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Significantly higher concentrations of nitrate and silicate were found in glaciated South Cape Fiord than in unglaciated Grise Fiord, in the Canadian Arctic, or in adjacent Jones Sound. No significant differences in phosphate concentrations were found. Glacial activity apparently enriches the concentrations of those nutrients most critically limiting for arctic phytoplankton requirements.

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ABSTRACT. Individual transferable quotas (ITQs) have become a popular management tool for fisheries. They have been promoted in some quarters and seriously criticized in others because of their social and economic impacts. A more serious problem is that ITQs provide exclusive access to public resources presumably in return for some public benefit, namely conservation; however, in a high percentage of cases they do not conserve fish stocks. In this article, we focus on the reasons that ITQs do not conserve stocks. We point to a number of phenomena identified in the literature as affecting stocks of fish, including problems with total allowable catch (TAC), ecological hierarchy theory, r and K species, the Allee effect, scale and metapopulation structure, the need to have selective gear, and the continuation of roving bandit incentives. Despite their growing popularity with managers, ITQs do not solve any of these problems. We argue there may be better ways to manage. One possibility is what we call parametric management.

New estimates of production of sub-ice and ice microalgae in the shelf seas of the Canadian Arctic and in the Canada Basin of the Arctic Ocean derived from reduction of nitrates in the water column, as recorded in time series available in publicly held data bases, suggest that it is of greater magnitude (up to 30 g C m -2 year -1 ) and represent a higher proportion (up to 50 % on the shelf and 90 % in the Canada Basin) of net community production than previously estimated for both areas.

Reviews investigations 1961-1963 into chlorophyll concentrations in sea ice in both arctic and antarctic regions. Results are compared with own researches off Devon Island, Canada, which are reported in detail. Chlorophyll a and c concentrations were obtained from underside of ice by a 7.5 cm diam ice corer and light penetration was measured by freezing a photometer into the ice; readings of both are tabulated. Chlorophyll values exceed concentrations in open sea water. The values were found to fall with increased light, and the high ratio of c to a is interpreted as a adaptation for maximum absorption of blue light through ice and snow. The algae are associated mainly with young ice peripheral to the Arctic Ocean. As a primary production resource, an estimated volume of 25 X 10*6 kg of chlorophyll a for a two-month for the arctic region is considered conservative.

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