(1)
Plant community: An assemblage
or association of certain dominant indicator species occupying a given region.
In California,
the desert biome consists of several different plant communities such as the
creosote such scrub, shadscale scrub, sagebrush scrub, Joshua tree woodland.
The local chaparral and coastal sage scrub plant communities surrounding Palomar
college are considered part of an arid desert biome. Some general biology text
books have added a seventh biome
called the shrub land biome to encompass these
brushy habitats.
(2).
Chaparral: A plant
community composed of dense, impenetrable, shrubby vegetation adapted to a
Mediterranean climate with winter-wet and summer-dry seasons. The plant
community is well- developed in the mountains of San Diego country, following periodic brush
fires, many of the shrub species resprout from subterranean lignotubers.
(3).
Coastal sage scrub: A plant community similar to the chaparral,
but typically found at lower elevations (generally below 2, 000 feet). Like the
chaparral, many of the shrub species resprout from subterranean lignotubers. It
is dominated by aromatic coastal sagebrush (Artemisia Californica) and is
common in the hills bordering Palomar
College. Unfortunately,
this plant community is prime land for developers and is rapidly being replaced
by housing developments in San Diego
country. It is now (2001) considered to be an endangered (threatened) plant
community in Southern California.
(4).
Ecosystem: All of the organisms in a natural community or
biome plus all of the associated environmental factors with which they
interact. The term ecosystem could actually be applied to any of the
terrestrial biomes or plant communities. For examples, the tundra biome could
also be referred to as tundra ecosystem, the chaparral plant community could
also be referred to as the chaparral ecosystem. The term ecosystem is
well-suited for aquatic communities such as ponds, lakes, streams and even the
ocean. In fact, oceanography is the study of ocean ecosystem. Including ocean,
topsoil and atmosphere, the earth is a large, complex ecosystem called the
biosphere, however, in terms of the vast universes it is but a mere dot. A
self-contained space ship in which gasses and waste are recycled may also be
thought of an ecosystem.
(5)
Biosphere: (Earth
Ecosystem), The zone of atmosphere, land and water at the surface of the earth
occupied by living things. In grave danger by the effects of humans including
overpopulation, pollution and exploitation.
(6)
Environment: The sum total
of physical and biotic factors that surround an organism or population of
organisms.
(7)
Ecology: The study of
the enter relationships between plants and animals and their environment. The
term environment includes the sum total of physical and biotic conditions, and
influence that surround an organisms or population of organisms.