GLOSSARY G5
all species, not just for us. Our success depends
on learning how the earth sustains itself and
integrating such environmental wisdom into
the ways we think and act. Compare deep ecology
worldview, frontier worldview, planetary management
worldview, stewardship worldview.
environmental worldview Set of assump-
tions and beliefs about how people think the
world works, what they think their role in the
world should be, and what they believe is right
and wrong environmental behavior (environ-
mental ethics). See deep ecology worldview, environ-
mental wisdom worldview, frontier worldview, plan-
etary management worldview, stewardship worldview.
EPA U.S. Environmental Protection Agency;
responsible for managing federal efforts to con-
trol air and water pollution, radiation and pesti-
cide hazards, environmental research, hazardous
waste, and solid waste disposal.
epiphyte Plant that uses its roots to attach
itself to branches high in trees, especially in
tropical forests.
erosion Process or group of processes by
which loose or consolidated earth materials are
dissolved, loosened, or worn away and removed
from one place and deposited in another. See
weathering.
estuary Partially enclosed coastal area at the
mouth of a river where its fresh water, carrying
fertile silt and runoff from the land, mixes with
salty seawater.
eukaryotic cell Cell that is surrounded by a
membrane and has a distinct nucleus. Compare
prokaryotic cell.
euphotic zone Upper layer of a body of water
through which sunlight can penetrate and sup-
port photosynthesis.
eutrophication Physical, chemical, and
biological changes that take place after a
lake, estuary, or slow-fl owing stream receives
inputs of plant nutrients—mostly nitrates and
phosphates—from natural erosion and runoff
from the surrounding land basin. See cultural
eutrophication.
eutrophic lake Lake with a large or excessive
supply of plant nutrients, mostly nitrates
and phosphates. Compare mesotrophic lake,
oligotrophic lake.
evaporation Conversion of a liquid into a gas.
evergreen plants Plants that keep some of
their leaves or needles throughout the year.
Examples include cone-bearing trees (conifers)
such as fi rs, spruces, pines, redwoods, and
sequoias. Compare deciduous plants, succulent
plants.
evolution Seebiological evolution.
exhaustible resource Seenonrenewable
resource.
exotic species Seenonnative species.
experiment Procedure a scientist uses
to study some phenomenon under known
conditions. Scientists conduct some experi-
ments in the laboratory and others in nature.
The resulting scientifi c data or facts must be
verifi ed or confi rmed by repeated observations
and measurements, ideally by several different
investigators.
exponential growth Growth in which some
quantity, such as population size or economic
output, increases at a constant rate per unit of
time. An example is the growth sequence 2,
4, 8, 16, 32, 64, and so on, which increases by
100% at each interval. When the increase in
quantity over time is plotted, this type of growth
yields a curve shaped like the letter J. Compare
linear growth.
extinction Complete disappearance of a
species from the earth. It happens when a spe-
cies cannot adapt and successfully reproduce
under new environmental conditions or when
a species evolves into one or more new species.
Comparespeciation. See also endangered species,
mass extinction, threatened species.
extinction rate Percentage or number of
species that go extinct within a certain time such
as a year.family planning Providing information, clini-
cal services, and contraceptives to help people
choose the number and spacing of children they
want to have.
famine Widespread malnutrition and starva-
tion in a particular area because of a shortage
of food, usually caused by drought, war, fl ood,
earthquake, or other catastrophic events that
disrupt food production and distribution.
feedback Any process that increases (positive
feedback) or decreases (negative feedback) a
change to a system.
feedback loop Occurs when an output of
matter, energy, or information is fed back into
the system as an input and leads to changes in
that system. See positive feedback loop and negative
feedback loop.
fermentation Seeanaerobic respiration.
fertility rate Number of children born to an
average woman in a population during her life-
time. Compare replacement-level fertility.
fi rst law of thermodynamics In any physi-
cal or chemical change, no detectable amount of
energy is created or destroyed, but energy can
be changed from one form to another; you can-
not get more energy out of something than you
put in; in terms of energy quantity, you cannot
get something for nothing. This law does not
apply to nuclear changes, in which energy can
be produced from small amounts of matter. See
second law of thermodynamics.
fi shery Concentration of particular aquatic
species suitable for commercial harvesting in a
given ocean area or inland body of water.
fi shprint Area of ocean needed to sustain the
consumption of an average person, a nation, or
the world. Compare ecological footprint.
fl oodplain Flat valley fl oor next to a stream
channel. For legal purposes, the term often
applies to any low area that has the potential
for fl ooding, including certain coastal areas.fl ows Seethroughputs.
fl yway Generally fi xed route along which
waterfowl migrate from one area to another at
certain seasons of the year.
food chain Series of organisms in which each
eats or decomposes the preceding one. Compare
food web.
food web Complex network of many inter-
connected food chains and feeding relationships.
Comparefood chain.
forest Biome with enough average annual
precipitation to support the growth of tree spe-
cies and smaller forms of vegetation. Compare
desert, grassland.
fossil fuel Products of partial or complete
decomposition of plants and animals; occurs
as crude oil, coal, natural gas, or heavy oils as
a result of exposure to heat and pressure in he
earth’s crust over millions of years. See coal,
crude oil, natural gas.
fossils Skeletons, bones, shells, body parts,
leaves, seeds, or impressions of such items that
provide recognizable evidence of organisms that
lived long ago.
foundation species Species that plays a ma-
jor role in shaping a community by creating and
enhancing a habitat that benefi ts other species.
Compareindicator species, keystone species, native
species, nonnative species.free-access resource Seeopen access renewable
resource.
freons Seechlorofl uorocarbons.
freshwater life zones Aquatic systems where
water with a dissolved salt concentration of less
than 1% by volume accumulates on or fl ows
through the surfaces of terrestrial biomes.
Examples include standing (lentic) bodies of
fresh water such as lakes, ponds, and inland
wetlands and fl owing (lotic) systems such as
streams and rivers. Compare biome.front The boundary between two air masses
with different temperatures and densities. See
cold front, warm front.
frontier science Seetentative science.
frontier worldview View held by European
colonists settling North America in the 1600s
that the continent had vast resources and was a
wilderness to be conquered by settlers clearing
and planting land.
functional diversity Biological and chemical
processes or functions such as energy fl ow and
matter cycling needed for the survival of species
and biological communities. See biodiversity, eco-
logical diversity, genetic diversity, species diversity.
fundamental niche Full potential range of
the physical, chemical, and biological factors a
species can use if it does not face any competi-
tion from other species. See ecological niche.
Comparerealized niche.
game species Type of wild animal that people
hunt or fi sh for, for sport and recreation and
sometimes for food.