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Bioassay experiment to assess DON bioavailability, Sawtooth Mountains, ID
A student prepares a large-scale bioassay experiment to assess the bioavailability of dissolved organic nitrogen (DON) for phytoplankton. Each bottle contains water from different DON sources and various nutrients. The growth of the phytoplankton was assessed at 2-day intervals for 14 days. Bull Trout Lake, Sawtooth Mountains, Idaho, USA. Photo, July 2006.