Environmental Science for AP* Chapters 3 Questions
My teacher made questions for this chapter. Here I have converted them into flashcard format.
Terms in this set (81)
Why is it difficult to determine what the boundaries to an ecosystem are? Contrast the examples of a cave versus a forest or desert
It is difficulty to determine the boundaries to an ecosystem because ecosystems like forests and deserts are connected to other ecosystems. A cave, in comparison is easier to determine the boundaries of, because it is mostly isolated.
How does most energy enter ecosystems? What types of energy conversion occur within ecosystems?
Most energy enters ecosystems as solar energy that plants convert into chemical energy, which is passed through the food chain.
How are trophic levels related to flow of energy through an ecosystem? What form is this energy in? ___
Energy flows through an ecosystem in trophic levels, where 10 percent of energy is passed to each higher trophic level. This energy is in chemical form.
What does the productivity of an ecosystem measure? __
The productivity of an ecosystem measures the energy in an ecosystem.
What is the difference between Gross Primary Productivity and Net Primary Productivity? Which one do you think has more of an influence on an ecosystem? _____
Gross Primary Productivity is the total energy made to be used by plants, the Net Primary Productivity is this energy minus energy lost in respiration. Net Primary Productivity has more of an influence, because it is the amount of actual consumable energy.
Approximately what percentage of incoming solar energy do plants capture during photosynthesis? What happens to the rest of it? _____
Energy capture 1% of incoming energy and the rest is reflected or passed through producers without being absorbed
Why is only a small fraction of energy at each trophic level transferred up to the next trophic level? Where does the rest of the energy go? ____
Only a small fraction of energy is transferred up to the next trophic level because of ecosystem's entropy. The rest is lost as heat.
Hydrologic Cycle: Evaporation (what step is it, what makes this happen, why is it important?)
1. Solar heating of oceans, lakes, and soils and water enters the atmosphere to be redistributed
Hydrologic Cycle: Condensation (what step is it, what makes this happen, why is it important?)
2. cooling of water vapor in the atmosphere, form clouds that aid in precipitation
Hydrologic Cycle: Precipitation (what step is it, what makes this happen, why is it important?)
3. heaviness of condensed clouds, returns water to the Earth
Hydrologic Cycle: Absorption or runoff (what step is it, what makes this happen, why is it important?)
4. Water meeting the Earth's surface, which cannot absorb it fast enough, this carries whatever is into the soil into rivers, ponds and lakes with more water. The rest of the water is hydrates ecosystem by being absorbed into the soil.
Explain the hydrologic cycle.
Water is evaporated from the ground or from leaves of plants (transpiration), condenses in the atmosphere as it cools, drops as the clouds condensing get too heavy, and finally nourishes the ecosystem by being taken up by plants, percolating into soil, entering groundwater or running off the surface of the land
Carbon Cycle: Photosynthesis (what step is it, what organism/process does it, why is it important?)
1. Plants absorb CO2 in photosynthesis, and converts abiotic CO2 into biomass at the base of the food chain
Carbon Cycle: Respiration (what step is it, what organism/process does it, why is it important?)
2. All organisms, releases Carbon back into the atmosphere to be used in photosynthesis or simply add to atmospheric CO2
Carbon Cycle: Exchange (what step is it, what organism/process does it, why is it important?)
3. CO2 in the atmosphere and CO2 dissolved in water, allows dissolved CO2 to undergo sedimentation and evaporated CO2 to be absorbed in CO2
Carbon Cycle: Sedimentation and burial (what step is it, what organism/process does it, why is it important?)
4. Dissolved CO2 turning into limestone, biomass pools turning into fossil fuels, deposits store carbon away for long periods of time
Carbon Cycle: Extraction (what step is it, what organism/process does it, why is it important?)
5. Humans, extraction of carbon allows it to be burned in combustion
Carbon Cycle: Combustion (what step is it, what organism/process does it, why is it important?)
6. Humans or natural events, humans or forest fires can release carbon back into the atmosphere to be exchanged
Explain the carbon cycle.
Producers photosynthesize and turn CO2 into biomass, and then carbon is returned to the atmosphere through respiration. The Carbon in the atmosphere and that in dissolved water is constantly exchanged and this leads to sedimentation of dissolved CO2. Burial of organism also stores carbon away as fossil fuel. Eventually humans remove the carbon through extraction and through combustion of trees or fossil fuels, release it back into the atmosphere.
Nitrogen Cycle: Nitrogen Fixation (what step is it, what organism/process does it, why is it important?)
1. N-fixing bacteria (legume roots) or fires/lightning or fertilizer, puts N back into the base of the food chain, fertilizer manufacture
Nitrogen Cycle: Assimilation ((what step is it, what organism/process does it, why is it important?)
2. Producers, consumers, allows organisms to use nitrogen as a macromolecule
Nitrogen Cycle: Ammonification (what step is it, what organism/process does it, why is it important?)
3. Decomposers, allows decomposers to break nitrogen into Ammonium, an ion that can later become N2 in the atmosphere
Nitrogen Cycle: Nitrification (what step is it, what organism/process does it, why is it important?)
4. Nitrifying bacteria, nitrate can be converted into nitrous oxide and then nitrogen gas to be released into the atmosphere.
Nitrogen Cycle: Denitrification (what step is it, what organism/process does it, why is it important?)
5. Denitrifying bacteria, helps make oxygen poor soil richer in oxygen by converting nitrate into nitrous oxide and eventually atmospheric nitrogen gas.
Explain the nitrogen cycle.
Nitrogen fixation converts N2 from the atmosphere (more quickly than abiotic processes. Producers absorb nitrogen into the food cycle in assimilation. Then the ammonification process takes the organisms that have absorbed nitrogen through the food cycle and puts the nitrogen back into the ground as ammonium. Nitrification then turns ammonium first into nitrite and then nitrate. Finally denitrification processes the nitrate back into the atmosphere as nitrogen gas.
Phosphorus Cycle: Weathering of rocks (what step is it, what organism/process does it, why is it important?)
1. Weathering, releases P from rocks into reactive forms usable by organisms
Phosphorus Cycle: Run off (what step is it, what organism/process does it, why is it important?)
2. Aquatic systems or plants, the run off of phosphate fertilizer can greatly increase producer growth and often cause algal blooms to clog systems
Phosphorus Cycle: Excretion (what step is it, what organism/process does it, why is it important?)
3. Animals, this can also release excess phosphorus into water systems
Phosphorus Cycle: Precipitation and Conversion (what step is it, what organism/process does it, why is it important?)
4. Aquatic systems, dissolved phosphates become ocean sediments and later mountains of phosphate rocks
Phosphorus Cycle: Geologic Forces (what step is it, what organism/process does it, why is it important?)
5. Montainous systems, Mountains are formed by phosphorous rocks pushed up by geological forces
Explain the phosphorus cycle.
In the phosphorous cycle phosphate is released from rocks and into runoff along with phosphorus from animal execration. THe dissolved phosphates in the water run out into the ocean and become ocean sediments and mountains of phosphate rock.
How does the water cycle help facilitate other cycles?
Water allows essential molecules (including carbon, nitrogen and phosphorus) to travel along their biogeochemical cycles.
What human activities cause an impact on the hydrologic cycle? What are these impacts?
Harvesting trees can have an impact on evapotranspiration by reducing biomass and paving over land surfaces can reduce percolation. Both of these activities can increase runoff causing erosion or flooding. Diverting water from one place to another can also reduce land in certain areas causing droughts with devastating effects.
Explain the different between the "fast" and "slow" parts of the carbon cycle.
Fast: processes associated with living organisms (respiration, extraction and combustion) Slow: exchange, sedimentation and burial
Which natural (nonanthropogenic) processes normally return buried carbon to the atmosphere to balance out carbon that is buried through sedimentation
Volcanic eruptions can return buried carbon to the atmosphere to balance out carbon buried through sedimentation.
Which 2 macronutrients most frequently serve as the limiting nutrient for plant grown in an ecosystem? Is it different for terrestrial vs. aquatic ecosystems?
Phosphorus and nitrogen are the biggest limiting nutrients. In terrestrial ecosystems legumes fix nitrogen and in aquatic systems cyanobacteria fix nitrogen. In aquatic systems phosphorus often comes from fish or runoff from terrestrial ecosystems. Often runoff from terrestrial ecosystems destroys aquatic ecosystems.
What are results of a sudden influence of excess nitrogen and phosphorus into an ecosystem?
Adding nitrogen to soils and fertilizers increases atmospheric concentration, which can alter distribution or abundance of species. Leached phosphorus can lead to algal blooms which clog the aquatic ecosystem.
How do heterotrophs (consumers) obtain their supplies of macronutrients?
Heterotrophs obtain macronutrients by eating plants that have absorbed them.
When investigating environmental systems, why do scientists often select watersheds as an area in which to study ecosystems and nutrient/energy cycling?
They usually house watersheds because water doesn't leave through percolation (because of a watershed's bedrock) so must leave through evapotranspiration or runoff
What characteristics do you think give ecosystems high resistance and high resiliency against change?
I think that biodiversity and access to sun and abundant resource of water give an ecosystem high resiliency against change.
List the types of ecosystem services: ______
provisions, cultural services, regulating systems, support systems, resilience
How can the value of ecosystem services be measured?
Intrinsic vs instrumental value.
A particular location on Earth distinguished by its particular mix of interacting biotic and abiotic components.
Organisms that use the sun's energy to produce usable forms of energy.
The process through which producers use solar energy to convert to CO2 and water
A process that unlocks the chemical energy stored in the cells of organisms
Organisms that eat producers or other consumers to get food
Consume primary producers (carnivores)
Consume secondary consumers (carnivores)
Trophic Levels ___
Successive levels of organisms consuming one another
The sequence of consumption from producers through tertiary consumers.
A more realistic model for ecosystems that takes into account the complexity of nature.
Carnivores, like vultures, that eat dead animals.
Organisms like dung beetles that specialize in breaking down dead tissues and waste products (detritus.)
Organisms that complete the breakdown process by recycling nutrients from dead tissues and waste back into the ecosystem.
Gross Primary Productivity (GPP)
The total amount of solar energy captured via photosynthesis in an ecosystem at a given time.
Net Primary Productivity (NPP)
Energy captured - energy respired.
Total mass of all living matter in a specific area.
Standing Crop _____
The amount of biomass present in an ecosystem at a given time.
The proportion of consumed energy that can be passed from one trophic level to another.
Trophic Pyramid ___
A representation of the distribution of biomass among trophic levels.
A region of our planet where life resides.
The movement of matter within and between ecosystems involving biological, geological and chemical processes.
The movement of water through biosphere.
The release of water from plant leaves by photosynthesis.
The combined amount of evaporation and transpiration.
Water that travels on land's surface after heavy rain.
Six key elements organisms need in relatively large amounts.
A nutrient which, if lacking in an organism, can constrain the organism's growth.
The process through which organisms convert N2 bass into NH3+, ammonia
The process through which a nutrient (like nitrate) is readily transported through the soil with water.
An event caused by physical, chemical or biological agents that results in changes in population size or community composition.
All the land of a given landscape that drains into a particular stream, river, lake or wetland.
A measure of how much a disturbance can affect the flow of energy and matter in an ecosystem.
The rate at which an ecosystem returns to its original state after a disturbance.
A new scientific discipline aimed at restoring damaged ecosystems.
Intermediate Disturbance Hypothesis
Ecosystems experiencing intermediate levels of disturbance are more diverse than those with high or low disturbance levels.
A species' worth as an instrument or tool that can be used to accomplish a goal.
A species' worth independent of any benefit it may provide to humans.
Goods that humans use directly.