the water and sediments. In over 10 years, water quality conditions have become eutrophic with ammonia increasing by 56%, nitrite by 35%, nitrate by 90%, and phosphate by 67%. The addition of more fish pens and cages placed additional stress to this poorly flushed, shallow area that affected water quality due to changes in the water residence time.     

Eutrophic waters, algal bloom and fish kill in fish farming areas in Bolinao, Pangasinan, Philippines

The coastal waters of Bolinao, Pangasinan, Philippines experienced environmental changes over a 10-year period (1995-2005), the most significant effect of which was the major fish kill event in 2002 that coincided with the first reported Philippine bloom of a dinoflagellate Prorocentrum minimum. Days before the bloom, dissolved oxygen was < 2.0 mg/l in the waters that were stratified. These conditions may be linked to the uncontrolled proliferation of fish pens and cages to more than double the allowable limit of 544 units for Bolinao waters. Mariculture activities release organic matter from unconsumed feed and fecal material that accumulate in the water and sediments. In over 10 years, water quality conditions have become eutrophic with ammonia increasing by 56%, nitrite by 35%, nitrate by 90%, and phosphate by 67%. The addition of more fish pens and cages placed additional stress to this poorly flushed, shallow area that affected water quality due to changes in the water residence time.     

1999年9月21日台湾7.6级地震及台湾的地震研究工作

１９９９年９月２１日台湾省南投发生７．６级地震,造成重大财产损失和人员伤亡,台湾全岛大范围停电,火车停驶,通讯、公路、航运中断,股市和汇市停市,许多学校和单位停课或停止上班,水库大坝断裂,强余震不断,震灾区上百处起火。本文对这次地震的灾害特点、救灾和国际援助情况、地震构造、对及台湾的地震研究和观测、主要研究机构等进行了全面综述。     

梯级水坝胁迫下东江鱼类产卵场现状分析

东江作为珠江流域重要支流之一,是香港地区以及珠江三角洲东部地区重要水源.鱼类不仅是河流生态系统重要组成也是其健康状况的重要指示生物.目前东江已经修建了一系列水坝,基于东江河流生态系统健康维持和管理的需要,有必要了解河流中鱼类产卵场的现状.据此,2010年3-10月对东江古竹江段的鱼苗(卵)进行了连续采集,目前鱼苗种类已鉴定到26种(属),主要优势种类为鰕鯱(63.0%)、赤眼鳟(16.8%)、尼罗罗非鱼(9.7%)、大眼鳜(2.0%)等;调查期间古竹江段鱼苗(卵)径流量初步估算为11.4×108尾(颗),东江鱼类主要繁殖期为4-9月.与东江历史资料及西江江段鱼类繁殖现状相比较,东江鱼类产卵场功能极度退化,不仅鱼类产卵规模已明显下降,并且东江古竹江段鱼苗中洄游性种类缺失;本次调查证明东江龙川江段原有的四大家鱼产卵场已经消失;通过典范对应分析分析表明,东江江段鱼类产卵繁殖对水文生态因子的响应程度较低,说明东江江段水文节律受梯级水坝影响程度大,偏离了鱼类产卵繁殖的生态需求.尼罗罗非鱼在东江古竹江段有暴发性繁殖现象,东江已经面临外来种的严峻威胁,分析认为梯级水坝的修建是导致罗非鱼暴发性增长的主要原因之一.根据目前东江鱼类产卵场现状,建议把鲢、鳙及广东鲂列入增殖放流的品种目录,加强人工增殖放流;从贯通鱼类洄游通道及修复产卵场的需求上考虑,建议在东江各水坝上补建鱼类过鱼通道.     

2001年上半年全世界地震灾情综述

2001年1－6月全世界发生的较重大灾害地震共计8次，地震共计造成17759人死亡，953人失踪，15．9万人受伤，经济损失约163．3亿美元。重大灾害地震发生在印度。     

The Haitian housing dilemma: can sustainability and hazard-resilience be achieved?

The present danger in the Haitian rebuilding efforts, outside of the extreme level of need that often encourages temporary solutions at the expense of long-term capacity building, centers on the assumption that sustainability and resilience are mutually exclusive. They cannot be if this rare opportunity to achieve meaningful long-term change within a country that has suffered for far too long is to be fully seized. This change can be realized only with appropriate policies and incentives that do not simply fund the re-implementation of vulnerable construction modes in an effort to meet immediate needs, but that foster the introduction of alternative structural systems with the requirement that they build genuine local capacity to deliver sustainable and resilient homes that meet Haiti’s cultural and economic constraints. This short communication reviews the important housing dilemma Haiti now faces, a dilemma with international extensions since researchers and construction firms from all over the world (including France, Germany, Italy, Greece, Japan, Canada, US) are involved, and presents thoughts for the importance of offering solutions that serve both ends of the economic spectrum, are hazard-resilient and truly sustainable.     

From compliance to environmental leadership

Management systems should have control, be it financially, in relation to the human resources of a company, or in matters concerning quality, safety and the environment. Integrated management systems are required for the quality, safety and environmental areas. The converse to this is that problems are often the result of inadequate management programmes, standards and/or compliance with standards. Recent surveys have concluded that, firstly, in order to improve environmental performance, management issues need to be addressed and developed; and secondly, that the implementation of policies and measures is vital to improve environmental performance. In addition to environmental awareness among management and the need for environmental management, this paper focuses on the role of European legislation, international standardization, other international guidelines and important aspects of environmental management and auditing. Finally, it introduces a new environmental management and audit system—the international environmental rating system (IERS), which has been developed by Det Norske Veritas. IERS is a tool to guide implementation, maintenance and improvement of environmental management in industry and to measure the quality and effectiveness of environmental management. It consists of a structured management and audit protocol with good management practices and associated user guidelines.     

1999年全世界地震灾害综述

1999年全球地震活动为中等水平 ,但地震灾情较重。重大地震灾害分别发生在土耳其、中国台湾省和哥伦比亚。地震死亡人数总计 2 3 3 11人 ,伤 64 2 91人 ,经济损失约 3 0 0亿美元。台湾 7.6级地震是中国自唐山地震以来最严重的震灾。     

2006年国外灾害地震综述

2006年地震活动水平和地震灾害程度均低于往年.地震活动总量相当于过去百年期间平均值的50～70%.外电报道比较有影响的灾害地震19次,死亡超过6900人,伤超过4万人.伤亡人数相当于过去百年期间年平均的37%.较大灾害地震6次.有2次在印度尼西亚,1次在伊朗,1次在夏威夷群岛,中国台湾1次"双震",破坏海底光缆,国际通讯联络一时中断,是世界少有的地震破坏海底光缆事件.     

Hydraulic modelling of fish habitat in urban rivers during high flows

In urban rivers, flow regime and channel morphology are the drivers of physical habitat quality for aquatic species. Peak discharges are increased at high flows as a result of impermeable catchments and channel engineering for flood protection schemes. Hazardous conditions and flashy hydrographs mean that measurement of velocities at high flows is a difficult task. This research uses a three‐dimensional computational fluid dynamics (3D‐CFD) model to simulate hydraulic patterns in two urban river channels. A 3D‐CFD code, called SSIIM, was used to simulate hydraulic conditions in two engineered river reaches of the River Tame, Birmingham, UK. These two sites represent channels with different levels of engineering. Models were calibrated and tested using field measurements. Results show that modelled water surface levels and velocity profiles are well simulated. Calibrated roughness heights are compared with those derived from field measurement of sediment size. Numerical experiments are used to assess the relationship between grid resolution in the vertical dimension and the form of the modelled velocity profiles. Biologists have used laboratory experiments to determine maximum sustainable swimming speeds (MSSS) of fish, often in order to assess what level of a particular pollutant may be tolerable. In this work, simulations of high‐flow hydraulic patterns are used to compare velocity patterns with fish MSSS. Results show that when the water levels rise to fill the first channel of the two‐stage channels at the sites, which occurred 16 times in 2000, MSSS are surpassed in the majority of available habitat, suggesting that excessive velocities at high flows are one factor that limits fish habitat. A comparison between the two reaches shows that there is less available habitat in the more modified reach. Conclusions suggest that an approach that integrates water quality issues and physical channel characteristics must be taken in river rehabilitation schemes, as improvements to water quality alone may not be sufficient to improve habitat quality to the desired level. Copyright © 2002 John Wiley & Sons, Ltd.     

Environmental management of marine fish culture in Hong Kong

Marine fish farming is an important commercial practice in Hong Kong. Marine fish farms located in eutrophic coastal waters often face the threat of severe dissolved oxygen depletion associated with algal blooms and red tides. On the other hand, mariculture activities also contribute to pollution. The sustainable management of mariculture requires proper siting of the fish farms and stocking density control. Both of these are related to the carrying capacity of the water body concerned, which is mainly governed by its flushing characteristics. A simple method to determine the carrying capacity of a fish farm has been developed by using three-dimensional (3D) hydrodynamic modelling and its effective coupling with a diagenetic water quality model. A systematic methodology using numerical tracer experiments has been developed to compute the tidal flushing in a fish farm. The flushing time is determined from the results of a numerical tracer experiment using robust 3D hydrodynamic and mass transport models. A unit tracer concentration is initially prescribed inside the region of interest and zero elsewhere; the subsequent mass transport and the mass removal process are then tracked. The fish farms are usually situated in well-sheltered shallow embayments and may not connect directly to the open water. It is found that it is necessary to define both "local" and "system-wide" flushing times to represent the effectiveness of the mass exchange with the surrounding water body and the open sea respectively. A diagenetic water quality model simulating the sediment-water-pollutant interaction is employed to address the response of the water column and the benthic layer to pollution discharges. With the flushing rate reliably computed, the carrying capacity of the fish farm can be determined in terms of key water quality parameters: chlorophyll-a, dissolved oxygen, organic nitrogen and potential lowest dissolved oxygen level on a day of negligible photosynthetic production. The predictions are well-supported by field data.     

Larval fish assemblages in a tropical mangrove estuary and adjacent coastal waters: Offshore-inshore flux of marine and estuarine species

A total of 92,934 fish larvae representing 19 families were sampled monthly from the Sangga Kecil estuary (Matang Mangrove Forest Reserve) and adjacent coastal waters from May 2002 to October 2003. Larval fish assemblages were numerically dominated by Gobiidae (50.1%) and Engraulidae (38.4%). Canonical Correspondence Analysis (CCA) revealed that the larval fish assemblages, including their ontogenetic stages, differed between the mangrove estuary and adjacent offshore waters, and that salinity, turbidity and zooplankton food are the major environmental factors structuring the larval fish assemblages. Estuarine preflexion gobiid larvae were ubiquitous in the coastal and estuarine waters. Larval stages of euryhaline species that were spawned in offshore waters, such as Engraulidae and Clupeidae, were largely advected into mangrove areas at the postflexion stages. Larvae of other euryhaline fishes (Sciaenidae, Blenniidae and Cynoglossidae) that may have been spawned inside the estuary were, however, exported to offshore waters. Given that the collective number of juvenile and adult fish families in the Matang estuary was 53, while the number of larval families was only 17, the former is quite disconnected from the existing larval fish population in the estuary.