Nutrient demand and availability among planktonic communities — an attempt to assess nutrient limitation to plant growth in 12 central volcanic plateau lakes

Abstract Four assays of nitrogen demand and 3 for phosphorus were employed in 12 lakes at 4 seasons in an attempt to identify the nutrients limiting plankton growth. Orthophosphate turnover times, chlorophyll, and a range of analyses for nitrogen and phosphorus were made in support of the bioassays. Consideration was given to both statistical and biological interpretation of the assays. It was not possible to identify with certainty the limiting nutrients from this information, but criteria were developed which allowed conclusions to be drawn about plankton nutrient sufficiency. Differential storage capacity relative to subsistence cell quota for the 2 nutrients needs to be considered when interpreting the bioassays.