Ecosystems APES Test

What are typical units for GPP?

Units of kilograms of carbon taken up per square meter per day (kg C/m2/ day).

Levels of a Pyramid (Trophic Levels)

tertiary consumers secondary consumers primary consumers producers

intermediate disturbance hypothesis

the hypothesis that ecosystems experiencing intermediate levels of disturbance are more diverse than those with high or low disturbance levels

carbon cycle

the movement of carbon from the nonliving environment into living things and back

ammonification

decomposers convert organic waste into ammonia

List three uses for phosphorus in the body.

DNA, RNA, and ATP.

atmosphere

A thin layer of gases surrounding Earth

What is biomass?

Biomass is the total mass of all living matter in a specific area.

A plant typically takes in ...% of the sun's energy. The NPP of any system ranges from about ... to ..... So about .....% of the sun is really being represented by NPP.

1,25, 50, 0.25

Ecological efficiency ranges from ... to ...% but the average is ...%.

5,20,10

pyramid of energy flow

90% of energy lost with each transfer Less chemical energy for higher trophic levels

What is a benefit of percolation of water through soil?

A benefit is that it can help benefit groundwater and aquifer recharges.

Macronutrients

A chemical substance that an organism must obtain in relatively large amounts

Distinguish between a food chain and a food web.

A food chain is the sequence of consumption from producers through tertiary consumers, while a food web is a model that shows the transfer of energy between organisms

What is a limiting nutrient and what does that have to do with nitrogen?

A limiting nutrient is one that is required for the growth of an organism but is a lower quantity than other nutrients. Nitrogen is an example of a limiting nutrient.

What is a species?

A species is a group of similar organisms that are able to reproduce together and share genetic material.

What is a trophic level?

A trophic level is the successive levels of organisms consuming one another

What is a watershed?

A watershed is all of the land in a given landscape that drains into a particular stream, river, lake, or wetland.

Distinguish between abiotic and biotic components in an ecosystem. Give at least five examples of each

Abiotic components are the nonliving things in an ecosystem while biotic components are the living factors of an ecosystem. Biotic: Animals, microorganisms, insects, plants, and decomposers. Abiotic: Temperature, salinity, flowing water, light, and humidity.

biological community

All of the populations of organisms living and interacting in a particular area

Niche

An organism's particular role in an ecosystem, or how it makes its living.

What is anaerobic respiration? List at least one type of organism from the book that performs anaerobic respiration.

Anaerobic respiration is a process by which cells convert glucose into energy without the use of oxygen. Organisms that use this type of respiration are bacteria.

restoration ecology

Applies ecological principles in an effort to return degraded ecosystems to conditions as similar as possible to their natural state.

Relate the following words: phosphorus, algal bloom, bacteria, hypoxic, dead zone:

Aquatic systems do not contain much phosphorus, so even a small amount of phosphorus inputs from fertilizer runoff can cause a rapid increase in the algal population, which is a process known as an algal bloom. As the algae die, decomposition takes up large amounts of oxygen causing the water to become low in oxygen, also known as hypoxic. If this low-oxygen area begins to kill aquatic animals, it becomes a dead zone.

Distinguish among the following words: atmosphere (including troposphere and stratosphere), hydrosphere, and lithosphere.

Atmosphere: The gasses surrounding the Earth. Troposphere: The lowest part of the atmosphere contains most water vapor. Stratosphere: Second layer of the atmosphere, contains the ozone layer. Hydrosphere: The combined mass of water on Earth. Components: oceans, freshwater, surface and groundwater, glacier water, and atmospheric water vapor. Lithosphere: The outer part of the earth- the crust and the upper mantle.

What are biogeochemical cycles?

Biogeochemical cycles involve cycles of biological, geological, and chemical processes because of the movement of matter within and between ecosystems.

List at least four major impacts humans have on the carbon cycle

Burning of fossil fuels, cellular respiration, reducing deforestation, and reducing the amount of industrial practices that release carbon.

Write out the equation for photosynthesis in both chemical formulas and word format. What is the overall goal of photosynthesis?

CO2+H2O=C6H12O6. Carbon dioxide and water are converted into glucose through the process of photosynthesis. The goal of photosynthesis is to feed autotrophs and create oxygen for other organisms.

List a general importance of calcium, magnesium, and potassium. Why might more soils be potassium-deficient rather than deficient in magnesium and calcium?

Calcium, magnesium, and potassium play important roles in regulating cellular processes and in transmitting signals between cells. Calcium and magnesium are strongly attracted to the soil particles, while potassium has a weaker attraction, making potassium more easily removed from the soil.

Write out the equation for cellular respiration in both chemical formulas and word format. What is the overall goal of cellular respiration?

Cells convert glucose and oxygen into energy, carbon dioxide, and water. C6H12O6 + 6O2 → 6CO2 + 6H2O. The goal of cellular respiration is to create energy for organisms.

What is ecological efficiency?

Ecological efficiency is the proportion of consumed energy that can be passed from one trophic level to another.

What is ecological restoration?

Ecological restoration is the growing interest in restoring damaged ecosystems.

First law of thermodynamics

Energy can be transferred and transformed, but it cannot be created or destroyed.

List two ways that humans have impacted the nitrogen cycle.

Excessive use of nitrogen-containing fertilizers and burning fossil fuels.

What does GPP stand for? Explain what GPP is.

Gross Primary Productivity. This is a measure of the total amount of solar energy that the producers in the system get through photosynthesis.

List two ways in which humans negatively affect the sulfur cycle. What are the impacts of that human disturbance?

Humans add more sulfur to the atmosphere by burning fossil fuels and mining metals. The impacts of human disturbance are that they increase acid rain which can result in negatively affected aquatic and terrestrial ecosystems.

What happens to matter in an ecosystem? How does this relate to the Law of Conservation of Mass?

In an ecosystem, matter cycles between different forms and locations. This relates to the Law of Conservation of Mass because as the law states, no matter is lost nor created, but instead used in different ways.

Relate a trophic pyramid to a biomass pyramid.

In both pyramids, biomass is lost as one moves up trophic levels; however, trophic pyramids tend to have similar proportions across ecosystems.

mineralization

In this process bacteria convert organic nitrogen into inorganic nitrogen

What was phosphorus often added into prior to 1994? What is it still sometimes an additive in (in the US)?

Laundry detergent. Dishwashing detergents are sometimes still an additive.

Use the second law of thermodynamics to explain why many impoverished people in developing countries live mostly on a vegetarian diet

Many people in developing countries may not have access to or the ability to purchase meat. This could result in many impoverished people choosing a vegetarian diet, as they must find other ways to get the energy they need from food.

Write an equation relating NPP and GPP.

NPP= GPP- Respiration by producers.

biogeochemical cycle (nutrient cycle)

Natural processes that recycle nutrients in various chemical forms from the nonliving environment to living organisms and then back to the nonliving environment. Examples include the carbon, oxygen, nitrogen, phosphorus, sulfur, and hydrologic cycles.

What does NPP stand for? Explain what NPP is.

Net Primary Productivity. This is the energy captured minus the energy respired by producers.

List two uses for nitrogen in the body.

Nitrogen is used for protein synthesis and is also a building block of DNA.

third law of thermodynamics

No system can reach absolute zero

Discuss one of the most studied watersheds in the last 50 years. Explain why this watershed is an appropriate one to study and what findings have come of it.

One of the most studied watersheds is the Hubbard Brook watershed in New Hampshire. Due to the watershed's bedrock at the bottom, there is no percolation meaning that any water that leaves is leaving through evapotranspiration and or runoff, making it a great watershed to study. Due to the location and way of the watershed, it has led researchers to many answers regarding biochemical cycles. For example, one huge and well-known test done at Hubbard was the experimental forest where they tested clearcutting and its effects on the area. This led the researchers to many discoveries about biogeochemical cycles and therefore, makes the watershed an extremely important research area.

List the following in order from smallest to largest, define each and then give an example of each: biosphere, ecosystem (AKA biome), population, organism, and community.

Organism ( an individual in a population), population ( a group of individuals within a species), community ( a group of two or more species), ecosystem ( a community within interacting biotic and abiotic factors), and biosphere ( all parts of the earth).

detritivores

Organisms that eat dead organic matter

ecological efficiency

Percentage of energy transferred from one trophic level to another in a food chain or web

Is phosphorus a limiting nutrient? Relate phosphorus to nitrogen in this regard.

Phosphorus is a limiting nutrient just like nitrogen, and phosphorus is the second most important nutrient for successful agricultural yields, following nitrogen. Additionally, both nitrogen and phosphorus are used in fertilizer.

Describe characteristics of typically very productive ecosystems.

Plenty of sunlight, lots of available water and nutrients, and warm temperatures- these types of ecosystems are where producers thrive the most.

fermentation

Process by which cells release energy in the absence of oxygen

chemosynthesis

Process by which some organisms, such as certain bacteria, use chemical energy to produce carbohydrates

Put the following trophic levels in order in a food chain: primary consumer, tertiary consumer, producer, secondary consumer.

Producer, primary consumer, secondary consumer, and tertiary consumer.

anerobic respiration

Respiration that does not require oxygen

aerobic respiration

Respiration that requires oxygen

Distinguish among scavengers, detritivores, and decomposers. Give examples of each.

Scavengers: Organisms that eat dead animals. Ex: vultures. Detritivores: Organisms that specialize in breaking down dead tissues and water products. Ex: dung beetles. Decomposers: Organisms that finish the breakdown process by converting organic matter into small elements that can be recycled back into the ecosystem. Ex: fungi and bacteria.

List at least three reasons why when a cheetah eats a gazelle not all of the energy is passed to the cheetah.

Some parts of the gazelle are not digestible. Some of the gazelle is used for the cheetah's growth and reproduction. Parts of the gazelle are lost as heat.

How is a standing crop different than NPP? Give an example to support your answer.

Standing crops represent the amount of biomass present in an ecosystem at a particular time, while NPP measures the rate of energy production over a span of time. Example: Slow-growing forests that have low productivity because the trees add only a small amount of biomass through growth and reproduction each year.

What is the intermediate disturbance hypothesis? Give one example that demonstrates this hypothesis.

The intermediate disturbance hypothesis says that ecosystems experiencing intermediate levels of disturbance will favor a higher diversity of species than those with high or low disturbance levels. An example of the intermediate disturbance is the number of algal species observed in response to a mixed number of present snails because when many snails are present, there is a low diversity of algal species. However, when an intermediate number of snails are consuming algae, the snails cause an intermediate amount of disturbance.

optimum range

The range of environmental conditions over which an organism performs best and can reproduce.

genetic diversity

The range of genetic material present in a gene pool or population of a species.

What is the range of tolerance for an abiotic factor?

The range of tolerance is the range of abiotic factors in which a species can survive. The larger the range, the more places the species can survive.

zone of stress

The range of values of an abiotic factor that an organism can survive but are not optimal.

Distinguish between ecosystem resistance and ecosystem resilience. Give an example of each.

The resistance of an ecosystem is a measure of how much a disturbance can affect the energy and matter flow. Example: when a small fire kills some animals in an ecosystem and aids other species. This allows the aided species to thrive and reproduce more, making an ecosystem more resistant to those fires. On the other hand, resilience is the rate at which an ecosystem returns to its original state after a disturbance. Example: If a severe drought eliminates half the species in an area, a highly resilient ecosystem's energy flow might return to normal in the following year. However, in a less resilient ecosystem, the flows of energy and matter might not return to their pre-drought conditions for many years.

What would happen to an ecosystem if all its decomposers and detritus feeders were eliminated?

There would be no way to recycle organic matter, and the world would fill up with dead organisms.

List the top three aquatic ecosystems in terms of NPP. Then list the bottom three aquatic ecosystems.

Top: Swamps and marshes, coral reefs, and salt marshes. Bottom: Lakes and streams, continental shelf, and the open ocean.

List the top three terrestrial ecosystems in terms of NPP. Then list the bottom three terrestrial ecosystems.

Top: Tropical rainforests, tropical seasonal forests, and temperate forests. Bottom: Tundra, desert scrub, and extreme desert.

What is transpiration? Compare and contrast transpiration and evapotranspiration.

Transpiration is a process in which plants release water from their leaves into the atmosphere. Evapotranspiration is a very similar process as it takes transpiration and combines it with evaporation in the air.

limiting factor/limiting nutrient

a nutrient required for the growth of an organism but available in a lower quantity than other nutrients

disturbance

an event, caused by physical, chemical, or biological agents, resulting in changes in population size or community composition

NPP allows us to ......... the ......... of different ecosystems.

compare, productivity.

Intermediate disturbance principle

local species diversity is maximized when ecological disturbance is neither too rare nor too frequent.

hypoxic

low oxygen

denitrification

process by which bacteria convert nitrates into nitrogen gas

Another name for an autotroph is a Another name for a heterotroph is a Distinguish between autotrophs and heterotrophs.

producer, consumer, Autotrophs make their own food through photosynthesis while heterotrophs are unable to produce their own food. Instead, heterotrophs get their energy by consuming other organisms.

lithosphere

the rigid outer part of the earth, consisting of the crust and upper mantle.

assimilation

the social process of absorbing one cultural group into harmony with another

leaching

the transportation of dissolved molecules through the soil via groundwater

Second law of thermodynamics

when energy is transformed, the quantity of energy remains the same, but its ability to do work diminishes

zone of intolerance

zone where organisms cannot survive