The effects of eutrophication and acidification on the ecophysiology of Ulva pertusa Kjellman

In coastal environments, acidification and eutrophication affect the physiology of marine macroalgae. We investigated the responses of Ulva pertusa Kjellman (Ulvales, Chlorophyta) under such conditions. Samples were cultured at two different pH settings (low, 7.5; high, 8.0) and at three different ammonium levels (low, 4; medium, 60; high, 120 μM NH 4 + ). Our objective was to analyze the influence that elevated CO 2 and NH 4 + might have on pH, oxygen evolution, rates of nutrient uptake, chlorophyll fluorescence, growth, and C/N ratio of that organism. Variability in pH value was enhanced under low pH/high NH 4 + and was significantly different ( p