Transcript Matter Cycles

Matter
Cycles
matter
Matter Cycles
• The Law of Conservation of Matter states
that matter is neither created or destroyed
• In biological systems, this also holds true
• We will be focusing on four matter cycles, also
called nutrient or biogeochemical cycles
• These are the Carbon, Water (hydrological),
Nitrogen and Phosphorus cycles
The Carbon Cycle
The Carbon (C) Cycle
• Even though it cycles we are going to start in
the atmosphere
• CO2 (carbon dioxide) in the atmosphere is
picked up by photoautotrophs and turned into
sugars
• These sugars support the building of C
containing molecules that make up living
organisms
• Another organism eats the plants, transferring
the C to the next organism
The Carbon (C) Cycle
• This C may be passed on to another organism
if it gets eaten
• CO2 is reenters the atmosphere by cellular
respiration from most organisms
• Dead organisms and waste decomposes and
more CO2 is reenters the atmosphere
• Fossil fuels are underground stores of C, when
dug up are burned (combustion) as
petroleum, natural gas or coal; they add
additional C as to our environment as CO2
• Excess CO2 is absorbed in bodies of water
The Carbon (C) Cycle
• CO2 is an important Greenhouse gas helping
keep the planet at a relatively stable
temperature
• Excess burning of fossil fuels by industry and
transportation has increased the amount of
ground level and atmospheric C on our planet
and may be accelerating climate change.
The Water Cycle (hydrological)
The Water Cycle (hydrological)
• Evaporation-water enters the atmosphere
• Precipitation-water condenses and leaves the
atmosphere as rain, sleet or snow and ends up on
land and can –
– Runoff into surface water or
– Infiltrate (or percolate) into land as groundwater or
– Freeze and accumulate as ice
• Or ends up in the ocean or other surface water
• Transpiration –water leaves plants and enters the
atmosphere
The Water Cycle (hydrological)
• Humans interrupt the water cycle by
• Over pumping ground water
• Creating many impervious surfaces (buildings,
concrete and asphalt) so that water cannot
reenter the ground and refill ground water
• Polluting available surface and ground water
• Building dams
• Growing thirsty plants where they are not
adapted to grow
The Water Cycle (hydrological)
The Nitrogen Cycle
The Nitrogen Cycle
• 78% of the atmosphere is Nitrogen, N2, is the
major source of this vital element which is
essential to make proteins in all living
organisms
• There is ONLY one kind of organism that can
take N2 from the atmosphere and they are
called N fixing bacteria
• These soil dwelling N fixing bacteria then
make N available to plants
The Nitrogen Cycle
• Plants use the N, now as nitrate or ammonium
and make proteins
• These plants are eaten and the N as protein is
passed on to the consumer
• Lightning strikes can also fix atmospheric N2 in
the soil
• N2 can return to the atmosphere by denitrifying
bacteria in wet soil
• N can also returned to the soil by
decomposition of waste or dead organisms
The Nitrogen Cycle
• Humans impact the N cycle by
• Manmade fertilizer high in N
• Burning of petroleum by internal combustion
engines (cars) produces large amounts of N
compounds that cause acid rain by forming
nitric acid when mixing with water in the
atmosphere
The Phosphorus Cycle
The Phosphorus Cycle
• Unlike all the other matter cycles,
Phosphorus, P, NEVER cycles through the
atmosphere
• P is important both as part of DNA and cell
membranes
• P is MOSTLY found in rock
• P is an important limiting factor in plant
growth
The Phosphorus Cycle
• P is picked up by plants from the soil
• The plants are eaten and P is obtained by the
consumers from eating the plants
• Then the P goes to the next consumer
• P renters the ground by waste or
decomposition
• Weathering of rock is vital for the P cycle as is
the water cycle for the movement of P
The Phosphorus Cycle
• Humans impact the P cycle by adding large
amounts of inorganic fertilizer high in
phosphorus which enters surface and ground
water
• Farm animal waste from large farms is high in
P and can also enter the water cycle
• These large amounts of P can cause
eutrophication, rapid and large growth plants
and algae, of bodies of water which chokes
out other aquatic life forms
Cycles Wrap-up
• biogeochemicals cycles video