Biomedical subjects

J L Arvai

Publications and source records attributed to J L Arvai.

3 recordsLinked to original sources

PubMed2002

Improvement of the sediment ecosystem following diversion of an intertidal sewage outfall at the Fraser river estuary, Canada, with emphasis on Corophium salmonis (Amphipoda).

Primary treated sewage effluent from the city of Vancouver, Canada was deposited directly onto the intertidal ecosystem of Sturgeon bank, Fraser river estuary between 1962 and 1988. In response to the degraded sediment conditions an azoic zone developed near the discharge outfall. Effluent discharges into the intertidal zone were almost completely stopped in 1988 with the construction of a submerged outfall. Our studies, conducted between 1994 and 1996, showed considerable improvement in the environment of the mudflat ecosystem, including increased dissolved oxygen, decreased sediment chlorophyll, decreased organic material in the sediment, reduced heavy metals in surficial sediment and increased grain size. The amphipod Corophium salmonis, important in the food web for juvenile salmon and other fish species, recolonized the previously azoic location. At reference stations, C. salmonis density was similar to that observed in previous surveys two decades earlier. Our data strongly suggest that improvement or sediment conditions near the former sewage outfall was a major factor enabling colonization by C. salmonis.

Amphipoda↗

PubMed2001

Print media framing of the environmental movement in a Canadian forestry debate.

In a recent paper, it was suggested that one of the reasons behind the decline in public regard toward British Columbia's environmental movement was an increasingly negative portrayal of them by the print media. To investigate this suggestion, we undertook a content analysis of print media reporting of forestry and environmental activities in the province's most widely read newspaper, the Vancouver Sun, during 1993 and 1997. We hypothesized that if the print media did contribute to the decline in public regard toward the environmental movement, we would find increasingly negative coverage of the environmental movement over the periods studied. We also hypothesized that this would be accompanied by a decrease in the frequency of articles dealing with issues consistent with the agenda of the environmental movement. We were not able to provide support for our initial hypothesis, nor did we observe a decrease in coverage emphasizing the environmental issues. We did, however, observe an increase in coverage of articles emphasizing typically proindustry issues with many more articles written with a proforestry slant in 1997 than articles written in 1993. This suggests that there had been an agenda shift from environmentally oriented concerns in British Columbia to those associated with the forest industry. As an explanation for the agenda shift, we point to changes in the management and reporting philosophy at the Vancouver Sun, the emergence of an organized, proindustry counterframing strategy by the BC Forest Alliance, and the implementation of several government policies aimed at regulating the activities of the forest industry.

British Columbia↗

PubMed2001

Testing a structured decision approach: value-focused thinking for deliberative risk communication.

Public participation is now part of many decision making processes for managing environmental and technical risks. This article describes a test of a strategy to improve the quality of public input by combining themes from risk communication with the prescriptive decision process of value-focused thinking. It was hypothesized that participating in a structured, value-focused risk communication approach would lead people to make more thoughtful, better informed, and hence higher quality decisions by helping them to consider and discuss a wider array of decision-relevant issues and address key value trade-offs. It is also anticipated that utilizing a value-focused decision structure would make participants feel more comfortable with their decisions; more satisfied that their selected alternative reflected their key concerns; and, in the end, more satisfied with their decisions. To test these hypotheses, six groups comprised of 7 to 10 people participated in conventional "alternative-focused" risk communication workshops and eight groups participated in similar "value-focused" workshops. All workshops dealt with the management of risks to riverine salmon habitat from hydroelectric electricity generation. The results provided support for the hypotheses: the value-focused decision structure led to more thoughtful and better informed risk management decisions.

Adult↗