Earth's Systems
Which Earth system includes all living organisms?
Biosphere
What process occurs when liquid water changes into water vapor?
Evaporation
What is a watershed?
An area of land where water drains to a common body of water.
What process removes carbon dioxide from the atmosphere and stores carbon in plants?
Photosynthesis
What process changes atmospheric nitrogen into a form that can eventually be used by plants?
Nitrogen Fixation
Which Earth system includes rocks, soil, minerals, and Earth's physical landforms?
Geosphere
What process occurs when water vapor cools and changes into tiny liquid water droplets?
Condensation
What usually happens to water when it falls on land that has very little vegetation and does not absorb water easily?
More water becomes surface runoff.
What process releases carbon dioxide when organisms break down food for energy?
Cellular Respiration
Why do farmers add nitrogen fertilizer to agricultural fields?
To provide plants with usable nitrogen needed for growth.
A plant takes in carbon dioxide from the air and water from the soil. Which two Earth systems are interacting?
Atmosphere & Geosphere
A puddle disappears after sitting outside on a warm, sunny day. What happened to the water?
It evaporated & entered the atmosphere as water vapor.
In your watershed model, what would you expect to happen to runoff if you increased the slope of the land? Explain why.
Runoff would generally increase or move faster because water flows downhill more quickly and has less opportunity to infiltrate.
Why are plants important to the carbon cycle?
They remove carbon dioxide from the atmosphere through photosynthesis and store carbon in their biomass.
Why can't most plants simply use the nitrogen gas that makes up much of Earth's atmosphere?
Atmospheric nitrogen gas must first be converted into usable nitrogen compounds/forms.
A forest is removed from a hillside. Predict one way this could affect the biosphere and one way it could affect the hydrosphere.
Biosphere: habitat/living organisms are affected. Hydrosphere: more runoff or less water infiltration could occur.
A large amount of rain falls on an area where the soil is already saturated. Would you expect more infiltration or more surface runoff? Explain.
More surface runoff because the soil cannot absorb much additional water.
Two watersheds receive the same amount of rain. Watershed A has lots of vegetation, while Watershed B has many agricultural fields and less vegetation. Which watershed would likely have more surface runoff? Explain.
Watershed B. With less vegetation, there is generally less interception and infiltration, so more water can flow over the surface.
A large amount of fossil fuel is burned. Predict what happens to the amount of carbon dioxide in the atmosphere and explain why.
Atmospheric carbon dioxide increases because burning fossil fuels releases stored carbon into the atmosphere.
A farmer applies more nitrogen fertilizer than the crops can use. What could happen to the extra nitrogen?
It could move through the soil and enter groundwater or surface water through runoff or leaching.
Explain how a change in one Earth system can cause changes in other Earth systems. Give a specific example.
Removing vegetation from land can increase runoff, affecting the hydrosphere, while also reducing habitat in the biosphere.
Explain how water can move from precipitation into groundwater and eventually return to surface water.
Water infiltrates into the ground, moves through soil/rock as groundwater, and can eventually flow into streams, rivers, lakes, or other surface-water systems.
Your watershed simulation showed that changing the landscape changed how water moved. Imagine a watershed with steep slopes, little vegetation, many agricultural fields, and a very large rainfall event. Predict what would happen to the amount and speed of runoff and explain two possible effects downstream.
Runoff would likely be greater and move more quickly. Possible downstream effects include increased flooding, erosion, sediment entering waterways, or increased movement of pollutants/nutrients into surface water.
Explain how photosynthesis and cellular respiration work together to move carbon through an ecosystem.
Photosynthesis removes carbon dioxide from the atmosphere and incorporates carbon into organic molecules. Cellular respiration breaks down those molecules and releases carbon dioxide back into the atmosphere.
A field receives too much nitrogen fertilizer before a heavy rain. Explain how this could affect both the nitrogen cycle and a nearby body of water.
Excess nitrogen could move with runoff into the water, adding nitrogen to the aquatic system and potentially causing problems such as excessive plant/algae growth and reduced water quality.