Topic 6: Ecology and Human Impact on the Environment Flashcards
Biosphere
Areas on earth where we can find life
Species
interbreeding population of organisms
Community
all the different populations in the ecosystem
Ecology
The study of the interaction between the living and nonliving things
Ecosystem
The interaction between living (biotic) and nonliving (abiotic) in a given area
Abiotic
Nonliving
Biotic
Living
Abiotic factors influence…
What types of organisms can live in the habitat
Examples of abiotic factors influencing what organisms can live in what habitats:
a) Temperature in Florida vs Alaska
b) amount of sunlight at the top of a lake vs the bottom
Biotic factors help to…
Recycle abiotic materials
Examples of biotic factors recycling abiotic materials
a) Aerobic respiration breaks C6H12O6 down for ATP and releases the carbon dioxide and water
To remain stable (self sustaining) ecosystems must have what 4 things?
1) Constant source of energy
2) Organisms that can convert the energy into usable form and pass it on to others
3) Diversity
4) Recycle of materials
What are energy sources for an ecosystem?
Sun or chemicals
Autotrophs
Plants; use sunlight and CO2 to make sugar (organic)
Heterotrophs
Animals; consume the sugar made by autotrophs for energy in respiration
Diversity
Many different producers and consumers. If one plant species dies than another can pick up the slack.
Recycle of materials
Organisms must break dead things down so the nutrients in them can be used again. Bacteria and fungi decompose dead producers and consumers down to release nitrogen. The nitrogen is then used by other plants to grow.
Food chain
Producer –> primary consumer –> secondary consumer
Example of food chain:
Aquatic plant –> aquatic insect –> Fish –> osprey
BLANK supplies the energy, and BLANK recycles the energy in an ecosystem:
The sun supplies, decomposers recycle
Food web
Many food chains that are interconnected
Energy Pyramid
When a consumer eats another organism, the energy is passed from one organism to the next.
What percent of energy is lost to metabolic activities?
90%
Example of metabolic activities that use energy:
a) You have to find the food (lose energy)
b) you have to ingest the food (lose energy)
c) You have to transport the food to cells (lose energy)
d) You have to convert the food to ATP (lose energy)
Does the amount of energy increase or decrease at each level?
Since energy is lost every time it’s transferred from one consumer to the next, the amount decreases at each level.
What is always the foundation of the food/energy pyramid?
Producers
Photosynthesis
The sun uses energy to put CO2 and H20 (inorganic materials) together to make C6H12O6/sugar/glucose/carbs (organic compounds)
Every organism has a BLANK in the habitat
Niche
Habitat
Environment occupied
Producers/ Autotrophs
Plants; can do photosynthesis to make food
Consumers/Heterotrophs
cannot make their own food; rely on other organisms for food
Herbivores
Eat only plants
Carnivores
Eat only other consumers
Scavengers
Eat dead consumers
Predator
Hunt and eat prey
Prey
Try to escape the predator
Parasite
Steals nutrients from a host
Host
Organism that a parasite steals nutrients from
Carrying Capacity
amount of organisms that can be supported by the habitat
What does carrying capacity depend on?
The amount of food or space available. Ex) the amount of rabbits (prey) available keeps the fox (predator) population stable
Sharing a niche causes…
Competition for food/ resources
Ecological Succession
Ecosystems change/ evolve. Plants and animals change the environment then the new environment attracts new plants and animals
Examples of ecological succession
Lakes can fill in over time, fields turn into mature/ stable forests
What can restart the process of ecological succession?
Fires and clearing the land
Trade off
A decision made by you weighing the good and bad influences our actions have on the environment
Nature Preserves
protect habitat and ecological diversity
Recycle non-renewables
Decrease the amount of landfills (dumps) by using a non-renewable resource over again
Examples of non-renewables that can be recycled
Aluminum cans, glass, metals, fossil fuels
Use renewable resources
sunlight, wood, foods, are constantly being replenished in the environment
Examples of trade offs
Nature preserves; recycling non-renewable resources; using renewable resources; composting; limiting pollution’ regulation/conservation; biological mediation; population growth; hunting/harvesting/farming; non-native species; CO2 emissions; CFC; Pesticides; Chemical pollution
Composting
Decompose naturally, then use as a fertilizer
Limit pollution
Air (smog form cars), water (dumping or runoff from rain)
Regulation/ Conservation
Limit the amount of hunting
Biological Mediation
Use another organism to check the population of another (instead of using pesticides, use a natural predator)
Population growth leads to what types of negative impacts:
deforestation, using fossil fuels, more pollution like acid rain and smog
Hunting/harvesting/farming
Decreases the diversity of a system
Introduction of non-native species
Introduce new/ strange organism to an ecosystem. It will have no natural predators to keep the population stable, so it will exceed its carrying capacity –> this depletes resources for the existing species.
What do CO2 emissions do to the environment?
Cause global warming, changing the biosphere
CFC
Breaks down the ozone layer, letting in more UV
Pesticides
Kill all insects (not just the target). The poison is passed on to other consumers that eat it. It becomes more concentrated in the next animal (biomagnification)
Biomagnification
Poisons from pesticides become more concentrated as they go up the food chain
Chemical Pollution
Air, water or food, may be a carcinogen (causes mutations in DNA). This may affect diversity
Any time diversity is decreased, an ecosystem becomes BLANK stable (more or less)
Less
Limiting Factors
anything that constrains a population’s size and slows or stops it from growing. Some examples of limiting factors are biotic, like food, mates, and competition with other organisms for resources.
Deforestation
the decrease in forest areas across the world that are lost for other uses such as agricultural croplands, urbanization, or mining activities.
Direct Harvesting
to take a species out of it’s environment.
Energy Flow
the flow of energy through living things within an ecosystem
Fossil Fuel
nonrenewable sources of energy formed from the organic matter of plants and microorganisms that lived millions of years ago.
Global Warming
Global warming is the long-term heating of Earth’s surface observed since the pre-industrial period (between 1850 and 1900) due to human activities, primarily fossil fuel burning, which increases heat-trapping greenhouse gas levels in Earth’s atmosphere.
Industrialization
the process of transforming the economy of a nation or region from a focus on agriculture to a reliance on manufacturing.
Nuclear Fuel
the fuel that is used in a nuclear reactor to sustain a nuclear chain reaction; ex) radioactive metals uranium-235 and plutonium-239.
Ozone shield
The high concentration of ozone that is found in the stratosphere around 15–30km above the earth’s surface. It covers the entire planet and protects life on earth by absorbing harmful ultraviolet-B (UV-B) radiation from the sun.
Pollution
when chemicals, particles, or other materials are released into the environment, harming the organisms there.
