Biogeochemical Cycles Biogeochemical Cycles Matter can neither be

Biogeochemical Cycles

Biogeochemical Cycles �Matter can neither be created or destroyed �It cycles through the biosphere. �As it cycles, it follows certain characteristic pathways �These pathways are called “Biogeochemical Pathways” �Bio = Life �Geo = Earth

Biogeochemical Cycle �Biogeochemical cycle: cycle of transferring nutrients from the environment, to an organism, and back to the environment Biogeochemical Cycles

Review: Energy Pathway �Energy enters an ecosystem in the form of sunlight �Eventually all energy is lost as heat �Biosphere requires a continual flow of new energy Sun Energy Loss

Input energy Biogeochemical Ecosystems are OPEN SYSTEMS. Energy and matter can flow in and out of system Cycles Energy Lost

Nutrient Recycling �On Earth there is finite supply of nutrients �Energy cannot be created or destroyed �To maintain balance, matter is recycled �Main elements: �Carbon, Hydrogen, Oxygen, Nitrogen �Main organic compounds: �Carbohydrates, lipids, proteins, nucleic acids Cell energy Energy storage Cell structure Genetic material

The Main Cycles �There are 4 major cycles to understand �Hydrological Cycle or Water Cycle �Carbon/Oxygen Cycle �Nitrogen Cycle �Phosphorus Cycle

The Water or Hydrological Cycle

Water Cycle �Water cycle path of water through the environment �From the earth to the atmosphere and back to the earth �Importance of water: �Absorbs and releases water = stable global weather patterns �Medium for reactions �Solvent � 60% of cell’s mass

Properties of Water � All living things need water � Water can be found in the biosphere in three states” 1. 2. 3. Solid (snow or ice) Liquid Gas ( vapour) � Water is continuously entering and leaving living systems

Polar Molecule �The attraction of water molecules. �One end of the molecule is positive, and other end is negative.

Hydrogen bonding �Attraction between slightly negative O and slightly positive H

Higher Boiling and Freezing �Takes more energy to make molecules let go of each other and change state �Liquid to gas �Solid to liquid

Hydrological Cycle Terms – Abiotic Components �Precipitation �atmospheric water falling in the form of �rain, snow, sleet, hail, dew. . . �Groundwater �water on the surface or just below the surface �lakes, rivers, oceans, aquifers, artesian wells… �Evaporation �water that has been heated by the sun rises as water vapor. �Condensation �vapor into droplets when cooled

More Hydrological Cycle Terms – Biotic Components �Cellular Respiration �the process in which living organisms convert the energy of sugars into energy used by body processes �Transpiration �the loss of water through the leaves of plants

Water’s Role �Moves from atmosphere to earth through precipitation �Surface runoff and groundwater flows to other bodies of water �Water enters the atmosphere through transpiration and evaporation

Role of living things �Plants: �Return water to the atmosphere through transpiration and evaporation �Animals: �Return water to the atmosphere through gas exchange, perspiration, evaporation, excretion, cellular respiration

Using hydrological cycle terminology label this diagram in your notes on page 13

Water Cycle 1. Water in clouds (condensation) 2. Rain and snow (precipitation) 3. Water drains into river and soil (run off) 4. Water taken up by plants and animals (through groundwater) 5. Water loss by transpiration 6. Water loss by respiration 7. Evaporation

Water Beneath the Soil �Freshwater comes from two sources �Ground water: rain fall seeps into the soil and filters downwards due to gravity �Surface water: precipitation that collects above ground in lakes and rivers

Ground water is created by, �Percolation: water filters downward between the particles in the soil �Eventually the water fills the lower level of the soil and a water table forms above impenetrable bedrock or clay �As water seeps downwards it dissolves organic matter and minerals called leaching

Acid Deposition �Industrial plants burn metals & fossil fuels. �When they undergo combustion, sulfur is released into the air �This is usually in the form of SO 2 �Some industrial plants as well as automobiles also release nitrogen wastes �usually nitrous oxides (NOx)

So. �Sulfur dioxide and nitrous oxides can condense with water vapor in the air to form … �tiny droplets of acid. �This is called acid rain!! �Not all the SO 2 or NOx combine with H 2 O(g). �Some will circulate in the air and fall to the ground in the form of dry acid deposition.

Water Cycle Song �https: //www. youtube. com/watch? v=T 05 djitk. EFI

Water Filtration �http: //www. ted. com/talks/michael_pritchard_invents _a_water_filter

The Carbon Cycle

The Carbon Cycle �Also called the Carbon-Oxygen Cycle. �Refers to the flow of CO 2 through the biosphere. �The main part of this cycle involves the interrelation between respiration and photosynthesis. 6 CO 2 + 6 H 2 O 6 O 2 + C 6 H 12 O 6

The Carbon Cycle 6 CO 2 + 6 H 2 O 6 O 2 + C 6 H 12 O 6

The Carbon Cycle 6 CO 2 + 6 H 2 O 6 O 2 + C 6 H 12 O 6 � The products of this reaction are used by plants in photosynthesis to produce more glucose and oxygen.

The Carbon Cycle �Carbon dioxide is also released by the activities of : �Volcanoes �Automobiles �Combustion of any source

The Carbon Cycle

�Human impact: �burn excess fossil fuels �Use up forests �Result is more CO 2 added to atmosphere �Leads to the greenhouse effect �Greenhouse effect: �Heat blocking action of gasses in the atmosphere �Short waves converted to long – unable to escape atmosphere

Earth’s Heat Retention Albedo The extent to which a surface reflects light. E. g. snow, dirt, The higher the albedo, the more reflective the surface.

Greenhouse Gasses Name of Gas Chemical Formula Source Carbon Dioxide CO 2 Fossil fuels Methane CH 4 Bacteria decay, farts Nitrous Oxide N 2 O Fertilizers, animal wastes CFC’s Styrofoam, accelerants

�Humans continue adding excess amounts of CO 2 �Since 19 th century, levels have increased 25% �Possible increase in global temperature

�Effects: �Melting ice caps �Sea levels to increase – flooding �Change in climate patterns �More/less rainfall �Large impact on agriculture �Natural vegetation could change �Some say that oceans are a large sink for CO 2 �Solutions?

Tesla

Petrol vs Electric Mercedes SLS AMG �https: //www. youtube. com/watch? v=5 g. FGX 43 vub. M

FCX Clarity

Ozone Layer �Protects earth from UV radiation �~ 99% of UV radiation is screened and never reaches surface �Ozone holes: �Above the poles (N & S) �Increase in skin cancer and eye problems �Major cause? � CFC’s

�CFC’s released in sprays and as a waste product �When in upper atmosphere, Chlorine reacts with ozone and breaks it down �CFC’s stay in atmosphere for a very long time �May continue to break down ozone layer �Solution?

The Nitrogen Cycle

The Nitrogen Cycle �The complex cycling of nitrogen between organisms and the environment. �The air is 79% nitrogen. �The main component of most fertilizers is a nitrogen compound.

Nitrogen and Plants �Nitrogen is a chemical that plants need to grow well. Plants get nitrogen through �Nitrates (NO 3 ): a group of nitrogen containing compounds that are readily absorbed by the roots of plants �(that’s good. )

Nitrogen and Animals �Nitrogen is also needed for the construction of proteins and nucleic acids �Muscle tissue �Hair �Bones �Cell parts �DNA �RNA

Nitrogen Usage �Nitrogen is usually utilized in life in the form of nitrates. �There are 2 main ways atmospheric nitrogen can be converted into useful forms. 1) Lightning 2) Legumes

Method #1 -- Lightning �Lightning can force nitrogen and oxygen together to form nitrates �these will fall with precipitation and be absorbed by plant roots. �The plants will change these into their own proteins. �Animals eat the plants and reorganize those proteins into the ones they need.

Method #2 -- Legume �Legumes are members of the bean family and include: clover � Alfalfa… � �Have nitrogen fixing nodules on their roots. �These can convert atmospheric nitrogen into nitrates. �Legumes can utilize atmospheric nitrogen.

Legumes

Dr. Death speaks… �After an organism dies, it decays. �Decaying matter which contains nitrogen produces ammonia. �Ammonia will degrade into nitrites. �Nitrites will degrade into nitrates. �The nitrates will now re-enter the cycle.

Nitrogen Cycle �Some bacteria will actually convert the nitrates back into atmospheric nitrogen. �Denitrifying bacteria. �These bacteria do not need oxygen -- anaerobic respiration.

Atmospheric pool of nitrogen Lightning Fertilizers Nitrogen-fixing bacteria in root nodules of legumes Why me?

1. Atmospheric pool of nitrogen 2. Nitrogen-fixing bacteria in root nodules of legumes 3. Fertilizers 4. Soil nitrate 5. Nitrate take up by plant roots 6. Plant and animal proteins 7. Dead organisms 8. Decomposers 9. Nitrate bacteria 10. Nitrite bacteria 11. Denitrifying bacteria 12. Lightning

The Phosphorus Cycle

Phosphorus Cycle �Phosphorus is a nutrient required by all living things. �Component of bones and teeth �DNA �ATP �Phosphorus Cycle is simpler than the carbon or nitrogen cycles because it does not involve movement through the atmosphere.

The Phosphorus Cycle �Two methods of P recycling: �geological (abiotic) �living organisms (biotic)

Long Term Cycle �Most common form: a part of rocks �Properties: �soluble - dissolve in water �Phosphates dissolve in water—erosion carries them from land to streams and rivers and then finally to the oceans �Oceans sediments may be thrust upward and once again form land through geological activity

Long Term Cycle

Short Term Cycle �Phosphates in water also enter the food chain through photosynthetic organisms �Decomposition of dead organisms soluble phosphates are absorbed by plants and used during photosynthesis �Plants are eaten by animals