Ecology Study Guide
Ecology –the study of the interactions
between organism and the environment

Climate- a weather condition in a certain area
Macroclimate patterns affects on
macroclimate (ex: sunlight and
temperature under a log)
Biomes- the major types of ecosystems that
occupy a large region

10 Types of Biomes
Freshwater
 low salt concentration
 littoral zone( contains rooted aquatic
plants)
 Limnetic zone (occupied by
phytoplankton)
 Oligotrophic lake(nutrient poor &
oxygen rich)
 Eutrophic lake (high nutrient & and
lower oxygen)
Marine(high salt concentration)
 Coral reef – a biome created by a
group of cnidarians
Biotic Factors- a living component
Ex: insect, worm, and a dog
Abiotic component- the nonliving
chemical and physical components
Ex: sun, soil, and water
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Savannas
Desert
Chaparral
 dominated by dense evergreen
shrubs
Temperate Grass land
Temperate Broadleaf forest
 a lot of deciduous trees
Coniferous forest
Tundra
Tropical Forest
Demography- the study of vital statistics of a
population, especially birth and death rates
Population Dispersion
 The pattern of spacing among
individuals within the boundaries of the
population
a) Clusterd/Clump
b) Random
c) Uniform
Population Ecology
Population- a group of individuals living
in a same area
Influences
 Density- the # of individuals per
unit area or volume
 Distribution size
 Age structure of populations
Exponential Growth
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Rate of population growth stays the
same , as a result the population size
increases steadily
No carrying capacity
Aquatic Biome
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Ecology Study Guide
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The equation
for
exponential
growth is :
dN/dt=rN
J-Shaped curve is
the population size
growing
exponentially
increases in a
constant rate
Logistic Population Growth

Involves exponential growth when a
population is small and a steady
decrease in growth in time as the
population approaches the carrying
capacity
Formula for
logistic
DN/Dt=rN(K-N)/K
growth:
 Carrying Capacity determined by
many factors:
a) Completion
b) Immigration
c) Emigration
d) Catastrophic events
Can be used to explain demographic
patterns
Density Dependent factors-regulates
population growth
 Completion for resources
 Territoriality( available space for
territory)
 Disease
 Predation
Density Independent- has an effect on
population size regardless of its density
S-shaped curve show how a population
becomes limited by
a density
dependent factor
(water and food)
Carrying
Capacity (K)-the
maximum size of a
population that area can support
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Community ecology
Community- is a group of population of
different species living close enough to
interact
Predation

 Natural Disasters
 Weather
Age Structure Pyramid- show the relative #
of individuals of each age in a population
Is a +/- interaction between two
species in which one specie ( the
predator) eats the other specie( the
prey)
Symbiosis- occurs when individuals of two
or more species live in direct contact with
one another
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Ecology Study Guide
Paratism- is a +/- symbiotic interaction in
which the parasite derives its nourishment
from its host
Mutualism- is an interspecific interaction that
benefits both species (+/+)
Commensalism- benefits one of the species
but neither harms or helps the other species
Trophic Structure- the feeding relationship
among the organisms
Trophic levels – the links in the trophic
structure of a community
Food Webs- consist of two or more food
chains linked together
Dominant specie- has the highest
biomass
Ecosystem and Restoration Ecology
Ecosystem
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is the sum of all organisms
living within its boundaries
involves 2 unique process:
energy flow and chemical
cycling
The flow of energy
o
Can be traced through the
trophic levels of a food chain
and food web
o
Energy cannot be recycled

Primary producer in an ecosystem are the
autotrophs( " self-feeders")Ex. Plants

Heterotrophs or consumers are the "other
feeders"

Primary Consumers - herbivores that eat
the primary consumers
Secondary Consumers- carnivores that
eat the herbivores
chemical energy by autotrophs
is known as the Gross Primary
Production(GPP)
in aquatic ecosystems it is affected
primarily by light availability and
nutrient availability
temperature and
moisture control the primary
production in terrestrial economy
GPP
Tertiary Consumers- carnivores that eat
the secondary consumers
Decomposers (Detritivores) - consumers
that get their energy from nonliving organic
material Ex: dead leaves, dead organism,
and wood
The feeding
level might
change as the
stage in a
species' life
cycle changes
Primary
Producer the
o
is not the amount of
energy available to
consumers
Net Primary Production(NPP)
is the equal gross primary production
minus the energy used by the primary
producers
o
NPP=GPP-Ra
amount of light
energy
converted to
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Eutrophic- a lake that
is nutrient rich and
supports huge amount
of algae
Evapotranspiration-a measure
amount of water transpired by
plants
Energy

energy is lost at each level of
transfer as heat
3 Types of Ecological Pyramids
o
a biomass pyramid
o
an energy pyramid
o
a pyramid of numbers
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is a balance between the amount
of CO2 removed from ecosystem
by photosynthesis and cellular
respiration
The burning of fossil fuels adds
significant amounts of Co2 to the
atmosphere
CO2 effects on global warming
Biogeochemical Cycles
 the nutrient cycles that contain
both biotic and abiotic
components
 these cycles allow scientist
how nutrient flows through
ecosystems
 MATTER CYCLES!!
 Energy does NOT CYCLE!!!!
•a common limiting factor for plant growth
•most of earth's nitrogen is in the form of
N2
•is unusable by plants
•other important nutrient cycles involve
water and phosphorous
Nitrogen Fixation- major pathway for
nitrogen to enter an ecosystem
Nitrification
Nitrogen Cycle
•the process by which ammonium (NH4+)
is oxidized by nitrate (NO3-) by bacteria
•these two chemical compounds can be
absorbed by plants
•moves nitrogen from the atmosphere
through the living world
Denitrification- bacteria releasing nitrogen
to the atmosphere
Carbon Cycle
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Ecology Study Guide
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Bioremediation- is the use of organisms
to detoxify polluted ecosystems. Ex.
Prokaryotes, fungi, or plants
Toxins become more concentrated
in successive trophic levels
Greenhouse Effect
o
Bioaugmentation- introducing species
such as nitrogen fixers to add essential
nutrients
Conservation Biology
Biodiversity- the degree of variation of life
forms within a given species and
ecosystems
Three Main Levels
1. Genetic Diversity
2. Species Diversity
3. Ecosystem Diversity

Earth is changing rapidly as a result of
human actions
Acid Precipitation
Habitat loss
Introduced specie
Overharvesting
Global change
Population conservation focuses on size,
genetic diversity, and critical habitat
Landscape and regional conservation help
sustain biodiversity
Biodiversity Hot Spot
o
burning of fossil fuels
CO2 levels are steadily increasing
a relatively small area with an
exceptional concentration of
endemic species and a large # of
endangered and threatened
species
4 Major Threats
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o
the absorption of heat the Earth
experiences
Global warming is caused by the
Ozone Layer
o
 Defined ad rain, snow, or frog with a
pH less than 5.2
 Oxides form when stuff like wood
and fossil fuels burn
The amount of UV
radiation from the sun
through the atmosphere
Biological magnification
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