SFU EVSC 100 FINAL REVIEW

The biosphere can be defined as the sum of all ____________ in an area, representing all organisms in that area as well as the physical environments in which they interact

b) ecosystems

The biosphere can be defined spatially of qualitatively. Provide both definitions. (6 pts)

Spatial Definition: everywhere on Earth where living things are found

Qualitative Definition: all of Earth's ecosystems, including all biota

Define the term "ecosystem"

An ecosystem is a specific portion of a biome consisting of the living (biotic) and non-living (abiotic) environmental components that interact

Define the term "community"

A community is all the populations (plants/animals/other species) living and interacting in an area (aka the "living" part of an ecosystem)

Biome location are determined by _________________________ but we characterize them by __________________.

1) climate and key environmental factors

2) dominant vegetation/other organisms

Name three main types of biomes

terrestrial

marine

freshwater

Terrestrial biomes are located along gradients of ____________ and ____________

1) arctic

2) tropical

?

Aquatic biomes are located along gradients of ____________ and ____________

1) freshwater

2) marine

?

Coral Reefs are found in marine locations that are ___________ and ___________, conversely, the abyssal plain is ____________ and _______________

1) warm

2) shallow

3) cold

4) deep

Tundra biome latitudes

high northern latitudes

Grassland biome latitudes

mid latitudes, interiors of continents

Desert biome latitudes

mid latitudes

Deciduous forest biome latitudes

mid latitudes

Boreal forest biome latitudes

mid-high latitudes

tropical rainforest biome latitudes

near the equator

In what climate would you find tundra biome?

very cold, harsh, long winters (short and cool summers)

10-25 cm of precipitation per year

In what climate would you find grassland biome?

cool in winter, hot in summer

25-75 cm of precipitation per year

In what climate would you find desert biome?

hot days/cool nights

less than 10 inches of precipitation per year

In what climate would you find deciduous forest biome?

mild summers and cold winters

76-127 cm of precipitation per year

In what climate would you find boreal forest biome?

very cold winters, cool summers

50 cm of precipitation

In what climate would you find tropical rainforest biome?

hot all year

200-400 cm of precipitation per year

Depth is an importation determinant of aquatic biome type. Why?

the deeper into the water, the less sunlight, therefore less temperature in the water

What kind of soil would you find in boreal forest biome?

acidic, mineral poor, decayed pine and spruce needles on surface

What kind of soil would you find in tropical rainforest biome?

nutrient poor

What kind of soil would you find in deciduous forest biome?

rich topsoil over clay

What kind of soil would you find in desert biome?

poor in animal and plant decay products but often rich in minerals

What kind of soil would you find in tundra biome?

nutrient poor, permafrost layer a few inches down

What kind of soil would you find in grassland biome?

rich topsoil

Which continent has the greatest area of desert biome?

Africa

Which continent has the greatest area of tropical rainforest biome?

South America

Which continent has the greatest area of savannah biome?

Africa

Name one freshwater and one marine biome

freshwater: lake

marine: coral reef

What is a habitat?

A habitat is the physical environment where a species typically lives

What is a niche?

A niche is the role a species plays in its ecosystem; not only its habitat requirements, but also how it acquires energy and nutrients, and how its interacts with other species/non-biotic parts of ecosystem

Environmental Gradient Diagram 3 zones

Zone of Intolerance -> Zone of Physiological Stress -> Zone of Optimum Range -> Zone of Physiological Stress -> Zone of Intolerance

What is a range of intolerance?

the range of a limiting factor within which a species can survive and reproduce

What is ecosystem production?

Ecosystem production is the amount of energy trapped by producers and converted into organize molecules (sugar) and ultimately biomass; limited by sunlight and nutrient availability

What is primary productivity?

Rate at which energy is converted by autographs into organic substances (and ultimately biomass)

What is net primary production?

amount of chemical energy left over after producers have used some for respiration; amount of energy available to higher trophic levels as biomass

What is a bottom up cascade?

a bottom up cascade is when a primary producer is removed, and there is a reduction of population size throughout the community

What is a top down cascade?

a top down cascade is a trophic cascade where a food chain or web is disrupted by the removal of a top predator

Describe an example of a top down trophic cascade.

ocean predators removed, therefore forage fish number increases ---> their food, zooplankton will have decrease in abundance, allowing their food, phytoplankton to increase in population

Name the ecosystem that covers the largest area in Canada?

Boreal forest

Where are most peatlands in Canada located?

Ontario (?)

Peatlands are important reservoirs (sinks) for what nutrient?

Peat stores organic carbon that would otherwise be released into the environment.

What is the difference between ecosystem ecology and community ecology?

Ecosystem ecology includes understanding how humans have altered ecosystems, while community ecology is the study of the biotic components of ecosystems

Name one example of an ecosystem function, and one example of an ecosystem service.

function: how species interact

service: providing habitat for species

What is an indicator species? Name one example.

An indicator species is a species that are particularly vulnerable to changed in the ecosystem, and give early warning of problems

eg: Lichen

Why are lichens considered composite organisms?

a mutualistic relationship between an alga/cyanobacteria and a fungus (?)

A species that impacts its community more than its abundance would predict, often changing the physical landscape in the process, is called a ______________. Name one example.

key stone species

beaver

What is the difference between symbiosis and mutualism?

Symbiosis is any relationship between species that is frequent/common, where are mutualism is a relationship between two species where both species benefit from their interaction with each other

How is it possible that multiple warbler species who eat the same prey insects can successfully co-exists in the same ecosystem?

The warblers engage in resource partitioning; different species of warblers forage in different areas of the tree when other are present

Define commensalism

one species benefits and the other is unaffected (flying squirrel lives in cavities made by woodpeckers)

Define parasitism

one species benefits and the other is harmed (animal with ticks will be weakened from blood loss)

Define mutualism

both species benefit (bee gains nutrition, flower gets pollinated)

Define competition

organisms that vie for the same resource are in competition with each other, the greatest competition for an individual is from a member of its own species (fighting for same resources)

Species diversity comprises two factors, name and define them both.

Species Richness: number of different species in an area

Species Evenness: the relative abundance of each species in a community

What is the difference between detrivores and decomposers?

Detrivore: organisms that feed on dead organic matter

Decomposer: organisms that break down decomposing organic matter into its basic constituent parts

What is a keystone species, name an example?

A keystone species is a species that impacts their community more than their abundance predicts

eg: beaver/ pileated woodpecker

Define the term resilience in an ecosystem context, provide a common example of perturbation.

ecosystem resilience is an ecosystems ability to tolerate/adjust toe environmental change and return to its original state (easier with greater ecosystem complexity/more niches)

perturbation: fires, human deforestation

Do upper trophic levels have higher/lower levels of species richness than lower trophic levels?

Upper trophic levels have lower species diversity as there is a decrease in energy while moving up trophic levels, therefore leading to fewer species

Differentiate between core and edge species.

Core species specialize in inner, less disturbed, more uniform areas of an ecosystem

Edge species specialize in outer edge zones, where one ecosystem meets another, and there is more variability in landscape (deer)

The progressive replacement of plant and animal species due to changing conditions is called: _________________

ecological succession

What unique organisms are able to colonize barren rock? What key role do they play in facilitating other species' colonization of that area?

Lichens are able to colonize barren rock. This allowed soil to form, then moss. As soil builds up over time, grasses, then shrubs, then trees are able to grow.

We measure biodiversity in terms of the number and abundance of species, but also in two other ways. What are they (name them)?

Genetic Diversity and Ecological Diversity

Name the three elements that comprise biodiversity.

Genetic Diversity

Species Diversity

Ecological Diversity

What is ecological diversity? Why is it important to ecosystems?

Ecological diversity is the variety of habitats, niches, trophic levels, and community interactions

Which group of organisms is most abundant on Earth to the best of our knowledge?

Insects

Rearrange this list in order of least to greatest species abundance. (3 pts)

Bacteria, Fungi, Insects, Molluscs, Plants, Vertebrates

Bacteria, Vertebrates, Molluscs, Fungi, Plants, Insects

What is the difference between extinction and extirpation?

Extinction: when a species is extinct everywhere on Earth

Extirpation: when a species is extinct in one region, but still present elsewhere, which means reintroduction to the extinct region is possible

What is endemism?

Plants and animals species that exist only and one location on earth

What is a biodiversity hotspot?

Regions that contain large numbers of endemic species

Which two groups of organisms, though not abundant in number of species, are at the greatest risk of extinction?

plants and vertebrates

Which group of organisms, though abundant in number of species, is at the lowest risk of extinction? (name)

insects

Define deforestation

Deforestation is the net loss of trees in a forested area

Terrestrial biome locations are determined by __________________________________________, but they are characterized by their ______________________________________________________.(

climate

dominant vegetation and other organisms that live there

Which forest biome has the most nutrient-rich soil? Explain why.

Temperate forests have the most nutrient rich soil because they do not have rapid nutrient cycling, less biodiversity, and cooler temperature slow down the speed at which organic matter decays

Which forest biome has the least nutrient-rich soil? Explain why.

Tropical rainforests because there is rapid nutrient cycling, so the nutrients cannot be absorbed into the soil

Are boreal forest soils more similar to temperate forest, or tropical forest soils?

temperate forest

Which forest biome has the thickest soils?

Boreal or Temperate, not sure (?)

Forests cover what proportion of Earth's landmass?

30%

Forests contain what proportion of Earth's terrestrial life?

50%

Forests contain what proportion of Earth's green, photosynthesizing leaves?

60%

What is the underlying reason that Haiti's forests have been so much more

degraded than those in the Dominican Republic?

Lower standard of living(?)

What proportion of Haiti's original forest cover has been lost?

98 %

What proportion of Haiti's original forest cover remains?

<2%

Name two crops grown in Haiti, whose cultivation has led to forest loss.

coffee and sugar

What reason, other than clearing land for agriculture, has led to modern deforestation in Haiti?

using charcoal made from wood to burn for heat and electricity

Areas that store more carbon than they release are called _________________________.

carbon sinks

In what two main ways does deforestation alter air quality?

1) less forests = more CO2 in air

2) less oxygen being produced, diminishing air quality

In what two main ways does deforestation alter atmospheric carbon balance?

increased Carbon and decreased oxygen levels

Why is it misleading to call forests the lungs of the planet?

forests breath CO2 and produce oxygen, the opposite of human lungs

Label the four forest layers indicated in the following figure. (4 pts) and indicate each layer's characteristics in point form.

Emergent layer: a few trees above the general level of the forest canopy

Canopy: the crowns of the dominant trees shade the layers below

Understory: trees and shrubs here are adopted to shade; saplings will grow rapidly when a spot in the canopy opens

Forest Floor: this lowest level contains leaf litter, decomposing plant materials, herbs, flowers, and seedlings

Why is vertical forest stratification important?

Vertical forest stratification is important because each layer of the forest provides distinct food and habitat for animals, fungi, and microbes that help the ecosystem

Name two ecosystem services that forests provide.

watershed services

atmosphere and climate effects

Name two economic values of forests.

Goods and Jobs

Name the three main human activities that continue to cause a net loss of forests.

conversion to agricultural land

harvesting for wood

urbanization

Most deforestation in Canada is in which forest biome?

boreal forest

Most deforestation in Canada is due to________________________.

agricultural expansion

Which logging method is best for maintaining forest biodiversity?

Shelterwood Harvesting