1. Nutrient Cycling

2. Essential Questions Why is nutrient cycling important? What are the four most important nutrients that ecosystems rely on? Describe the water cycle, phosphorous cycle, carbon cycle, and nitrogen cycle.

3. The Water Cycle

4. Life on earth depends on water, so it is constantly moving between the atmosphere and earth in different states of matter. Life on earth depends on water, so it is constantly moving between the atmosphere and earth in different states of matter. – Condensation: gas to liquid – Evaporation: liquid to gas – Precipitation: when water accumulates in the sky and falls to the ground – Transpiration:

5. The Water Cycle Transpiration: the loss of water vapor from plants Transpiration: the loss of water vapor from plants – Similar to sweating – Through transpiration, water cycles from the biotic to the abiotic parts of the atmosphere

6. The Carbon Cycle

7. ► All life on earth is based on carbon atoms which form complex molecules. ► Carbon dioxide enters the biotic parts of the biosphere through photosynthesis

8. The Carbon Cycle Carbon moves from plants to animals as herbivores consume plants Carbon moves from plants to animals as herbivores consume plants Carbon gets from animals to the soil as animals produce waste or die and decay Carbon gets from animals to the soil as animals produce waste or die and decay Carbon gets from animals to the air through respiration Carbon gets from animals to the air through respiration

9. The Nitrogen Cycle

10. Nitrogen is the most abundant gas in the atmosphere and is necessary for life Nitrogen is the most abundant gas in the atmosphere and is necessary for life Bacteria in the soil is needed to convert atmospheric nitrogen into compounds usable by plants Bacteria in the soil is needed to convert atmospheric nitrogen into compounds usable by plants ► Without bacteria, nitrogen could not be cycled from the biotic parts of the ecosystem to the abiotic parts of the ecosystem ► Lightening also fixes nitrogen for the ecosystem

12. The Phosphorous Cycle ► Detritus: waste or debris ► Phosphorous is found in:  Solids (rock)  Inorganic material (soil)  Organic material (plants and animals)  In solution

13. Essential Questions Why is nutrient cycling important? What are the four most important nutrients that ecosystems rely on? Describe the water cycle, phosphorous cycle, carbon cycle, and nitrogen cycle.