Transcript Option G: Ecology and Conservation

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BY: Lunch Box, Spike, Weezy, Reckless, Zorro,
Lucy Goosy, Ray Ray, Mad Dog.
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G1 Community Ecology
+ G.1.1 Outline the factors that affect the distribution
of plant species, including temperature, water, light,
soil pH, salinity and
mineral nutrients.

Temperature: Temperature that is too high or low can lead to
damage or denaturation of enzymes.

Water: plants need water and without water will die.
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Light is important for photosynthesis but too much can lead
to water loss.
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Soil pH can affect nutrient uptake from the soil.
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High salinity can reduce the rate of osmosis or lead to water
loss in the roots

Mineral nutrients in the soil are essential for plant growth.
+ G.1.2 Explain the factors that affect the distribution
of animal species, including temperature, water,
breeding sites, food supply and territory.
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Temperature: Many organisms are specifically adapted to
specific temperatures.
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Water: Some species need more water than others, and their
water needs limit where they can exist.
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Breeding Sites: Breeding sites are essential for certain
organisms; without them they will not breed and a stable
population will not be maintained.

Food: Organisms can only exist in environments where enough
food is available.
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Territory: many organism require a given territory to exist, and
without enough territory will not be able to exist in an area.
+ G.1.3 Describe one method of random sampling,
based on quadrat methods, that is used to compare
the population size of two plant or two animal
species.
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1.Make a Quadrat (1 meter by 1 meter wooden square)
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2.Lay the quadrat on the ground, and count how many of a
given species of plant are in it.
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3.Continue to do this in random places in the area you want
to sample
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4.Find an average of plants per quadrat using these samples.
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5.Multiply this number by the number of square meters in the
total area you want to survey. This will give you an
approximate number of plants in the surveyed area.
+ G.1.4. Outline the use of a transect to correlate the
distribution of plant or animal species with an
abiotic variable.
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A transect is essentially a line that is drawn through an area
in an ecosystem. The idea behind a transect is one takes a
rope or a line and unrolls it from a given point to another
point and counts the number of each given animal or plant
species along the line. The transect can then correlate the
distribution of these species with an abiotic variable (the
terrain) because ideally, the transect will run over several
different miniature biomes, like dense forest, meadows and
marshland. Then, the list of species can be corroborated with
the changing terrain to give researcher an idea of what
species tend to live in what biomes.
+ G.1.5. Explain what is meant by the niche concept,
including an organism’s spatial habitat, its feeding
activities and its interactions with other species.
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An ecological niche is an imaginary space which represents
a given combination of environmental resources and
conditions. When an animal or plant species is said to exist in
a niche, it is exploiting those environmental resources and
conditions with its role in the environment. An organism's
spacial habitat and its interactions with other species are also
a part of its niche. For instance, a predator occupies a niche
in which its interactions with other species are characterized
mostly by predation. By contrast, a parasite's niche means
that its interaction with many species will be either
coexistence or predation, and its interaction with one or two
species will be exploitation.
+ G.1.6 Outline the following interactions between
species, giving two examples of each: competition,
herbivory, predation, parasitism, and mutualism.
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Competition is when two species are attempting to occupy
the same niche, or compete for the same resources.
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Herbivory interactions are when a species of animal eats a
species of plants.
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Predation is between one consumer and another, and
involving one species killing the other for food.
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Parasitism is an interspecial relationship characterized by
one species benefiting and another species being harmed,
though typically not killed, unlike predatory relationships.
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Mutualism is a reaction between two species characterized
by mutual benefit.
+ G.1.6 Outline the following interactions between
species, giving two examples of each: competition,
herbivory, predation, parasitism, and mutualism.
CONTINUED
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Competition Examples:
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Competition: tree species often compete with one another for sunlight
and nutrients. For instance, in the Rocky Mountains, both aspen and
pines require sunlight and the same nutrients, so both tree species
attempt to crowd the others out so they can get access to nutrients.
Another example of competition is between lions and cheetahs on the
African savannah. Both occupy the same territory and eat the same
animals, so fights between the two species are not unknown.
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Herbivory examples: cows eating grass and zooplankton eating
phytoplankton
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Predatory Examples: bears eating salmon and wolves eating deer
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Parasitism Examples: humans and tapeworms and ponderosa pines and
mistletoe.
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Mutualism Examples: the relationships between the clown fish and the
sea anenome and the goby and the pistol shrimp.
+ G.1.7 Explain the principle of competitive
exclusion.
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a proposition which states that two species competing for the
same resources cannot coexist if other ecological factors are
constant.
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- when one species has even the slightest advantage or edge
over another, then the one with the advantage will dominate
in the long term.
+ G.1.8 Distinguish between fundamental and realized
niches.
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1.
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1.
Fundamental
The full range of environmental conditions and resources
an organism can possibly occupy and use, especially when
limiting factors are absent in its habitat
Realized
The part of fundamental niche that an organism occupies
as a result of limiting factors present in its habitat.
+ G.1.8 Distinguish between fundamental and realized
niches. CONTINUED
+ G.1.9 Define biomass
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The mass of living biological organisms in a given area or
ecosystem at a given time.
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Biomass can refer to species biomass, which is the mass of
one or more species, or to community biomass, which is the
mass of all species in the community.
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Apart from bacteria, the total global live biomass has been
estimated as 560 billion tonnes, most of which is found in
forests
+ G.1.10 Describe one method for the measurement
of biomass of different trophic levels in an
ecosystem.
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To find the biomass of a trophic level, you must take all
species in that level and find the dry mass of each species, to
do that you must find a sample of each and dry it out to
release all water weight.
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After the mass is found for all, you can use methods of
sampling to find the total population of each species and
multiply that number by the value found for mass. Then add
up the products for all organisms in the trophic level, this
gives you the biomass of the level.
+
G2 Ecosystem and Biomes
+ G.2.1 Define gross production, net production, and
biomass.
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GROSS PRODUCTION: the total energy or
nutrients assimilated by an organism, a
population, or an entire community.
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NET PRODUCTION: Net primary production
(NPP) is the total energy (or nutrients)
accumulated by an ecological unit of interest
(such as an organism, a population, or an
entire community).
+ G.2.2 Calculate values for gross production and net
production using the equation: gross production –
respiration = net production. (GP – R = NP)
+ G.2.3 Discuss the difficulties of classifying
organisms into trophic levels.
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It is difficult due to the fact that some organisms can be
secondary, tertiary, and may be quaternary consumers at the
same time, such as humans. It is difficult to place them on a
certain level of the food pyramid.
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For this reason, an alternate method of classification - the
food web - has been developed. The food web displays
relationships not as a simple hierarchy but rather a complex
network, with the various feeding relationships between
species existing as connections and the animals themselves
existing as the hubs.
+ G.2.4 Explain the small biomass and low numbers of
organisms in higher trophic levels.
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There is a decreasing biomass of organisms in the higher
trophic levels because energy is lost between levels in the
form of heat (respiration), waste, and dead material. Around
10-20% of the energy proceeds on to the next trophic level.
+ G.2.5 Construct a pyramid of energy, given
appropriate information.
+ G.2.6 Distinguish between primary and secondary
succession, using an example of
each.
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Primary succession occurs after a disturbance that leaves no
soil
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An example is a cooled lava flow
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Primary succession occurs slowly
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Secondary succession occurs after a disturbance that leaves the
soil intact
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An example is a forest fire
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Secondary succession can occur very rapidly
+ G.2.7 Outline the changes in species diversity and
production during primary succession.
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Species diversity is very low in the early stages of primary
succession
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This is because few species can tolerate the barren conditions
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However, as primary succession continues, species diversity
increases
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Gross Production is also very low in the early stages of primary
succession but increases during primary succession
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This is because small plants are replaced by larger plants with
more leaf surface area to photosynthesize
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Gross production eventually stabilizes
+ G.2.8 Explain the effects of living organisms on the
abiotic environment, with reference to the changes
occurring during primary succession.
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Living organisms can help with soil development, as a plant
grows, their roots grow deeper down and break rock into
small particles, helping soil formation. Plants enrich the soil
with minerals as they die and decompose. The plant roots
hold the soil particles together, preventing soil erosion and
retain nutrients. The water that evaporates from many plant
leaves condenses and comes down in the form of rain. The
presence of organic materials in the soil and the presence of
roots and root hair help in the retention of water and slows
down drainage.
+ G.2.9 Distinguish between a biome and biosphere
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Biome – type of ecosystem with similar temperature, rainfall
and dominant flora and fauna.
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Biosphere – all of the biomes together makes up biosphere,
this is where all life can be found on the planet.
+ G.2.10 Explain how rainfall and temperature affect
the distribution of biomes.
+ G.2.11 List Characteristics of six major biomes.
+
G3 Impacts of Humans on
Ecosystems
+ G.3.1 Calculate the Simpson diversity index for two
local communities.
+ G.3.2 Analyze the biodiversity of the two local
communities using the Simpson
index.
+ G.3.3 Discuss reasons for the conservation of
biodiversity using rainforests as an
example.
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Economic Reasons
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new commodities, material,
and medicine can be found
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tourism of the rainforest
(ecotourism)
+ G.3.3 Discuss reasons for the conservation of
biodiversity using rainforests as an
example. CONTINUED.
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Ecological Reason
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Fixes large amounts of
CO2 without increasing
greenhouse effect and
greenhouse gases
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Soil erosion and flooding
changes in weather
patterns
+ G.3.3 Discuss reasons for the conservation of
biodiversity using rainforests as an
example. CONTINUED.
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Ethical
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Every species has the right to life
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Cultural important to indigenous people
+ G.3.3 Discuss reasons for the conservation of
biodiversity using rainforests as an
example. CONTINUED.
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Aesthetic
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Beautiful species
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Inspiration to writers,
poets and
painters.
+ G.3.4 list three examples of introduction of alien
species that have had significant impacts on
ecosystems.
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Floating fern – takes over lakes, aquarium or pond plant.
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3 species of rats have introduced New Zealand during the
19th century. Causes extinction of native bird species. Big
South Cape Island was rat-free until 1950 when the black
rate came took over, attacked young birds in nest even
adult birds.
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Cain toads in Australia
+ G.3.5 Discuss the impacts of alien species on
ecosystems.
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Increase in the introduction of alien species has several side
effects
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Crowd-out of native species.
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Ex: Zebra mussels vs native mussels
Predation
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Ex: Snails over-eating tomatoes
+ G.3.6 Outline one example of biological control of
invasive species.
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Floating fern was introduced into lakes in
tropic and subtropic and the number of
leaves doubles every 2 weeks. They spread
over lakes, preventing native species from
growing. It has been controlled by
introducing an alien species called salvinia
weevil to feed on the leaves.
+ G.3.7 Define biomagnification.
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The process by which chemical substances become more
concentrated at each trophic level.
+ G.3.8 Explain the cause and consequences of
biomagnification, using a named example.
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Cause: When pollutants are amplified, such as spraying large
amounts of DDT to kill insects.
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Consequence: Contamination of surrounding areas and
beyond when animals eat contaminated material.
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Ex: Cane toads in Australia – brought in to eat insects
attacking cane sugar, no predator, cane toads got out of
control and become a highly invasive species.
+ G.3.9 Outline the effects of ultraviolet (UV) radiation
on living tissues and biological productivity.
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UV radiation can penetrate living cells and damage DNA (
can cause cancer and mutation)
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Disrupts the productivity of the ecosystems by damaging
and even killing some organisms.
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Slows down growth of plants by slowing down the rate of
photosynthesis
+ G.3.10 Outline the effect of chlorofluorocarbons
(CFCs) on the ozone layer.
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Reduces ozone layer by destroying it
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Because of ozone reduction more UV radiation passes and
damages life forms in earth
+ G.3.11 State that ozone in the stratosphere absorbs
UV radiation.
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the ozone layer is limited to UV absorption in the
stratosphere.
+
G4 Conservation of Biodiversity
+ G.4.1 Explain the use of biotic indices and indicator
species in monitoring environmental change.
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The population of indicator species increases or
decrease significantly depending on changes in
their environment.
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Indices are accurate indicator of environmental
changes.
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Calculated via the number of tolerant and
intolerant at a specific time.
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Organisms in the indicator species can be
monitored over time.
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Example: sludge worms are excellent indicators of
oxygen in waterways.
+ G.4.2 Outline the factors that contributed to the
extinction or one named animal species.
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Javan Tiger of Indonesia became extinct around 1976.
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Factors that contributed to their extirpation include:
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Dramatic increase of human population in 1900s; deforestation
eliminated the Javan tigers’ habitats.
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The tigers and their prey were poisoned in many places.
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Following WWII, the forests that they inhabited also were
exploited for natural resources.
+ G.4.3 Outline the biogeographical features of nature
reserves that promote the conservation of diversity.
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Government institutions that establish nature
reserves usually decide on the following
features:
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Whether to create a large reserve or small reserve
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Whether to have one large undivided reserve, or
separate small reserves.
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Undivided reserves should contain corridors, or
ways of migrating between reserves in case of
environmental changes.
+ G.4.4 Discuss the role of active management
techniques in conservation.
 Active management is when humans intervene in the conservation
of an area to restore areas and protect native species.
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Active management techniques in conservation include:
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Captive breeding and relocation
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Habitat protection and restoration
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Re-vegetation of cleared forests
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Reintroduction of threatened species into an environment
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International agreements that prohibit the trades of endangered plant and animal species.
+ G.4.5 Discuss the advantages of in situ conservation
of endangered species (terrestrial and aquatic
nature reserves).
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In-situ conservation are usually “on-site conservation”, meaning the
process of protection within a species’ natural habitat or cleaning up
the habitat itself.
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Can also include a species defending themselves from unwanted
predators.
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The advantages of this process include:
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Creates ideal habitat for species under threat
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Establishes sustainability in the population
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Marine and terrestrial reserves don’t need to assist in this conservation method
+ G.4.6 Outline the use of ex situ conservation
measures, including captive breeding of animals,
botanic gardens and seed banks.
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
Measures “off-site conservations” to protect endangered
species of plant or animal through the removal of part of the
population from a threatened habitat. (examples: botanical
garden, zoo, seed bank)
Advantages include:
 Some species might be facing immediate extinction and need refuge.

Creates a carefully controlled environment.

Allows for rehabilitation of animals, making way for breeding.
+
G5 Population Ecology
+ G.5.1 Distinguish between r-strategies and Kstrategies.

r-Strategists
1.
Life Span: Short
2.
Growth: Small Quick
3.
Maturity: Early
4.
Offspring: Many, Once, Un-nurtured
5.
Competition: Low
6.
Environmental Conditions: Unstable, changing, postenvironmental change
+ G.5.1 Distinguish between r-strategies and Kstrategies. CONTINUED.

K-Strategists
1.
Life Span: Long
2.
Growth: Large, Slowly
3.
Maturity: Late
4.
Offspring: Few, Repeatedly, Nurtured
5.
Competition: High
6.
Environmental Conditions: Stable, established
+ G.5.2 Discuss the environmental conditions that
favour either r-strategies or K-strategies.

r-Strategists
1.
Unstable, Changing environments that provide opportunity
for fast- reproducing organisms.
2.
Early primary or secondary succession provide
opportunities for these species.
+ G.5.2 Discuss the environmental conditions that
favour either r-strategies or K-strategies.
CONTINUED

K-Strategists
1.
Stable, predictable environments is it more effective to
invest resources in becoming more competitive.
2.
Macrofauna and Flora are more abundant in stable, longestablished ecosystems and habitats after much succession
of species,
+ G.5.3 Describe one technique used to estimate the
population size of an animal species based on a
capture-mark-release-recapture method.
+ G.5.4 Describe the methods used to estimate the
size of commercial fish stocks.

1.

Study Catches:
Species/Age/Length/Breeding Conditions
Information from Fishers:
1.
Number and kinds of fish thrown back.
2.
Tag and release
3.
Perception of catch

Research Vessels:
1.
Trawling assessing random species
2.
Echolocation to monitor populations
+ G.5.5 Outline the concept of maximum sustainable
yield in the conservation of fish stocks.
+ G.5.6 Discuss international measures that would
promote the conservation of fish.