The effect of added nutrients on the periphyton of a tundra stream was tested during July and August. Flow‐through systems consisting of a bank of clear plastic tubes containing racks of microscope slides were suspended from floats in the stream. Nutrients were enriched in the experimental tubes by siphoning concentrated nutrient solutions from Mariotte bottles into the upstream end of each tube. Slides from each tube were assayed at 2–6‐day intervals for chlorophyll content and photosynthetic 14CO2 uptake. Levels of chlorophyll and CO2 uptake were significantly higher than the controls both in the tubes with 10 µg PO4‐P · liter−1 of stream water and in those with P plus 100 µg NH4NO3− N·liter−1. Nitrogen alone gave no stimulation.
No takes yet. Share an insight, caveat, or question.
Peterson et al. (1983) studied this question.