GLOSSARY OF TERMS 315
anadromous: species that migrate from estuarine or marine areas into freshwater to spawn.
anthropogenic: relating to, or resulting from the influences of human beings on nature.
barrier island: an island located in close proximity to the mainland, but between it and the open ocean or
sea; often composed of shifting sands and forming a barrier to tidal surges from storms that would otherwise
damage the mainland.
benthic: relating to, or of the bottom surfaces of water.
biodiversity: the variability among living organisms on the earth, including the variability within and
between species and within and between ecosystems.
bog: wetland ecosystem characterized by acidic conditions, the accumulation of peat and dominance of
sphagnum moss.
bottomland: low-lying alluvial land near a river.
by-catch: the portion of fishing catch that is discarded as unwanted or commercially unusable.
canopy: a forest's upper-most stratum; consists of a network of branches and leaves and forms a covering
that blocks sunlight from lower plants.
channelization: the modification of a channel by clearing, excavation, realignment, lining, or other means to
increase its capacity for water flow.
clearcutting: the removal of all the trees on a site for the purpose of utilization and to provide for
regeneration of an even-aged stand of trees, usually of a species requiring full sunlight for proper
development and growth.
community: collectively, all of the organisms inhabiting a common environment and interacting with each
other and their environment.