Survey: Bioremediation contractors guarantee performance

Experience with bioremediation technology has enabled bioremediation contractors to offer performance-based contracts for many types of bioremediation projects. This development is significant because it alleviates the previous concern with the technology regarding its lack of success at certain sites. Environmental Strategies Corporation, an independent environmental consulting firm with no financial interest in bioremediation technology, conducted an independent survey to identify bioremediation contractors that are willing to enter into performance-based bioremediation contracts. This article discusses the background of treating contaminated soil and groundwater using bioremediation and describes how a performance-based contract can be structured. The survey's format and results are then presented and analyzed. Finally, several case studies of successful bioremediation projects are presented.     

New perspectives in ecotoxicology

The task of regulating potentially harmful chemicals in the environment is presently hindered by the lack of appropriate concepts and methods for evaluating the effects of anthropogenic chemicals on ecosystems. Toxicity tests at the molecular and physiological levels have been used successfully as indicators of adverse effects on test organisms and have been extrapolated to humans to establish a basis for risk assessment. However, laboratory measurements of effects upon individuals do not translate readily into potential effects upon natural populations, in part because natural populations interact with other populations and with the physical environment. Even more difficult to assess are the deleterious impacts of anthropogenic chemicals on ecosystems, because of effects on species interactions, diversity, nutrient cycling, productivity, climatic changes, and other processes.Effects on ecosystems resulting from chemical stresses are outside the realm of classical toxicology, and an ecosystem-level perspective is essential for the consideration of such effects; but the science that deals with ecosystem-level effects,ecotoxicology, is still developing. This article synthesizes the topics discussed at a workshop on ecotoxicology held by the Ecosystems Research Center at Cornell University. Topics covered include: the regulatory framework in which ecotoxicological research must be applied; ecosystem modification of toxicant fate and transport; how ecosystem composition, structure, and function are influenced by chemicals; methods currently available for predicting the effects of chemicals at the ecosystem level; and recommendations on research needs to enhance the state of the science of ecotoxicology.     

Contextual influences on national level flood risk communication

With high profile flooding events and increasing risk and probable damages of flooding in the future flood risk management (FRM) in England and Wales has undergone substantial changes over the last decade. The contextual influences on flood risk communication in the areas of flood forecasting, warning and response, spatial planning and development control and flood insurance at a national level are investigated in this paper. Research is based on qualitative interviews with 21 representatives of key organisations and activities at a national level of FRM. Drawing on communication theory the research highlights the key contextual features at play: the characteristics of communication flow through organisations, the importance of policy as a communication tool informed and constrained by flood events, organisational agendas, communication approaches and the development of knowledge and technology. The paper describes the influence of clear policy guidance on activities in certain government FRM communication initiatives and the commercial imperative driving the insurance industry activities.     

Modelling of long-term behaviour of caesium and strontium radionuclides in the Arctic environment and human exposure

In this paper a compartment model of the highly vulnerable Arctic terrestrial food chain "lichen-reindeer-man" is outlined. Based upon an analysis of measured (137)Cs and (90)Sr contents in lichen and reindeer meat from 1961 up to 2001, site specific model parameters for two regions in north-western Arctic Russia and for Kautokeino municipality in Arctic Norway have been determined. The dynamics of radionuclide activity concentrations in the "lichen-reindeer-man" food chain for all areas was satisfactorily described by a double exponential function with short-term and long-term effective ecological half-lives between 1-2 and 10-12 years, respectively, for both (137)Cs and (90)Sr. Using parameter values derived from the model, life-time internal effective doses due to consumption of reindeer meat by reindeer-breeders after an assumed single pulse deposit of 1 kBq m(-2) of (137)Cs were estimated to be 11.4 mSv (Kola Peninsula), 5 mSv (Nenets Autonomous Area), and 2 mSv (Kautokeino, Norway). Differences in vulnerability to radiocaesium deposition were due to differences in transfer between lichen and reindeer and in diet between the three regions.     

Long-term trends in Swiss rivers sampled continuously over 39 years reflect changes in geochemical processes and pollution

Environmental Science and Pollution Research - Long-term changes of 14 water constituents measured in continuously and water discharge proportionally collected samples of four Swiss rivers over a...     

Predicting the Vulnerability of Tropical Reef Fishes to Exploitation with Phylogenies and Life Histories

Abstract: Fishing has led to local extirpations of reef fishes. For conservation and management purposes, it is important to identify all those species that are vulnerable to fishing, but this cannot be done using a priori assessments or by describing trends in abundance because the necessary scientific resources are not available. Thus the predictions of vulnerability that provide the basis for conservation action will have to be made with existing data or data that can be acquired rapidly before further extirpations occur. The life histories of species may determine their responses to exploitation, and we describe how an easily measured parameter, maximum observed size, is related to population trends of exploited fishes on coral reefs. Using a phylogenetic comparative approach, we demonstrated that species of grouper (Epinephelinae), snapper (Lutjanidae), and parrotfish (Scaridae) that decreased in abundance more than their nearest phylogenetic relative had greater maximum size. Our results suggest that one can predict the vulnerability of reef fishes to exploitation based on responses of their relatives. The quality of the prediction was good for the intensively fished groupers and snappers but poor for the lightly fished parrotfishes. Our approach may help proactive conservationists and fishery managers identify and conserve vulnerable species in new, developing, or lightly exploited fisheries, thereby reducing their reliance on reactive management methods.