Water, Carbon, and Nitrogen Cycles of Matter Water, Carbon, and Nitrogen

The Water Cycle

Water from oceans, lakes, and other bodies of water re-enters the atmosphere through evaporation.

Precipitation Water that has condensed in the air forms clouds. Drops fall to Earth and accumulate in oceans and lakes. Precipitation

Plants and animals return water to environment through transpiration. Animals return water to ground and bodies of water through urine. Transpiration

The Water Cycle Create a key to label the diagram. Add arrows to show the directionality of the water through the system. Draw an example of transpiration and in your diagram and label it in the key. Adapted from http://education.jlab.org/reading/water_cycle.html The Water Cycle

The Water Cycle Key Sun (energy) Cloud Evaporation Precipitation Ocean Transpiration The Water Cycle Key

The Sun __________water from oceans and lakes The Sun __________water from oceans and lakes. As the air rises, it __________. The water __________into tiny droplets of water. The droplets crowd together and form a __________. Wind blows the cloud toward the land. The tiny droplets join together and fall as __________to the ground. The water soaks into the ground and __________in rivers and lakes. The __________never ends and starts again. The Water Cycle

The Sun evaporates water from oceans and lakes The Sun evaporates water from oceans and lakes. As the air rises, it cools. The water condenses into tiny droplets of water. The droplets crowd together and form a cloud. Wind blows the cloud toward the land. The tiny droplets join together and fall as precipitation to the ground. The water soaks into the ground and collects in rivers and lakes. The cycle never ends and starts again. The Water Cycle

The Carbon Cycle

Plants use CO2 from the atmosphere to make high-energy carbon molecules. Photosynthesis

CO2 is released through aerobic respiration (breathing, for example).

CO2 is exchanged between the air and water. Gas Exchange

When organisms die and decay, the carbon molecules in them enter the soil. Microorganisms break down the molecules, releasing CO2. Decomposition

Remains of dead organisms are converted into fossil fuels (over millions of years!) Combustion of fossil fuels and wood releases CO2. Pollution

Label the diagram using the numbers in the notes to indicate each step in the cycle. The Carbon Cycle

The Nitrogen Cycle

Nitrogen In the Air Lightning and bacteria convert atmospheric nitrogen into nitrates (NO3) and ammonia (NH3) The air we breathe is about 78% nitrogen in the form of N2 gas and about 21% oxygen in the form of O2 gas.

Nitrogen in Plants Plants receive their nitrogen through the soil, water, and air.

Nitrogen in Animals When animals die their decomposing bodies add the nitrogen back into the soil. Animals also add nitrogen to the soil through feces. Animals receive nitrogen from the plants they eat or from other animals that eat plants.

Nitrogen compounds break down into gas and return to air. Return to Atmosphere

Nitrogen in Soil and Water Runoff of nitrates in fertilizers enters groundwater and soil. Denitrification is an important step in the nitrogen cycle where nitrogen is released back into the atmosphere. Nitrates are water-soluble and leach out of the soil, flowing into groundwater and collecting in lakes and wetlands.

Man and Pollution Man made pollution such as vehicle exhaust, power-plant exhaust, man made fertilizers and large-animal feeding operations are all sources of nitrogen emissions. Nitrous Oxide from burning fossil fuels falls as Nitric Acid in rainwater.

Label the diagram using the numbers in the notes above to indicate each step in the cycle. Add examples for 4 and 6. The Nitrogen Cycle