Download Nitrogen cycle.

Natural Cycles
• Only few of the known elements found in the upper
crust of the Earth in water or the atmosphere are
abundant in tissues of living organisms like carbon,
hydrogen, oxygen, or nitrogen.
• Circular flow of elements from living organisms to
nonliving matter is the elemental cycle.
The Carbon Cycle
• Carbon is the most abundant element in living
organisms
• In the absence of water, nearly half of dry matter in
bodies of animals or humans consists of carbon
• The Carbon Cycle occurs as carbon atoms flow
continuously from living organisms to the
atmosphere, the oceans, and the soil
The Nitrogen Cycle
• Nitrogen fixation also occurs naturally in the
atmosphere when lightning strikes
• Nitrates are released from animal wastes and
decaying plants and animals
The Water Cycle
• Water is 70% of plant and animal weight
• Water controls the temperature of organisms and is a
nutrient solvent
• Water dissolves nutrients and carries them to tissues
that need them
• Water stores heat and maintains constant
temperature in the environment
CO2 and Global warming
• Research has demonstrated that sea water
algae are capable of removing large amounts
of CO2 from the atmosphere.
• Adding iron as a nutrient to the water surface
can simulate the algae growth.
• Some scientist worry that promoting algae
growth on a massive scale could upset the
balance of the ecosystems of the oceans.
The Nitrogen Cycle
• The circular flow of Nitrogen from free gas in
the atmosphere to the Nitrogen compounds
such as nitrates in the soil and back to the
atmospheric Nitrogen is know as the Nitrogen
cycle.
• Nitrogen makes up about 80% of the air
supply.
• Odorless gas that cannot be used by plants or
animals.
The Nitrogen Cycle cont.
• Must be combined with oxygen, or other
elements before it becomes available as a
nutrient for living organisms.
• Nitrogen Fixation- a process by which nitrogen
gas is converted to nitrates.
• Nitrogen – fixing bacteria- are able to convert
nitrogen gas to nitrates.
• Clover, beans, peas, and other legumes are able
to make their own nitrogen fertilizer.
• Types of blue/green algae and fungi also are
capable of nitrogen fixation.
The Nitrogen Cycle Cont.
• Several Industrial processes also convert Nitrogen gas to
nitrates.
• One Process converts the gas to ammonia as a by product
of steel production.
• Ammonia can also be obtained directly from natural gas.
• It is then converted to a form of nitrate that can be used for
fertilizer.
• Denitrification occurs when some forms of bacteria come
into contact with nitrates.
• Similar processes occur when nitrates are carried by runoff
water into surface water, which constantly exchanges
nitrogen with the atmosphere.
The Water Cycle
. Water is one of the most important recourses in the
environment
. Provides living environment and helps growth of
plants
. 70% of the weight of living plants and animals is
water
. Need water to survive
. Water stores heat and helps maintain a more
constant temperature
. Soil break down from the water flow
. Water moves in forms of rain or snow, from the ocean
to the atmosphere, to the soil, to the streams and rivers
and then back to the ocean
.Solar energy and the force of gravity is how it drives the
cycle.
. Source of heat causes water to evaporate from the
ocean is solar energy.
. More water enters the atmosphere by evaporating
from the soil and plant surfaces
. Transpiration is when plants give up large amounts of
water to the atmosphere.
. Plants lose water through pores in their leaf surfaces
. Their pores open when it gets hot and they close when
it is cool.
.transpiration can create a negative pressure that will
move water and nutrients into the plants from the soil
. Mammals control their body temp. by releasing water
through their skin pores in their sweat or perspiration
. Moisture is released to the atmosphere from breathing
out from your lungs
. The moisture builds up in the atmosphere and forms
clouds
. Clouds release water down to the Earth’s atmosphere