Ecology Unit Learning Goal #2: Explain relationships between matter cycles and organisms.

Cycles of Matter  Unlike the one-way flow of energy, matter is recycled within and between ecosystems.

The Water Cycle

The Water Cycle TTTThe water required by all living organisms moves between the ocean, the atmosphere, and the land. EEEEvaporation  liquid to a gas TTTTranspiration  water that enters the atmosphere by evaporating from the leaves of the plants. CCCCondensation  gas to a liquid PPPPrecipitation  The water that returns to the earth’s surface in the form of rain, snow, sleet, or hail. RRRRunoff  The precipitation that runs along the surface of the ground until it enters a river or stream. SSSSeepage  Water that seeps into the ground. RRRRoot Uptake  Water enters plants and starts the process over again.

Organisms and the Water Cycle  Producers – Take water from the soil through roots, then release it through leaves. This is called transpiration.  Consumers – Take in water from their food and from surface water supplies. They release it back into the environment through waste products, respiration, and give it off from their outer covering.  Decomposers – Release water into the atmosphere as they break down dead matter.

The Carbon Cycle

 Carbon is a key ingredient in living tissue. –Four main types of processes move carbon through its cycle:  Biological processes –such as photosynthesis, respiration, and decomposition  Geochemical processes –such as erosion and volcanic activity  Mixed biogeochemical processes  Human activities –such as mining, cutting and burning forests, and burning fossil fuels The Carbon Cycle

The Carbon/Oxygen Cycle  Producers – Take in carbon dioxide (CO 2 ) from the atmosphere and use it to make carbon compounds like carbohydrates through the process of photosynthesis: CO 2 + H 2 O  C 6 H 12 O 6 + O 2 CO 2 + H 2 O  C 6 H 12 O 6 + O 2 (glucose) (glucose)

 Consumers – Eat food made by the producers to get carbon compounds for energy. Take in oxygen (O 2 ) to use in cellular respiration: O 2 + C 6 H 12 O  CO 2 + H 2 O + (Energy)  Decomposers – Take in and give off O 2 and CO 2 as do other consumers.  Carbon compounds are also stored in the earth as fossil fuels when plant and animal matter is buried and compressed over long periods of time. –CO 2 is then released when these fuels are burned. –Some also comes from earth processes like volcanoes.

The Nitrogen Cycle

The Nitrogen Cycle  The Earth’s atmosphere is 78% nitrogen gas.  All organisms need nitrogen compounds to build muscle and DNA along with other biological molecules.  Atmospheric nitrogen must be converted to a form that is usable to organisms  Some types of soil bacteria can convert nitrogen in the air to a usable form for plants. This is called nitrogen fixation.

 Producers – Take in nitrogen compounds from the soil and use them to build biological molecules.  Consumers – Get their nitrogen from eating plants and other types of organisms.  Decomposers – Release nitrogen compounds back into the soil. Other types of bacteria convert the nitrogen back into nitrogen gas (denitrification).

The Phosphorus Cycle

The Phosphorus Cycle  Phosphorus is the only important biological element that does not occur as part of atmospheric gases.  It’s original source is in the earth’s crust as part of rocks.  It is released into the soil through the process of erosion.  Phosphorus is an important component of DNA and proteins as well as other biological molecules

Producers – Pick up phosphorus compounds from the soil. Consumers – Get their phosphorus from their food. Decomposers – Release phosphorus compounds back into the soil.

AAAAn imbalance of any of the nutrients can limit an organism’s growth.