Phytoplankton Nitrogen in the Oceans
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چکیده
The ratio of cellular nitrogen and chlorophyll has been studied in cultures of marine phytoplankton during and after recovery from nitrogen deficiency. The time factors were observed to vary together; however, the ratio was only constant when the cells were sufficient in nitrogen. Since nitrogen deficiency produced chlorotic cells in all species studied, the degree of deficiency could be ascertained by measuring the ratio of carotenoid to chlorophyll a. Thus an expression utilizing the ratio of plant pigments has been formulated to compute cellular nitrogen from chlorophyll a. This pigment:nitrogcn relationship has been applied to estimate the quantity of nitrogen in natural populations of phytoplankton. The amounts of nitrogen in phytoplankton estimated from plant pigment measurements has been observed to vary between 18-70yo of the total particulate matter.
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تاریخ انتشار 1999