Aw. Herman et al., INSTRUMENTS FOR MEASURING SUBICE ALGAL PROFILES AND PRODUCTIVITY IN-SITU, Canadian journal of fisheries and aquatic sciences, 50(2), 1993, pp. 359-369
Instruments have been developed for the in Situ measurement of concent
ration and productivity of bottom ice algal layers in Resolute Passage
, eastern Canadian Arctic. Measurements are accomplished by deploying
an instrument on an arm articulated remotely through a hole in the ice
, sampling the subice surface, and finally recovering the instrument a
nd sample. The first instrument is an incubation system that is used t
o measure in situ productivity of a subice core. Results show the exte
nt and range of productivity in bottom ice, with low and high biomass
at the commencement of the algal bloom and near the end of the bloom p
eriod, respectively. The second instrument is a reflectance meter that
can be used to measure chlorophyll profiles at the subice surface. Th
e meter was calibrated against measured chlorophyll concentrations of
extracted cores. After calibration the instrument can be used to measu
re integrated chlorophyll (milligrams per square metre) and profiles (
milligrams per cubic metre) rapidly and synoptically. Deployment of th
e arm coupled with a plankton pump sampler is also briefly described.