Biofilms and Biodiversity Glossary

Glossary

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.

Bryozoan: An animal phylum that includes various bryozoan animals, or "moss" animals that are typically colonial in organization.

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.

Polychaete worm: A marine group of annelids that are the most numerous in the phyla Polychaetes. They can be free-living or sessile, depending on their life history.

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.