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Urea concentrations measured in the pelagic waters of Lake Kinneret over a 12‐month period varied from undetectable to maximum values of 80 and 150 µg N liter−1, with a seasonal pattern of fluctuation. Although urea is not a major constituent of the dissolved organic nitrogen, it may provide a significant source of available nitrogen for lake phytoplankton.
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T. Berman (1974) studied this question.
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