Unit 1: Ecology – Sustainable Ecosystems
Chapter 2: Understanding Ecosystems
2.1 Life on Planet Earth
Habitat:
The Spheres of the Earth
1. The _________________

The layer of _____________ surrounding Earth

78% ______________, 21% _____________, 1% ________________________________

Acts like a _______________ by moderating ___________________ - it prevents excessive
heating during the day and cooling during the night

Blocks some incoming _______________________ (like ______________ that damage our skin)

Without the atmosphere, most of Earth’s species _______________________

_______________________________ thick
2. The _________________

Earth’s ___________________________________

Consists of ________________________________ that make up the mountains, ocean floors,
and the rest of Earth’s ____________ landscape

______________ km thick
3. The __________________

All of Earth’s _______________________________________________________

Can be _____, ____________, or __________ Earth’s surface
4. The ___________________

The “zone” around earth where _____________________________________________________

_______________ layer
2.2 Introducing Ecosystems
Ecosystem
Definition:
•
A large ecosystem (ie: a forest) may contain many small ecosystems (ie: a community of bacteria
and fungi living in a rotting log)
Composed of:
a) ____________ Factors
-
________________________________________________________________
-
Ex: ___________________ and __________________________
b) _____________ Factors
- _______________________________________________
- Ex: , ___________, _________, ____________________, and their
___________________ or ___________________________________
Organism – Individuals of _____________ of species (ex: _________________)
Population – all the individuals of a ____________________ in a particular area
(ex: ________________________)
Community – Individuals from ______________________ in the ecosystem
(ex: _____________________________)
The ecosystem is _______________________________________________
Sustainable Ecosystems
Sustainability:
o
_____________________change the biotic and abiotic features of an ecosystem, making
sustainability difficult.
Natural Ecosystems - ____________________________________________________________
Artificial Ecosystems - Ecosystems that are created and maintained by _______________,
like a ___________ or a _________________
o
Not usually ____________________
o
Humans need to maintain their biotic and abiotic features
2.4
Energy Flow in Ecosystems
All organisms require __________ to ______________ and ________________.
All energy comes from the _________.
Types of Energy:
1. ___________ Energy – energy ___________ from the _______
2. ___________ Energy – _________ forms of __________ energy
3. ___________ Energy – energy transferred through _____________ and _____________
-- what __________ the atmosphere, ______________ water, and
____________ winds
4. ___________ Energy – can be ________ in cells and _____________ when needed
-- used by all organisms to perform functions like
____________, __________, and _________________
Distribution of Incoming Solar Radiation
Photosynthesis
-
Process where organisms ________________________________________________________
-
Without it, most life on Earth _________________________________
-
Requires _____________________ (can only be done __________________________)
-
Mostly done by ________________________
-
Green colour comes from_______________, a chemical that captures light energy
Word Equation:
Chemical Equation:
-
The _________ that is formed contains _________________________________
-
Plants __________ this energy in their ______, _______, ________, and _________
-
Done by _________________________________________
o
Organisms that __________________________________________________________
o
Examples: __________________________________________________
Cellular Respiration
-
The “________________” of photosynthesis
-
A chemical reaction where ______________________________________________ to provide
_________ for the cell
-
Can be done during __________________________________
Word Equation:
Chemical Equation:
-
Done by all organisms: both __________________________ and ________________________
-
Consumers:
•
Organisms that obtain energy by ___________________________________
•
_________________ make their own food
•
Without ____________________, consumers could not survive!
•
Examples: _________________________________________
2.5 Food Webs and Ecological Pyramids
Types of Consumers
Herbivore – animal that eats _______________________________________
Carnivore – animal that eats _______________________________________
Top Carnivore - __________________________________________
Omnivore – animal that eats _______________________________________
Scavenger – animal that ___________________________________________________
Insectivore - _______________________________________________________
________________________________________________________
Decomposer - ______________________________________________________
Ecological Niche
- The role of a __________ within its ______________, including ________________,
________________, and __________________
-
No _____________________ occupy identical niches
Food Chain
illustrates _____________________________ in an ecosystem
-
how _________________________________ from one organism to another
-
A sequence of organisms, each feeding on the next. For example,
Trophic Level
– levels that describe the __________________ of an organism along a food chain
Food Web
-

Show a series of
_______________________________________
More complex webs are more _________ than simple ones
because:
What would happen to this food web if all the weasels died
from some disease?
Energy Pyramids
-
Show relationships between _____________________ in ecosystems
-
As you go ________ trophic levels, the amount of energy available ________________
o
This is because organisms can’t ______________________________________. Some is
released as ___________________________.
-
Species in high trophic levels often have __________ energy available to them than species near
the bottom
o
Therefore, their populations are _______________
o
Only _______ of energy from the lower trophic level is passed on to the next level
2.6: Cycling of Matter in Ecosystems
•
Matter cannot be __________________________________________ – substances (like water,
carbon, and nitrogen) are continuously consumed, rearranged, stored, and used on earth.
The Water Cycle
1. Liquid water ___________________, forming water ___________ that moves through the
atmosphere.
2. The vapour eventually ________________, forming ___________________________, and
3. falls to Earth as _____________________.
4. __________________________may enter the soil, groundwater, or bodies of water
5.
Water taken in by plant roots may be released from leaves by __________________________
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
transpiration
The Carbon Cycle
•
Carbon is cycled through the 4 spheres, mostly through __________________________________
__________________________________________
•
Most of Earth’s carbon is ___________________ – it is ____________ in deposits, like fossil fuels,
coal, oil, natural gas, and limestone.
•
A large amount of carbon is also stored in ____________________ and as
_____________________________ in the oceans
1. Photosynthesis uses ________________________________
2. Plants and animals release CO2 into atmosphere through ________________________________
3. Dead plants and animals are broken down by ___________________ - carbon enters the ground.
4. _________________________ occurs over time, into deposits
5. _________________________ occurs as deposits get burned. CO2 enters the atmosphere.
6. and 7. Carbon is stored as _____________________ formed from ________________________
_______________________ (shells of crustaceans)
8. Limestone releases carbon dioxide into the atmosphere when it reacts with ___________________
_______________________________ are affecting the carbon cycle.
•
By __________________________________, we are releasing large amounts of CO2 into
the atmosphere.
•
This raises global temperatures, which melts ice caps, which causes sea levels to
rise, which disrupts ecosystems.
•
_________________________________ is increasing the amount of CO2 in the
atmosphere (because there are ______________________________!)
The Nitrogen Cycle
•
The atmosphere is about 78% nitrogen, but it is difficult to extract from the air_________________
for use by plants and other organisms
1. ______________________________________ occurs when nitrogen is converted to other
compounds like nitrates, nitrites, and ammonia. This happens in 2 ways:
a. By ___________________________________________ in the soil
b. By ___________________
2. ______________________________________ are now available to producers in the soil
3. ________________________ the nitrogen which gets _______________________ the food chain
4. Excess nitrogen is ____________________ as waste and goes back into the soil
5. _________________________ of dead organisms sends nitrogen back into the soil
6. __________________________ can also occur – the opposite of nitrogen fixation. Denitrifying
bacteria will break down nitrates and release nitrogen back into the atmosphere
2.7 Biotic and Abiotic Influences on Ecosystems
Limiting Factor
•
Any factor that _______________________________________________________
•
May be biotic or abiotic
•
__________________________________ are usually limiting factors
Carrying Capacity
•
the ________________________________________ of a species that an ecosystem can sustain
•
a population can only get so large until it _____________________________________
Abiotic Limiting Factors
•
Determine ____________________________________________________
•
Limiting Factors in _________________________ Ecosystems
•
Limiting Factors In ______________________ Ecosystems
•
What human actions are altering these abiotic factors?
Biotic Limiting Factors
•
Determine a ___________________________________
•
Involve different interactions between individuals:
•
Competition –
•
Predation –
•
Symbiosis –
•
Mutualism –
•
Parasitism –
•
Commensalism –
2.8 Major Terrestrial Biomes
Biome
•
Canada’s Biomes
•
Canada has __________ major biomes
o
Growing
Season
Temperature
Soil
Precipitation
Types of
Producers
Types of
Wildlife
British Columbia contains many smaller biomes, including the _______________________
2.9: Major Aquatic Ecosystems
Aquatic ecosystems are classified as either ____________________________ (salt concentration less
than 1%) or _______________________________ (salt concentration of about 3%)
1.
Freshwater
Freshwater ecosystems contain _________________ and _______________ which feed fresh
rainwater to meltwater into ponds or lakes. The nutrient levels of these water bodies greatly
influences the ____________ and _______________ of organisms found in them.
In oligotrophic lakes, the water is _____________ because of the __________ nutrient levels.
In eutrophic lakes, the water is ________________ because of the ___________ nutrient levels
and the growth of ____________________________________________________.
The area of land through which water drains into a single river or lake is called a
_________________.
2. Marine
Much of the ocean supports __________________________ life. The __________________ and
___________________ do not support life, but
_________________________________________ are nutrient rich and do support life.
3 types of areas that are nutrient rich and support life are: _____________________________
____________________________________________________________________________
The ___________________ zone, the area between low tide and high tide, experiences a wide
_______________ of environmental condition. Organisms living there must be able to survive
these ____________________ condition as well as the constant ______________________ of
the waves. To withstand this, most species have
___________________________________________ and _____________________________
3.3
The Importance of Biodiversity
Biodiversity –
Species Richness –

Many species are dying out and becoming _______________

Their habitats are being destroyed at a _________________________ due to
______________________________ like:




Species at Risk in Canada
Classification
Definition
Examples in Canada
3.5: The Introduction of Non-Native Species
Non-Native Species
•
Are introduced either:
a) ____________________ – ie: attached to a boat
b) ____________________ – ie: to control another population
•
Their introduction _____________________ because few species can tolerate a new environment.
•
Sometimes, they are __________________ and can ____________________________________
Invasive Species
•
A non-native species whose ______________________ or __________________________
introduction _________________________________________ the natural environment
•
______________________________native species for resources
•
There are over _________ in Canada
Impacts of Invasive Species
1.
•
Invasive species _____________________ or _______________ native species, resulting in
population decline or extinction.
•
Change ecosystem dynamics by _______________________________ or __________________
•
They can _______________________________________, leading to financial loses.
•
Species loss has negative effects on __________________________________
•
Reduced water quality has impacts on _______________________________________________
•
_______________________________ organisms are introduced, like West Nile virus.
•
_________________________ need to be used to control invasive species population, affecting
2.
3.
4.
health and causing pollution.
Controlling Introduced Species
1.
•
_______________________ are used on forest and agricultural pests.
•
May also ___________________________________________ and pollute the air, water, and soil.
•
We can put up ________________________ or _________________________ invasive species
2.
by hunting, trapping, and cutting down or burning plants.
3.
•
_____________________________________ that control the invasive species.
4.2: Managing the Soil
Soil
Soil is one of earth’s _________________________________________ and is critical to our survival
•
___________ depend on soil for ___________________________________________
•
___________ depend on soil for ___________________________________________
Soil is more than just dirt!
•
It is a ________________ of minerals, water, dissolved nutrients, air, and decomposing matter
•
It is _________________ to organisms, from microscopic bacteria to large burrowing mammals
Managing Soil Nutrients
•
The most important nutrients for plants are ____________________________________________
•
How do we replace these nutrients? Use ___________________________
•
There are two types of fertilizers:
Natural Fertilizers
Definition
Examples
Pros
Cons
Synthetic Fertilizers
Environmental Impacts of Synthetic Fertilizers
1. Nutrients are __________________________________ in synthetic fertilizers
•
Nutrients enter the soil rapidly and _______________ the soil organisms.
•
Soil then has less _____________________________________________
•
Soil becomes _________________________ on synthetic fertilizers.
•
Soil is more likely to ____________________.
2. Leaching
•
Occurs when _______________________________ from the soil as_________ passes through it.
•
_____________________________ (which we drink) becomes _________________________
with nitrogen, causing health problems.
•
Increases the ________________________________ in aquatic ecosystems, which decreases
the level of _____________________ in the water, killing fish and other organisms.
4.4 & 4.5: Pests, Poisons and Pesticides
Pests
•
Organisms that might ___________________________ or _________________ crop species
•
i.e: _____________________________________________
Pesticide
•
A substance used to ______________________________.
•
May be toxic to a ____________________ of species, or to a __________________________ of
species.
•
Cause ____________________ or _______________________ harm to the pest
•
Can help farmers __________________________________ or ___________________________
of biting insects that spread diseases, like mosquitoes.
•
Can also have many negative effects
Issues with Pesticides
1. Applied by aerosol (__________________________)
•
Some pesticide _____________________________________ because it’s carried away by the
________, causing _________________________.
2. Kill species they were not intending to kill
3. Pesticide Resistance
•
Over time, pests can become ____________________ to pesticides. Farmers have to apply
_________________________ of this pesticide, or _________________ to a different pesticide.
Pesticides gone wrong: DDT
1. DDT is a pesticide that was used in Borneo in the 1950s to
______________________________________________________________.
2. It also _________________________, so they were not able to prey on the thatch-eating
________________________. These caterpillars caused _________________ to villager’s homes.
3. DDT also ___________________________________ that were then consumed by ____________.
The DDT damaged the nervous system of the lizards. _______ ate the lizards and were also
poisoned.
4. When the cats disappeared, the __________ population in the village increased dramatically.
5. The ____________ on the rats carried the _____________ – having more rats meant that the
plague spread faster.
6. To prevent an epidemic, a large number of _______________________ had to be introduced to
control the rats.
Bioaccumulation
•
Happens when an organism _________________________________________
•
Pesticide _________________ in their body and cannot be easily ____________________
Bioamplification
•
As larger organisms consume the infected organisms, the toxins are _____________________
and ____________________ the food chain. The higher up on the food chain, the
_______________________________________ the pesticide becomes.
•
This is what happened with DDT, which greatly affected
many species of ____________________