MarinePollutionBulletin culture and Fisheries have shown levels of up to 320 ppm to be present in the blubber of porpoises. Human populations are less at risk due to their varied diet though communities in which fish is an important dietary component may be affected. Other leading scientists have agreed that the problem must be solved before the quantity of PCBs reaches a critical level. Although Dr John Harwood, Director of the Marine Mammal Research Unit in Cambridge warns that the prediction by Professor Cummins that marine mammals will be extinct in 50 years is a little alarmist, he agrees that there should be a concentrated effort to collect and dispose of PCBs in an ecologicallysound manner in an effort to put a halt to the current situation. PCBs contained in generators and insulating fluid are being released into the atmosphere when electrical equipment which has reached the end of its useful life is carelessly dumped. It has been estimated that 98% of the PCBs currently entering the seas do so via the atmosphere and the remaining 2% through river runoff.
Dutch Ocean Incineration Ban Challenoed The Netherland's recent ban on the incineration of toxic waste at sea has been attacked by several European companies as being an unwise step to take if attempting to reduce environmental pollution. The North Sea States agreed to ban ocean incineration in 1994 at the last meeting of the London Dumping Convention (see Mar. Pollut, Bull. 19, 648). An agreement to reduce marine incineration by 65% by 1991 was also made then by the member countries (the UK, Netherlands, France, Belgium, West Germany, Denmark, Sweden, and Norway). After a Dutch Parliament vote however, the Netherlands brought forward the date of the ban and stopped issuing incineration permits in August of this year. The nine companies challenging the Dutch decision have gone to the Netherlands' highest court of appeal where they have argued that there are not enough land-based incineration plans to cope with the
The boundaries of the proposed nature reserve have yet to be drawn up but it is likely that the United States contribution to the venture will be a large part of the Nome peninsula, known as the Bering Land Bridge National Preserve. The Soviet Union currently has a series of designated ecologically-protected zones but is thought to be examining this scheme with a view to making it more like the American and British national park system.
Global w a r m i n g : Hots Up
the Pace
Present computer models of the progression of the greenhouse effect may prove to be inaccurate in the light of a recently discovered factor known as the phytoplankton multiplier, according to Dr John Woods, Director of the Natural Environment Research Council. Dr Woods advised the British Association for the Advancement of Science that, since phytoplankton absorbs vast quantities of carbon dioxide during growth, a decline in phytoplankton growth would drastically impair the ability of the oceans to absorb carbon dioxide. Present models are based on the assumption that the oceans will continue to absorb 50% of the extra CO2 produced by burning fossil fuels and tropical rainforests. However, global warming would appear to inhibit plankton growth, thus accelerating the greenhouse effect many times. Dr Woods presented evidence published earlier this year which indicated that global warming at the end of the last ice age caused a change in ocean turbulence. Phytoplankton tend to grow mostly in spring when they remain in the surface waters (nearest to sunlight) due to the relatively stable ocean currents at this time of the year. Any change in turbulence pattern could therefore disrupt plankton growth. The effects of the phytoplankton multiplier is believed to have led to an increase in atmospheric temperatures of 7°C in just 50 years at the end of the last ice age. H I L L A R Y CROWE
additional waste.
North American News
Arctic Wilderness Park
Hydrothermal Vent Communities Found in Lake
The Exxon Valdez disaster has prompted the United States and Soviet Union to work together on plans for an Arctic wilderness reserve. With further oil exploration taking place off Alaska's Barrow Peninsula and the USSR beginning to drill in its own Arctic coastal zone, concern over the effects of oil pollution has united US and Soviet ecologists. Scientists from both countries are planning joint research programmes into animal migration patterns and breeding zones in Soviet Siberia and US Alaska, areas which are ecologically similar but separated by the 130 km wide Bering Strait. It makes ecological sense that, in spite of the political barrier formed by the Bering Strait, the region should be jointly managed as a single ecosystem,,
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Scientists investigating Crater Lake in Oregon have discovered communities that resemble the deepwater hydrothermal vent communities found in oceans. Crater Lake lies in a 10 km wide and nearly 914 m deep caldera that was formed by the collapse of the now dormant Mount Mazama in the Cascade mountains. Mount Mazama forms part of the Pacific Ocean 'Ring of Fire', and is evidence of the magma chambers that still underlie the Cascades. These magma chambers are fueled by the subduction of the Juan de Fuca and Gorda Plates under the North American Plate. Oregon State University scientists have been studying Crater Lake via submersible for the past two