[biofilms & biodiversity]

Glossary and References


  • Abiotic - The physical and chemical non-living factors in an environment.

  • Annelids - A phylum that includes segmented terrestrial and aquatic worms.

  • Bacteria - Single celled prokaryotic organisms that form the first layer of a biofilm.

  • Biodiversity - The number of different species of organisms in a particular environment.

  • Biofilm - A coating or covering on the surface of a living or nonliving substrate composed of organisms like bacteria, protozoa, algae, and invertebrate animals.

  • Biotic - The living factors in an environment.

  • Crustaceans - A class of arthropod with 10 legs, antennae, and a hard exoskeleton.

  • Cnidaria - An animal phylum that includes hydra, sea anemones, jellyfish, and hydrozoan colonies.

  • Entoprocta - An animal phylum that includes organisms with tentacles on a cup shaped body supported by a single stalk.

  • Evenness (E) - A measure of how similar the abundances of different species are in the community.

  • Larvae - Immature forms of organisms, that typically look different from the fully grown adult and are usually smaller than the adult or even microscopic.

  • Mollusks - An animal phylum that includes bivalves ( mussels), snails, slugs, and nudibranches.

  • Nematoda - An animal phylum that includes all roundworms.

  • Phytoplankton - Drifting microscopic plants that trap the energy from the sunlight and are primary organisms in a marine food chain.

  • Platyhelminthes - A phylum of animal that includes all flatworms.

  • Protozoa - A Kingdom that includes only single celled organisms like amoeba, stentor, vorticella, colonial ciliates, etc.

  • Rotifers - A phylum that includes organisms that have ciliated mouths and a retractable "foot" for anchoring.

  • Shannon-Weiner index (H) - This diversity measure came from information theory and measures the order (or disorder) observed within a particular system. In ecological studies, this order is characterized by the number of individuals observed for each species in the sample plot (e.g., biofilm on a plexiglass disc).

  • Simpson's index (D) - The probability that two randomly selected individuals in the community belong to the same category (e.g., species).

  • Simpson's index of diversity (1 - D) - The probability that two randomly selected individuals in a community belong to different categories (e.g., species).

  • Simpson's reciprocal index (1/D) - The number of equally common categories (e.g., species) that will produce the observed Simpson's index.

  • Species - Organisms that are genetically related, similar physically, and can reproduce viable offspring.

  • Species Richness - The number of different species found in a particular environment.

  • Sessile - Organisms that remain attached to a substrate.

  • Zooplankton - Microscopic aquatic organisms, including larvae, which are the first consumers in a marine food chain.

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  • Krebs, C. J. 1989. Ecological methodology. Harper and Row, Publishers. New York. 654 pp.

  • Hill, M. O. 1973. Diversity and evenness: a unifying notation and its consequences. Ecology 54:427-432.

  • Odum, E.P. 1971. Fundatmental of ecology. W. B. Saunders Company, Publishers. Philadelphia. 574 pp.

  • Odum, E.P. 1975. Ecology: The link between the natural and the social sciences. Holt, Rinehart and Winston, Publishers. New York. 244 pp.

  • Peet, R. K. 1974. The measurement of species diversity. Annual. Rev. Ecol. Syst. 5:285-307.

  • Simpson, E. H. 1949. Measurement of diversity. Nature 163:688.

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