Determining Parameters of the Numerical Response
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D.J.S. Montagnes [1] [2] ; J.A. Berges [1]
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[1] University of Liverpool
University of Liverpool
Reino Unido
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[2] University of Wisconsin–Milwaukee
University of Wisconsin–Milwaukee
City of Milwaukee, Estados Unidos
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- Localización: Microbial ecology, ISSN-e 1432-184X, ISSN 0095-3628, Vol. 48, Nº. 1, 2004, págs. 139-144
- Idioma: inglés
- Texto completo no disponible (Saber más ...)
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Resumen
The numerical response, the change in specific growth rate with food concentration, is a fundamental component of many aquatic microbial studies. Accurately and precisely determining the parameters of this response is essential to obtain useful data for both aut- and synecological studies. In this work we emphasize four points that are often ignored in designing numerical response experiments: (1) the inclusion of subthreshold concentrations (i.e., where growth rate is negative) in the experimental design; (2) an appropriate allocation of effort, i.e., the superiority of choosing more individual prey concentrations rather than replicating fewer; (3) the potential superiority of replicating experiments rather than simply replicating treatment in a single experiment; and (4) the placement of most measurements near the lower end of the concentration gradient, well below the asymptote, possibly following a geometric progression. We illustrate the first point by examining a small subset of published data on planktonic oligotrich ciliates and then, using a Monte Carlo simulation, rigorously evaluate the experimental design, supporting the remaining points.
