Foraging habitats of the seabird community of Europa Island (Mozambique Channel)

We investigated the foraging habitats of the winter breeding community of tropical seabirds from Europa Island (Mozambique Channel) in September 2003. We focused our study on the dominant species of this austral community, the sooty tern (Sterna fuscata), the red-footed booby (Sula sula), and the frigatebirds, including the great (Fregata minor) and the lesser frigatebirds (F. ariel). We considered the at-sea distribution and abundance of these species in relation to chlorophyll concentration, sea-surface temperatures, sea-surface height anomalies, depth of the thermocline, distance to the colony, and presence of surface marine predators, flying fishes and other seabirds. Although the marine environment where seabirds foraged was oligotrophic, it presents the best feeding opportunities for seabirds for the area in winter. Our study demonstrates that the winter-breeding seabird species of Europa Island tend to forage in productive waters in association with other marine predators when possible. Sooty terns and frigatebirds were widely distributed in the whole study area, whereas red-footed boobies were not found farther than 160 km from their colonies and were associated with relatively productive waters. Sooty terns and red-footed boobies were aggregated where flying fishes were abundant. The presence of other marine predators was associated with larger multispecies feeding flocks than when no association occurred. Sooty terns, which are numerically dominant at Europa and adopted network foraging, seem to be catalysts of feeding events, and represented a good target for the other foraging species, especially frigatebirds. However, when possible, frigatebirds favour association with flocks of red-footed boobies.Communicated by S.A. Poulet, Roscoff     

Observations sur le développement larvaire de Nyctiphanes couchii (Crustacea: Euphausiacea) au laboratoire

Larvae of Nyctiphanes couchii (Bell) were reared in the laboratory from the second and third calyptopis stages; they were fed animal, algal and mixed diets. Data are presented on larval morphology, growth and moulting rates. It is demonstrated that N. couchii is capable of filter-feeding and of capturing prey from the calyptopis phase onwards. The influence of diet on larval development is discussed: algal diets induce a slower growth rate than that achieved by feeding with Artemia salina nauplii alone, and increase the length of intermoult periods and of ontogenesis. A limited supply of A. salina nauplii has similar effects.     

Cadmium and zinc bioaccumulation and metallothionein response in two freshwater bivalves (Corbicula fluminea and Dreissena polymorpha) transplanted along a polymetallic gradient

This study was designed to compare the metallothionein (MT) response capacity of two freshwater bivalves, Corbicula fluminea and Dreissena polymorpha, along an environmental gradient of polymetallic pollution. The bivalves were transplanted into 4 stations in southwestern France, with a cadmium and zinc pollution gradient. MT and metal concentrations were measured in the soft bodies of the clams and mussels over 2.5 months. In the zebra mussels, variations in MT concentrations were strictly correlated to progressive Cd and Zn bioaccumulation. In contrast, the faster response in the clams appeared positively correlated to Cd accumulation only, with the activation of efficient detoxification mechanisms which limited Cd bioaccumulation and reduced Zn concentrations over time. Nevertheless, despite stronger metal accumulation factors in D. polymorpha, C. fluminea revealed higher sensitivity of MT response along the pollution gradient.     

EPR monitoring of the bioavailability of an organic xenobiotic (4-hydroxy-TEMPO) in model clay suspensions and pastes

Electron paramagnetic resonance spectroscopy is used to monitor the bioavailability of a nitroxide spin probe, 4-hydroxy-Tempo or Tempol, in Ca-hectorite suspensions and pastes, to bacteria capable of degrading this probe co-metabolically. In nutrient solutions with an initial probe concentration of 1.2 mM and in the absence of hectorite, bacteria are able to denature Tempol and eliminate its paramagnetic signal within 48 h. In the presence of hectorite and after flocculation, the effect of bacteria is significantly delayed, but almost complete denaturation still occurs, after roughly 120 h. When hectorite is added but the bacterial/clay suspension is not centrifuged, Tempol denaturation levels off after about 24 h and reaches a plateau with approximately 45% of Tempol remaining. This plateau does not constitute evidence of limited bioavailability, as is widely assumed, since subsequent addition of nutrients causes the denaturation reaction to proceed to a second plateau, with merely 10% of Tempol remaining.     

北京市危险化学品安全生产技术支撑体系建设

1引言 近年来,在北京市委、市政府的领导下,各职能部门的协同努力下,北京市危险化学品安全生产工作取得了显著成绩,制定了一系列危险化学品安全生产管理规范,开展了危险化学品从业单位安全质量标准化活动,进一步提高了从业单位的安全生产管理水平,我市危险化学品安全生产状况总体趋向好转.     

Assessment of ecotoxicological risks related to depositing dredged materials from canals in northern France on soil

The implementation of an ecological risk assessment framework is presented for dredged material deposits on soil close to a canal and groundwater, and tested with sediment samples from canals in northern France. This framework includes two steps: a simplified risk assessment based on contaminant concentrations and a detailed risk assessment based on toxicity bioassays and column leaching tests. The tested framework includes three related assumptions: (a) effects on plants (Lolium perenne L.), (b) effects on aquatic organisms (Escherichia coli, Pseudokirchneriella subcapitata, Ceriodaphnia dubia, and Xenopus laevis) and (c) effects on groundwater contamination. Several exposure conditions were tested using standardised bioassays. According to the specific dredged material tested, the three assumptions were more or less discriminatory, soil and groundwater pollution being the most sensitive. Several aspects of the assessment procedure must now be improved, in particular assessment endpoint design for risks to ecosystems (e.g., integration of pollutant bioaccumulation), bioassay protocols and column leaching test design.     

Radiological Dispersion Devices: are we prepared?

Already before the events of September 11th 2001 concern was raised about the spread of orphan sources and their potential use in Radiological Dispersion Devices by terrorist groups. Although most of the simulated scenarios foresee a rather limited direct health impact on the population, the affected region would suffer from the indirect consequences such as social disruption, cleanup requirements and economic costs. The nature of such a radiological attack would anyway be different compared to conventional radiological accidents, basically because it can happen anywhere at any time. Part of the response resides in a general preparedness scheme incorporating attacks with Radiological Dispersion Devices. Training of different potential intervention teams is essential. The response would consist of a prioritised list of actions adapted to the circumstances. As the psychosocial dimension of the crisis could be worse than the purely radiological one, an adapted communication strategy with the public aspect would be a key issue.     

中心商业区环境安全管理与控制

城市中心商业区环境安全的管理与控制是城市诸多问题中的热点.通过分析中心商业区的环境空气质量和环境噪声、防火防爆设施及应急装备、人流车流秩序、公共卫生系统,提出了在城市中心商业区环境安全的管理与控制中应执行的相关标准,设立了相关部门和管理措施.对中心商业区环境安全控制的规制化具有一定积极意义.     

Towards a constructivist program in safety

This paper delves into the relationship between safety and constructivism. In the past 30 years, the constructivist discourse has become very popular but also controversial as it challenges some key categories associated with modernity, such as reason, objectivity, truth and reality. In the safety literature, several works advocate its use. This paper has three objectives. The first one is to reveal the existence of a constructivist discourse in the field of safety. It does this by bringing together scattered pieces of works from different authors who endorse and apply to various topics a position labelled as constructivist. However, and that is the paper’s second objective; it demonstrates that there is not only one constructivism, but several. In order to ground this contention, the paper proceeds with a multidisciplinary and historical approach. It is then argued that it is more appropriate not to conflate this diversity of constructivisms. The paper looks for a solution to this problem by providing a classification based on two groups of parameters: mild/strong and cognitive/social, defining four types. This step serves the third objective which consists in initiating a multifaceted constructivist program in safety composed of heterogeneous but related empirical and theoretical areas of investigations.