Phototoxicity of pyrene and benzo[a]pyrene to embryo-larval stages of the Pacific oyster Crassostrea gigas

There is a growing body of evidence to suggest that certain polycyclic aromatic hydrocarbons (PAHs) pose a greater hazard to aquatic organisms than previously demonstrated, due to their potential to cause photo-induced toxicity when exposed to ultraviolet (UV) radiation. The consequences of photo-induced toxicity are reported here for embryo-larval stages of the pacific oyster Crassostrea gigas, following exposure to pyrene and benzo[a]pyrene. During laboratory investigations, significant increases in toxicity were observed in the presence of environmentally attainable levels of UV-radiation, compared with embryos exposed to PAH alone, at levels previously deemed to have little acute biological effect. The phototoxicity of pyrene and benzo[a]pyrene completely inhibited the development to the D-shell larval stage when embryos were simultaneously exposed to 5 microg l(-1) PAH and ultraviolet light (UVB = 6.3 +/- 0.1 microW/cm2 and UVA = 456.2 +/- 55 microW/cm2). A linear relationship was also demonstrated for benzo[a]pyrene phototoxicity with decreasing UV light intensity.     

Time domain modelling of the transient asymmetric flooding of Ro-Ro ships

This work aims at contributing to improve knowledge on transient asymmetric flooding through theoretical and experimental research. First, a time domain theoretical model of ship motions and flooding is described. Results from experimental work are presented evidencing that transient asymmetric flooding may cause the capsizing of a Ro-Ro shaped barge. The theoretical model is used to predict the capsize of the Ro-Ro shaped barge. Reasonable agreement between experimental and theoretical results was found. Finally, a review of the European Gateway accident is given and the theoretical model is applied to the study of this type of accident. The conclusion is that this theoretical model, together with an accurate modelling of the flooding of machinery compartments, reproduces successfully the capsizing of the European Gateway due to transient asymmetric flooding. Therefore, the internal arrangement of Ro-Ro ships should be carefully studied at the design stage in order to avoid this phenomenon.     

The Current System in the Yellow and East China Seas

During the 1990s, our knowledge and understanding of the current system in the Yellow and East China Seas have grown significantly due primarily to new technologies for measuring surface currents and making high-resolution three-dimensional numerical model calculations. One of the most important new findings in this decade is direct evidence of the northward current west of Kyushu provided by satellite-tracked surface drifters. In the East China Sea shelf region, these recent studies indicate that in winter the Tsushima Warm Current has a single source, the Kuroshio Branch Current in the west of Kyushu, which transports a mixture of Kuroshio Water and Changjiang River Diluted Water northward. In summer the surface Tsushima Warm Current has multiple sources, i.e., the Taiwan Warm Current, the Kuroshio Branch Current to the north of Taiwan, and the Kuroshio Branch Current west of Kyushu. The summer surface circulation pattern in the East China Sea shelf region changes year-to-year corresponding to interannual variations in Changjiang River discharge. Questions concerning the Yellow Sea Warm Current, the Chinese Coastal Current in the Yellow Sea, the current field southwest of Kyushu, and the deep circulation in the Okinawa Trough remain to be addressed in the next decade. This revised version was published online in August 2006 with corrections to the Cover Date.     

Mapping Submerged Aquatic Vegetation with GIS in the Caloosahatchee Estuary: Evaluation of Different Interpolation Methods

This article evaluates different spatial interpolation methods for mapping submerged aquatic vegetation (SAV) in the Caloosahatchee Estuary, Florida. Data used for interpolation were collected by the Submersed Aquatic Vegetation Early Warning System (SAVEWS). The system consists of hydro-acoustic equipment, which operates from a slow-moving boat and records bottom depth, seagrass height, and seagrass density. This information is coupled with geographic location coordinates from a Global Positioning System (GPS) and stored together in digital files, representing SAV status at points along transect lines. Adequate spatial interpolation is needed to present the SAV information, including density, height, and water depth, as spatially continuous data for mapping and for comparison between seasons and years. Interpolation methods examined in this study include ordinary kriging with five different semivariance models combined with a variable number of neighboring points, the inverse distance weighted (IDW) method with different parameters, and the triangulated irregular network (TIN) method with linear and quintic options. Interpolation results were compared with survey data at selected calibration transects to examine the suitability of different interpolation methods. Suitability was quantified by the determination coefficient (R2) and the root-mean-square error (RMSE) between interpolated and observed values. The most suitable interpolation method was identified as the one yielding the highest R2 value and/or the lowest RMSE value. For different geographic conditions, seasons, and SAV parameters, different interpolation methods were recommended. This study identified that kriging was more suitable than the IDW or TIN method for spatial interpolation of all SAV parameters measured. It also suggested that transect data with irregular spatial distribution patterns such as SAV parameters are sensitive to interpolation methods. An inappropriate interpolation method such as TIN can lead to erroneous spatial representation of the SAV status. With a functional geographic system and adequate computing power, the evaluation and selection of interpolation methods can be automated and quantitative, leading to a more efficient and accurate decision.     

Dynamic-Stochastic Modeling of Natural Processes

We propose a method for the construction of dynamic-stochastic models of natural systems based on the assimilation of the data of observations in the prognostic equations of coupled processes. In these models, the method of adaptive balance of causes is used to deduce evolutionary equations of the analyzed processes and assimilate the data of observations in these equations. The deduced general equations are considered for an example of a marine ecosystem characterized by the development of four coupled processes. It is shown that the optimal prediction of these processes requires the solution of 11 systems of equations with simultaneous adaptation of prognostic estimates and the coefficients of the models to the data of observations. A numerical simulation experiment explaining the algorithm of the proposed method of modeling is considered. A conclusion is made that the application of this method in the geoinformation systems of monitoring of the environment is quite promising.__________Translated from Morskoi Gidrofizicheskii Zhurnal, No. 6, pp. 31–42, November–December, 2004.     

The next few years of the ICES Journal of Marine Science

This issue marks a change in the editorial team of the ICESJournal of Marine Science, in that we have bid farewell to ourformer Editor-in-Chief, Niels Daan, after six years of sterlingservice, and to our Elsevier Publishing Editor, Andrew Richford,after an even longer period of years. Both deserve credit fortheir energy and vision that has left us the legacy of a journalas widely read and cited as the ICES Journal now is, but theyleave a gap that will be a huge challenge for us to meet. However,in my new capacity as Editor-in-Chief and in Els Bosma's capacityas Elsevier's Publishing Editor, I