Transcript Cycle

Cycles of Matter
• Matter moves in Biogeochemical cycles through
living systems, the Earth, the atmosphere, and the
oceans.
• These cycles connect biological, geological, and
chemical processes.
• 3 Biogeochemical cycles are:
water cycle
carbon cycle
nitrogen cycle
Water Cycle
• All living things require water to survive.
• Water is cycled between the ocean, the atmosphere and land.
Evaporation- process in which water changes from a liquid to
a gas.
Transpiration- process in which water evaporates from the
leaves of plants.
Cycle – Evaporation/Transpiration – Condensation – Precipitation- Runoff
(to rivers,streams, lakes, or ocean) – Seepage into ground water- Root
Uptake or to ocean. **Refer to diagram on page 75.
Carbon Cycle
• All living organisms need Nutrients to carry out essential
life functions.
• Nutrients are chemical substances that are cycled within &
between the ecosystems.
Carbon – is the key ingredient of living tissue.
**Refer to diagram on page 77.
4 types of processes that move carbon through its cycle:
• Biological processes – Photosynthesis, respiration, & decomposition.
Ex. CO2 is taken in by plants during photosynthesis & it is
given off by plants & animals during respiration.
• Geochemical processes – Erosion & Volcanic activity.
Ex. CO2 is released into the atmosphere and oceans.
• Mixed biogeochemical – Burial and Decomposition of dead organisms.
Under pressure they convert into fossil fuels &
stored underground.
Ex. Coal & petroleum
• Human Activities – Mining, cutting, & burning.
Ex. Burning forests release carbon dioxide into the atmosphere.
Nitrogen Cycle
•
All organisms require nitrogen to make amino acids, which in turn are used to
build proteins.
Nitrogen Fixation – process by which bacteria convert nitrogen gas in the
air to ammonia.
Process – Bacteria in the soil turn the ammonia into nitrates and nitrites. Producers use the ammonia,
nitrates and nitrites in the soil to make proteins. Consumers then eat the producers and reuse the
nitrogen to make their own proteins.
Denitrification – Dead organisms decompose returning nitrogen to the soil
as ammonia.
Process- Producers use the ammonia while bacteria converts nitrates into nitrogen gas which is released
into the air.
**Refer to the diagram on page 78.
Phosphorus Cycle
• Phosphorus is not very common in the biosphere and it
does not enter the atmosphere.
• It is found on land in rock / soil minerals and in ocean
sediments.
• Phosphorus is essential to living organisms because it
helps form molecules such as DNA and RNA
• Primary Productivity- the rate at which
organic matter is created by producers.
*controlled by the amount of available nutrients.
• Limiting Nutrient – a single nutrient that is
scarce or cycles slowly.
* because of this, farmers apply fertilizers