115 terms

APES CHAPTER 3- ecosystem ecology


Terms in this set (...)

a biological community of interacting organisms and their physical environment.
an organism that is able to form nutritional organic substances from simple inorganic substances such as carbon dioxide
photosynthesis ***
producers use solar energy to convert CO2 and H2O into C6H12O6 (a form of potential
Cellular respiration ***
a process that unlocks the chemical energy stored in the cells of organisms
incapable of photosynthesis and must obtain their energy by consuming other organisms
Primary Consumer
heterotrophs that consume producers ( herbivores)
Secondary Consumer
carnivores that eat primary consumers
tertiary consumer
carnivores that eat other carnivores (secondary consumers)
trophic level
levels of organisms that consume one another
carnivores that consume dead animals
organisms that specialize in breaking down dead tissues and waste products
the fungi and bacteria that complete the breakdown process by recycling the nutrients from dead tissues and wastes back into the ecosystem
Gross Primary Productivity **
measure of how much photosynthesis is occurring over some amount of time
Net Primary Productivity **
the energy captured minus the energy respired by producers
the total mass of organisms in a given area or volume
standing crop
the amount of biomass present in an ecosystem at a particular time
Ecological Efficiency ***
the proportion of consumed energy that can be passed from one trophic level to another
the region of our planet that supports life
biochemical cycles
the movements of matter within and between ecosystems involve biological,geological, and chem. proccesses
Hydrologic Cycle ***
the movement of water through the biosphere
the conversion of a vapor or gas to a liquid
rain, snow, sleet, or hail that falls to the ground.
cause a substance to be deposited in solid form from a solution
the process of water movement through a plant and its evaporation from aerial parts, such as leaves, stems, and flowers
the combined amount of evaporation and transpiration, used by scientists as a measure of the water moving through an ecosystem
run off
the draining of water (or substance carried in it ie. fertilizer) from the surface of an area of land, to an ocean
Carbon Cycle ****
the series of processes by which carbon compounds are interconverted in the enviro. mainly involving the incorporation of CO2 into living tissue by photosynthesis and its return to the atmosphere through respiration, the decay of dead organisms, and the burning fossil fuels.
6 key elements that organisms need in relatively large amounts : nitrogen, phosphorous, potassium, calcium, magnesium, and sulfure
limiting nutrient / limiting factor
lack of nitrogen constrains the growth of the organism
Nitrogen Cycle ***
the series of processes by which nitrogen and its compounds are interconverted in the enviro. and in living organisms, including nitrogen fixation and decomposition
Nitrogen Fixation ***
the chem process by which atmospheric nitrogen is assimilated into organic compounds , especially by certain microorganisms as the first part in the nitrogen cycle.
Ammonification ***
the process in which microorganisms (ie bacteria) break down organic matter and animal waste into ammonia, which can be used by plants as a natural fertilizer
Assimilation ****
producers take up either NH4+ or NO3- consumers take in nitrogen by eating producers
denitrification ***
denitrifying bacteria in a O-poor soil and stagnant
H2O -> NO3 -> N2O ->N2
Nitrification ***
nitrifying bacteria convert NH4+ into NO2- and then into NO3-
(process) negatively charged nitrate ions do not bind easily to soil particles, most of which are negatively charged. As a result nitrate is readily transported through the soil with water
a temporary change in enviro. conditions that causes a distinct change in an ecosystem
Watershed **
all of the land in a given landscape that drains into a particular stream, river, or wetland
Resistance ***
a measure of how much a disturbance can affect the flows of energy and matter
Resilience ***
the rate at which an ecosystem returns to its original state after a disturbance
restoration ecology
growing interest in restoring damaged ecosystems has led to this scientific discipline
Instrumental Value ***
it has worth independent of any benefit it may provide to humans
goods that humans can use directly
Biomass Pyramid ***
shows bio productivity at each trophic level in a given ecosystem
Energy Pyramid ***
model of energy flow in a community
Numbers Pyramid ***
depicts the relationship in terms of teh number of producers, herbivores and carnivores at their successive trophic levels
the fusion of organic compounds by bacteria or other living organisms using energy obtained from reactions involving inorganic chemicals, typically in the absence of sunlight
reversing the deforestation of haiti
planting mango trees so they can keep profits up and prevent more deforestation
what are 2 examples of an ecosystem
1) aquatic 2) terrestrial
Why did scientists have to include land outside of Yellowstone National Park in the plan for managing the Yellowstone ecosystem?
Because some animals like grizzly bears spend time inside and outside the 1-million-hectare park, animals in the wild can't be contained in an invisible fence
what is the balanced chemical equation for photosynthesis
6CO2 + 6H2O ------> C6H12O6 + 6O2
what is the balanced chemical equation for Cellular Respiration
C6H12O6 + 6 O2 -----> 6 CO2 + 6 H2O
what's the difference between heterotroph and autotroph
Hetero: incapable of photosynthesis and must obtain their energy by consuming other organisms

Auto: an organism that is able to form nutritional organic substances from simple inorganic substances such as carbon dioxide.
Grass is a primary producer because it
makes their own food from sunlight and/or chemical energy from deep sea vents
A zebra is a primary consumer because it eats
primary producers
A lion is a secondary consumer because it eats
primary consumers
A hyena is a scavenger because it eats
leftovers of other predators. But they also hunt
A dung beetle is a detritivore because it eats
carcases of primary consumers
Bacteria, fungi and earthworms are decomposers because they
decompose material
difference between NPP and GPP
NPP: the energy captured minus the energy respired by producers

GPP: a measure of how much photosynthesis is occurring over some amount of time
equation that links NPP and GPP
NPP = GPP - plant respiration
Which two continental ecosystems (also called terrestrial ecosystems) are the most productive
swamps/marshes and tropical rain forests
Which three continental ecosystems are the least productive?
Tundra, desert scrub, extreme desert
Which two marine ecosystems (ocean related ecosystems) are the most productive?
Coral reefs and salt marshes
Which marine ecosystem is the least productive?
Open ocean
What is the relationship between biomass and NPP?
they're closely related. net primary production is basically the accumulation of biomass.

so when net primary productivity increases, biomass increases.
Explain why a slow growing forest can have a very low NPP and yet store a massive amount of biomass.
slow-growing forests have low productivity; the trees add only a small amount of biomass through growth and reproduction each year. However, the standing crop of long-lived trees- the biomass of trees that had accumulated over hundreds of years is quite high
Explain why algae in the ocean can have a very high NPP and a very low amount of stored biomass.
the high growth rates of algae living in the ocean make them extremely productive but bc primary consumers eat these algae so rapidly, the standing crop of algae at any particular time is relatively low
Explain why a vegetarian diet is much more ecologically efficient than an omnivorous diet.
by eating less intensively farmed meat, we can make use of the energy from the sun more efficiently, preventing energy expenditure in not only raising meat, but packaging, processing and transporting it, sometimes over huge distances.
In cycles there are reservoirs (also called pools) and flows (also called processes). Matter is what
matter is stored in reservoirs;
flows are when matter is moved from one reservoir to another.
The Hydrologic Cycle: ****
The water cycle is driven by GRAVITY and SOLAR ENERGY. All steps in the water cycle that flow downward are driven by gravity. All steps in the water cycle that flow upwards are driven by solar energy.
3 examples of reservoirs in the water cycle
(places where water is stored)
Oceans, Icecaps, and Lakes
What are the steps to the water cycle
1. evaporation
2. condensation
3. precipitation
4. transpiration
5. runoff
(first step in water cycle)
the sun heats water in rivers, lakes, and the ocean and turns it into vapor or steam, which then rises into the air.
(second step in water cycle) the water vapor cools and turns into tiny water droplets that attach to each other and form clouds
(third step in water cycle) water falls from the clouds as rain, snow, sleet or hail
(fourth step in water cycle) moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapor and is released to the atmosphere
(fifth step in water cycle) some water stays on the earth's surface and flows into rivers, lakes, and reserviors
3 things that can happen to water that falls on land
1) Infiltration - seep into ground
2) runoff- water flows to water sources
3) evaportransporation - go back to atmosphere
4 ways humans can alter the water cycle
1) Over consumption disrupts the water cycle pattern
2) Polluting affects the flow of the waters
3) Deforestation, if no more trees they cannot absorb rainwater and all the water would flow into straight into a river or other water source making it overflow
4) Turning land over for commercial use, disrupts the flow of water
The Carbon Cycle *****
As Carbon is the basis of life, this cycle is extremely important. For environmental scientists, it is also very important because the carbon cycle helps us understand global climate change by helping us understand where excess CO2 in the atmosphere might end up and how we might be able to increase storage in reservoirs besides the atmosphere
List three examples of carbon reservoirs
(where carbon is stored)
1) Oceans 2)atmos. 3) land biospheres
Steps in Carbon Cycle
1) photosynthesis
2) respiration
3) exchange
4) sedimentation
5) extraction
6) combustion
Photosynthesis in Carbon cycle
1. atmospheric CO2 is converted into sugars
Respiration in Carbon Cycle
2. living organisms produce energy bc of their intake of Oxygen and release CO2
Exchange in Carbon Cycle
3. the amount of CO2 released from the ocean into the atmosphere roughly equals the amount of atmospheric CO2 that diffuses into ocean water
Sedimentation in Carbon Cycle
4. the tendency for particles in suspension to settle out of the fliuid in which they are led and come to a rest against a barrier. This is due to their motion through the fluid in response to the forces acting on them
Extraction in Carbon Cycle
5. (does not alter this cycle) extracts fossil fuels by humans
Combustion in Carbon Cycle
6. (last)whether of fossil fuels or of timber in a Forrest fire releases carbon into atmosphere as CO2 or into the soil as ash
Name two ways humans alter the carbon cycle
1) deforestation makes it harder to filter CO2
2) burning fossil fuels
The Nitrogen Cycle ****
The nitrogen cycle allows atmospheric nitrogen to be converted into a form plants can use.

this is the trickiest cycle to learn, but frequently appears on the AP EXAM, so be sure you know it! It is a critical cycle because most of the nitrogen on earth is stored in the atmosphere, but plants can only absorb nitrogen through the soil.
Explain what is meant by a limiting nutrient. Why is nitrogen often a limiting nutrient?
The limiting nutrient is related to the plant's growth. Nitrogen is a key element in amino acids. Without nitrogen, a plant cannot make amino acids. Without amino acids, a plant cannot synthesize proteins. Without proteins, the plant cannot make new cells required for growth and repair.
Where is most of the nitrogen on earth found? In what form?
In the atmosphere as a gas N2 -> NH3
What two important macromolecules contain nitrogen
steps of the Nitrogen Cycle
1) Nitrogen Fixation
2) Nitrification
3) Ammonification
4) Denitrification
Phosphorus Cycle ***
* Plants need phosphorus in the form
of phosphate (PO43-)
* Phosphorus does not cycle through
the atmosphere
* Phosphorus is typically a limiting
factor for plants (along with nitrogen)
* Excess phosphorus in aquatic
ecosystems leads to eutrophication
Sulfur Cycle ***
* Hydrogen sulfide (H2S) is poisonous
gas that smells like rotten eggs and
comes from anaerobic decomposition.
* Sulfur dioxide (SO2) is a colorless
gas that comes from burning coal
and volcanoes
* Sulfuric Acid (H2SO4)is the main
component of acid rain - forms
when sulfur dioxide and water
vapor mix in the atmosphere;
often as a result of burning coal
List 5 natural disturbances
4 anthropogenic disturbances.
* Natural: hurricanes, ice storms,
tsunamis, tornadoes, volcanic
eruptions, forest fires
* Anthropogenic: human settlements,
agriculture, air pollution, deforestation
When studying Hubbard Brook, what did scientists discover (or confirm) about the impacts of deforestation?
When trees are no longer present to take up nitrate from the soil, nitrate leaches out of the soil and ends up in the stream that drains the watershed
What is the difference between resistance and resilience?
Resistance is the ability not to be affected by something, while resilience is the ability to bounce back from something happening to it.
Provide 5 examples of provisions.
Lumber, food crops, medicinal plants, natural rubber, and furs
Provide 1 example of a regulating service.
Natural ecosystems
Provide 2 examples of support systems
family , natural ecosystems
Provide 1 example of resilience
Rubber band (gets stretched with tension but bounces back to almost normal)
Provide 2 examples of cultural services
Scientific funding (grants), government support
which of the following is NOT an example of an abiotic component of an ecosystem

water, minerals, sunlight, fungi, air
which of the following is NOT a characteristic of ecosystems

biotic comp, abiotic comp, recycling of matter, distinct boundaries, wide range of sizes
distinct boundaries
which biochemical (s) cycle does NOT have a gas component

potassium, sulfur, phosphorous
potassium and phosphorus
which macronutrient is required by humans in the largest amounts
roughly what percentage of incoming solar energy is converted into chemical energy by producers
the npp of an ecosystem is 1 kg C/m^2/ year, and the enrgy needed by the producers for their own respiration is 1.5 kg C/m^2/ year. the gpp of such an ecosystem would be
2.5 kg C/m^2/ year
an ecosystem has an ecological efficacy of 10% if the producer level contains 10,000 kilocalories of energy how much energy does the tertiary consumer level contain
10 kcal
small inputs of this substance commonly a limiting factor in aquatic ecosystem, can result in algal bloom and dead zones

(dissolved CO2, Sulfur, Dissolved Oxygen, Phosphorous, Potassium)
research at Hubbard brook showed that stream nitrate concentrations in two watersheds were ____ before clear-cutting and that after 1 watershed was clear-cut its stream nitrate concentration was _____
similar , increased
the anticancer drug taxol was originally extracted from the bark of pacific yew tree. this drug is an example of a type of ecosystem service known as

(cultural service, support system, provisions, resilience, regulating srevices)
after a severe drought, the productivity in an ecosystem took many years to return to pre-drought conditions. this observation indicated that the ecosystem has

(high resilience, low resilience, high resistance, low resistance, equal resilience and resistance. )
low resilience