Primary-Production measurements for the green seaweed Codium fragile in long island sound

Rates of primary production and compensation depths were determined for Codium fragile by 3 different measurements: (1) growth rate; (2) rate of 14C-fixation; (3) rate of O2 evolution. The radiocarbon assay employed liquid scintillation counting of homogeneous suspensions of seaweed tissue in gelled fluor. Maximum rates of primary production ranged between 2.6 and 3.9 mg C-fixed/g dry weight/h. The compensation depth is regulated by local turbidity, as is vertical distribution. All 3 methods for the determination of compensation depth, when used simultaneously, gave the same value. Chlorophyll levels were found to vary inversely with available light, hence depth, whereas starch levels were found to vary directly with available light. © 1973 Springer-Verlag.

Duke Scholars

Author Joseph S. Ramus Marine Science and Conservation