+

Option G:

Ecology and

Conservation

BY: Lunch Box, Spike, Weezy, Reckless, Zorro, Lucy Goosy, Ray Ray, Mad Dog.

+G1 Community Ecology

+G.1.1 Outline the factors that affect the distribution of plant species, including temperature, water, light, soil pH, salinity andmineral 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.

Light is important for photosynthesis but too much can lead to water loss.

Soil pH can affect nutrient uptake from the soil.

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. Temperature: Many organisms are specifically adapted to

specific temperatures.

Water: Some species need more water than others, and their water needs limit where they can exist.

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.

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. 1.Make a Quadrat (1 meter by 1 meter wooden square)

2.Lay the quadrat on the ground, and count how many of a given species of plant are in it.

3.Continue to do this in random places in the area you want to sample

4.Find an average of plants per quadrat using these samples.

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.

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. 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. Competition is when two species are attempting to occupy

the same niche, or compete for the same resources.

Herbivory interactions are when a species of animal eats a species of plants.

Predation is between one consumer and another, and involving one species killing the other for food.

Parasitism is an interspecial relationship characterized by one species benefiting and another species being harmed, though typically not killed, unlike predatory relationships.

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 Competition Examples:

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.

Herbivory examples: cows eating grass and zooplankton eating phytoplankton

Predatory Examples: bears eating salmon and wolves eating deer

Parasitism Examples: humans and tapeworms and ponderosa pines and mistletoe.

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.

a proposition which states that two species competing for the same resources cannot coexist if other ecological factors are constant.

- 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.

Fundamental

1. 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

1. 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

The mass of living biological organisms in a given area or ecosystem at a given time.

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.

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. 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.

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.

GROSS PRODUCTION: the total energy or nutrients assimilated by an organism, a population, or an entire community.

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.

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.

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.

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 ofeach.

Primary succession occurs after a disturbance that leaves no soil

An example is a cooled lava flow

Primary succession occurs slowly

Secondary succession occurs after a disturbance that leaves the soil intact

An example is a forest fire

Secondary succession can occur very rapidly

+G.2.7 Outline the changes in species diversity and production during primary succession.

Species diversity is very low in the early stages of primary succession

This is because few species can tolerate the barren conditions

However, as primary succession continues, species diversity increases

Gross Production is also very low in the early stages of primary succession but increases during primary succession

This is because small plants are replaced by larger plants with more leaf surface area to photosynthesize

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.

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

Biome – type of ecosystem with similar temperature, rainfall and dominant flora and fauna.

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 Simpsonindex.

+G.3.3 Discuss reasons for the conservation of biodiversity using rainforests as anexample.

Economic Reasons new commodities, material,

and medicine can be found tourism of the rainforest

(ecotourism)

+G.3.3 Discuss reasons for the conservation of biodiversity using rainforests as anexample. CONTINUED.

Ecological Reason Fixes large amounts of

CO2 without increasing

greenhouse effect and

greenhouse gases Soil erosion and flooding

changes in weather

patterns

+G.3.3 Discuss reasons for the conservation of biodiversity using rainforests as anexample. CONTINUED.

Ethical Every species has the right to life Cultural important to indigenous people

+G.3.3 Discuss reasons for the conservation of biodiversity using rainforests as anexample. CONTINUED.

Aesthetic Beautiful species Inspiration to writers,

poets and

painters.

+G.3.4 list three examples of introduction of alien species that have had significant impacts on ecosystems.

Floating fern – takes over lakes, aquarium or pond plant.

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.

Cain toads in Australia

+G.3.5 Discuss the impacts of alien species on ecosystems.

Increase in the introduction of alien species has several side effects Crowd-out of native species.

Ex: Zebra mussels vs native mussels Predation

Ex: Snails over-eating tomatoes

+G.3.6 Outline one example of biological control of invasive species.

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.

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.

Cause: When pollutants are amplified, such as spraying large amounts of DDT to kill insects.

Consequence: Contamination of surrounding areas and beyond when animals eat contaminated material.

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.

UV radiation can penetrate living cells and damage DNA ( can cause cancer and mutation)

Disrupts  the productivity of the ecosystems by damaging and even killing some organisms.

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.

Reduces ozone layer by destroying it 

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.

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.

The population of indicator species increases or decrease significantly depending on changes in their environment.

Indices are accurate indicator of environmental changes.

Calculated via the number of tolerant and intolerant at a specific time.

Organisms in the indicator species can be monitored over time.

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.

Javan Tiger of Indonesia became extinct around 1976.

Factors that contributed to their extirpation include: Dramatic increase of human population in 1900s;

deforestation eliminated the Javan tigers’ habitats. The tigers and their prey were poisoned in many places. 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.

Government institutions that establish nature reserves usually decide on the following features: Whether to create a large reserve or small

reserve Whether to have one large undivided reserve,

or separate small reserves. 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.

Active management techniques in conservation include: Captive breeding and relocation

Habitat protection and restoration

Re-vegetation of cleared forests

Reintroduction of threatened species into an environment

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).

In-situ conservation are usually “on-site conservation”, meaning the process of protection within a species’ natural habitat or cleaning up the habitat itself.

Can also include a species defending themselves from unwanted predators.

The advantages of this process include: Creates ideal habitat for species under threat

Establishes sustainability in the population

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.

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 K-strategies.

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, post-environmental change

+G.5.1 Distinguish between r-strategies and K-strategies. 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, long-established 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.

Study Catches:

1. 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.