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C. E. Gibson
Journal (Water Pollution Control Federation)
Vol. 43, No. 12 (Dec., 1971), pp. 2436-2440
Published by: Water Environment Federation
Stable URL: http://www.jstor.org/stable/25037257
Page Count: 5
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A factor is usually said to be not limiting to growth if, when it is increased, no effect on growth is observed. Several difficulties with this definition are introduced by variations in availability for uptake of a given element, nutrient loading, effect of timing of discharges of nutrients, and changes in seasonal conditions. An ideal laboratory medium for measuring limiting levels of nutrients has not yet been developed. The influence of past history of cells on phosphorus uptake and the fixation of nitrogen by blue-green algae contribute to uncertainty. More sophisticated bioassay methods are being developed.
Journal (Water Pollution Control Federation) © 1971 Water Environment Federation