Matter Cycles through
Ecosystems.
• ALL ECOSYSTEMS NEED CERTAIN
MATERIALS.
• WATER CYCLES THROUGH
ECOSYSTEMS
• CARBON CYCLES THROUGH
ECOSYSTEMS
• NITROGEN CYLCLES THROUGH
ECOSYSTEMS
•
All Ecosystems Need Certain
Materials
Living things depend on their environment to meet their
needs.
• All of the materials an organism takes in are returned to the
ecosystem, while the organism lives or after it dies.
• The movement of matter through the living and nonliving
parts of an ecosystem is a continuous cycle. Matter never
leaves an ecosystem, it just changes form. The most
important cycles in ecosystems are: WATER, NITROGEN
and CARBON DIOXIDE.
Water Cycles thru Ecosystem
• Water is stored on Earth’s surface in Lakes,
Rivers, & Oceans. Also found underground, & a
lot in glaciers and polar ice sheets.
• Water is part of living things, and is constantly
moving through the environment: WATER
CYCLE.
• Water is made of Hydrogen & Oxygen; it
constantly is changing form (gas-liquid-solid).
Usually is gas in atmosphere (vapor), condenses
to fall as precipitation (snow, sleet, rain, hail),
and evaporates back to vapor into atmosphere.
• Animals release water vapor when breathing
(respiration) and plants do it through
transpiration.
Carbon Cycles thru Ecosystem
• Carbon is an element found in all living things. It is
through Carbon Dioxide gas (CO2) that carbon enters the
living parts of an ecosystem.
• Plants use CO2 to make sugar (in photosynthesis). Sugars
are carbon compounds important as a food source to
supply energy to organisms for growth & life. Energy is
released from food via respiration in organisms. Carbon
then gets cycled back into atmosphere as CO2 gas. When
living things die, the rest of carbon that makes up living
matter gets released.
• Earth’s ocean has a lot more carbon in it than air does.
CO2 is dissolved in water, used by algae to make food via
photosynthesis.
• Marine organisms also release CO2 through respiration
and carbon on the ocean floor when they die.
Nitrogen Cycles thru Ecosystem
• Nitrogen is another element important to life
that cycles thru ecosystems. 4/5 of air you
breathe is clear, colorless nitrogen gas. But we
can’t get it from the air, instead we get it from
plants.
• Plants absorb compounds of nitrogen with roots
from soil (also can’t get pure N from air).
• Lightning “fixes” or breaks apart pure nitrogen
into a form plants can use (it falls to ground
with rain). But most soil nitrogen comes from
“nitrogen-fixing bacteria” that live around roots
of plants & in oceans to change gas nitrogen
into usable nitrogen compounds.
• Also, decomposers break down dead matter in
oceans & soil to release nitrogen, used again by
living things.
• Some nitrogen goes back to atmosphere by
certain bacteria, releasing nitrogen gas.