Assimilation of Organic Matter by Zooplankton1
نویسنده
چکیده
A method for direct measurcmcnt of percentage of assimilation of organic matter by zooplankton that does not require the quantitative recovery of feces and can be adapted for USC in the field as well as in laboratory investigations is described. If it is assumed that only the organic fraction of the food ingested by a zooplankton animal is affected by the digestive process, it can be shown that percentage of utilization is defined as (F’ E’) (l-E’)(F’) x1oo’ 1 where F’ is the ash-free dry weight : dry weight ratio (fraction of organic matter) in the ingestccl food, ancl E’ is the same ratio in a reprcscntativc sample of fcccs. The mcthocl compares favorably, as a measure of assimilation, with direct measurement of the quantity of organic matter lost from foocl during passage through the digestive tract.
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