• Phosphorus metabolism of several aquatic microorganisms

      Lang, Douglas; Brown, E. J. (1980-12)
      Several taxonomically diverse aquatic microplankton were described growing at phosphorus (P) concentrations that limit growth in many natural aquatic systems. Because natural aquatic systems are subject to periodic fluctuations in P levels, both steady-state (via continuous culture) and transient (via batch culture) growth were described. Complete growth kinetic descriptions of Synechococcus Nageli (strain A) and Scenedesmus quadricauda were used to predict the relative competitive abilities of these species when P was the growth-limiting nutrient. These descriptions, coupled to their morphological characteristics, were used to construct partial physiological profiles for each organism. The profiles indicate that S. Nageli (strain A) (a small unicellular blue-green alga) is better suited for growth in P-limited oligotrophic niches than is S. quadricauda (a green alga). However, results from kinetic experiments with these and several other microplankton, show that such physiological profiles are not necessarily indicative of profiles for taxonomically related species.