Animations
Movies
Words
Appendix
Summary
Art
Art
Chapter
54
Quizzes:
Self
Activities
Chapter
Cum.
Unit 8: Ecology
Ecosystems
Review
An
ecosystem
consists of all the organisms in a
, and all the abiotic factors with which they interact.
Energy
through ecosystems, while
matter
within
them.
Energy entering an ecosystem is
converted
to
energy by primary
; the total amount of energy converted is called
primary production (GPP). Some of that energy is used by the producers for
; the remaining energy available to consumers is called
primary production (
NPP
).
In aquatic ecosystems, production is mostly confined to the
zone,
where the
nutrient are often
or
, or
sometimes
.
production is the amount of energy in consumers' food that is
converted
to their own
, and can be represented in a
pyramid
of
.
In most
ecosystems,
this low trophic efficiency is also reflected in a
pyramid
of
. Most ecosystems also show a
pyramid
of
. Some ecosystems show
biomass pyramids due to
rapid
of producers.
Chemicals released by humans can become
in successive trophic levels in a process called
magnification,
becoming toxic to higher level consumers.
The
chemical
that serve as life's nutrients occur in limited quantities, and
between
and
reservoirs
of
ecosystems.
The
cycle
is driven by solar energy on a global scale.
The
cycle
reflects the reciprocal processes of
and cellular
.
Review.
The
cycle
involves local cycles between organisms and soil or water.
Review.
The
cycle
is relatively localized.
(detritivores) play a key role in the general pattern of
biogeochemical
cycling.
Large-scale agriculture removes
from the soil; excess fertilizer added to the soil can runoff into streams, and together with
discharge, can
lead
to
, excessive algal growth in aquatic
ecosystems.
Combustion of
fuels
releases excess
and
into the atmosphere, forming
and
acid and causing
precipitation.
Burning fossil fuels also releases excess levels of
carbon
into the atmosphere, which is associated with global
due to the
effect.
The release of
(CFCs) and other chlorine-containing
chemicals
has resulted in
depletion; a thinning of the
ozone
layer which protects life on Earth from
(UV) radiation.
How Does Acid Precipitation Affect Trees?
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Nov 18, 2006
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