APPENDIX A5.1
GLOSSARY FOR FISHERIES IMPACT ASSESSMENT
Ardeid Species of birds of the Family Ardeidae, consisting of mainly herons, egrets and bitterns.
Bund Embankment
around the perimeter of the pond.
Detritus Material
produced by disintegration of plants and animals bodies following death and
decomposition. Also refers to
materials formed by erosion, e.g.
sand, gravel and silt.
Draining Management
practice employed in aquaculture that involves draining water out of ponds
using either a pump or sluice gate to assist in aggregating fish in high
densities to facilitate harvesting.
Ecological Value The
contribution of a habitat in sustaining the wildlife communities and essential
ecological processes of a wider ecosystem.
Fish-cum-Duck The
simultaneous raising of carp integrated with duck farming. This integrated
approach utilises the manure and excreta originated from the ducks as organic
fertilisers to enhance the productivity of the systems.
Food web The
inter-connected chains of food intake within an ecosystem.
Hetertrophic Organisms
that obtain nourishment from
organic substances.
Monoculture An
aquaculture system where one species of fish is reared in each pond, typical
species include Catfish, Seabass and Snake head.
Phytoplankton Microscopic
marine or fresh water plants (phytoplankton) that drift within the water
column, and undertake primary productivity in aquatic ecosystems.
Plankton Microscopic
marine or fresh water plants (phytoplankton) or animals (zooplankton) that
drift within the water column.
Polyculture Entails
the rearing of more than one species within a single pond at one time. This
aquaculture techniques contributes to 96.5% of the total area of active fish
ponds in Hong Kong during 1994.
Species Biologically
species is a group of organisms
that can potentially interbreed to produce fertile offspring. In practice, species may be recognised
by their similar morphology.
Tilapia An
omnivorous fish that consumes detritus and plankton, reared as a commercial
species and as considered as a trash fish.
Trash Fish Fish
that inhabit commercial fish ponds but are not of commercial value, typical
species include: Mosquito Fish, Pawn, Tilapia.
Trophic Pertaining
to the trophic level of food webs.