NATURAL BIOGEOCHEMICAL CYCLES

 

Energy Flow

First Law of Thermodynamics- Energy is _____________, not created or destroyed. It can only change in form.

Second Law of Thermodynamics- Energy transfers lead to the energy being in a less "_________", lower form.

Energy always degrades to a less concentrated level.

  • High Quality Energy: Very ___________, rich, intense, has high temperatures.
  • Low Quality Energy: dispersed, diffused, sporadic, ________ temperature

Conservation of Matter

Matter can't be created or destroyed, it just ___________ forms. In an ordinary chemical reaction, the total quantity of matter stays the __________.

 

Nutrient Cycles

Crash Course: Hydrologic and Carbon Cycles

Water Cycle: A ________ powered phenomenon whereby water moves through the environment in cycles

The circulation of water as it ______________ from land, water and plants (transpiration) and enters the atmosphere. There it condenses and precipitates back to earth and infiltrates underground (groundwater) by precipatation and _________ into rivers and oceans.

Water Cycle Gone Bad:

  • Water Withdrawl- dry wells, ____________ intrusion
  • Deforestation- Decreased infiltration and rain, increased runoff and __________
  • Pollution- Increased pollution in water ex. nitrogen from agriculture and cholera from ___________

Carbon Cycle: The building blocks of life

Carbon sinks or reservoirs:

1. Plant Matter:

Photosynthesis: Plants convert energy from sun along with carbon dioxide and water into _______ and oxygen within the chlorophyll.

Formula:

Only _______% of the sunlight ever makes it into the plant's tissue!

2. Animals and ocean life (especially in ___________, coral and fish skeletons)

3. Sedimentary rocks: limestone (the ____________ carbon storage of all) and carbon trapped in fossil fuels.

  • When bodies of once living organisms are buried and subjected to heat and pressure they become oil, ________ and gas (fossil fuels).

Carbon sources or how it is released:

1. Cellular Respiration: Oxygen consuming producers, consumers and decomposers break down complex organic compounds (____________, etc) and convert carbon back into carbon dioxide.

Formula:

  • The energy stored in the glucose bonds is transformed into ___________ and heat energy- it is not lost!
  • When oxygen is not present, anaerobic respiration creates methane!

2. Decay of ____________ material

3. Weathering of limestone

4. ______________ eruptions

The Carbon Cycle Gone Bad

Man is upsetting this cycle by __________ fossil fuels and tearing down (or burning) the jungles and woodlands of the world.

 

Nitrogen Cycle: Nitrogen is the _____________ component of air and yet plants can't directly acess it. Nitrogen is a critical ____________ ___________ for plant growth.

Crashcourse: Nitrogen and Phosphorus Cycle

  • A majority of nitrogen exists as an inert gas (_____) the in air (_____%), yet plants can’t take it up.
  • How can a plant access it?
    1. Nitrogen _________: Atmospheric nitrogen is "fixed" or transformed by bacteria living symbiotically on plant roots of _________ or in blue green algae (cynobacteria). The bacteria change the ______ into ammonia. (This form of nitrogen is _________ to most plants). Examples of legumes are peas, ________, soy, ________, and alfalfa.
    2. Nitrification- A different set of __________ break down the ammonia by combining it with oxygen to create nitrites and then finally _________. Plants can absorb ________ nicely.
    3. Assimilation- The plants then incorporate the nitrogen into _________ molecules (DNA, amino acids, proteins, etc!). Animals might then chow on the plants incorporating the nitrogen into their bodies.
    4. Ammonification- _______ plants and animals and their organic waste (like cow dung) convert their stored nitrogen back into ammonia with the help of ____________.
    5. Denitrification- Some of the nitrates can be converted back into atmospheric ____ through the help of (you guessed it)- ____________!

Nitrogen Cycle Gone Bad

  • Man is upsetting the natural balance of nitrogen by fixing nitrogen artifically to make chemical ___________.
    • These fertilizers are added to aquatic ecosystems by rain runoff or sewage overflows.
    • This in turn destroys the health of our fresh water streams and ponds by promoting rampant algae growth, which eventually renders the aquatic environment ____________!!! :(
  • Sewage leaks and spills from from large ____________ farms or poorly managed ___________ munipal sewage systems will create the same aquatic disaster as above.
  • Nitrogen oxides, a main component of acid rain, is also belched out of tailpipes of cars and trucks when they burn _______.
  • Burning plants also throws a lot of nitrogen into the air or soil

Phosphorus Cycle: A veeerrry sllloow cycle. It is a crucial element required for _________ transfer in organisms, bones and teeth. But it doesn't exist in in the atmosphere.

    • Soils contain very little phosporous ___________, so it is also major limiting factor for growth.
    • Phosphorous does not circulate as easily as nitrogen because it does not exist as a ______, but is released by weathering of phosphate rocks (fungus helps with this).
    • The phosphorous (PO4) is then dissolved in _________ and absorbed by plants. Animals that eat plants then pass the phosphorous along to the decomposers through their waste products, or when they die and decay. The decomposers then break down the phosphorous to the soil.
    • Dissolved phosphorus and phosphorus waste settles back into the __________ to become ________ again.
    • The largest storage reservoir of phosphorous is in ________.

Phosphorus Cycle Gone Bad

  • Man is creating an imbalance in phosphorous levels by mining ___________ (bird poop rich in phospates) and rocks for fertilizers and detergents.
  • P is also found in runoff from human and livestock ___________.
    • When sewage, fertilizers and detergents make their way into our fresh waterways, it causes massive ________ blooms and wide zones devoid of _______.
  • Clear cutting tropical forests decreases the amount of phosphorus available for whatever is growing in its place... unless ________________ is added.

Sulfur Cycle: Another slow cycle

    • Most sulfur is bound up inside _______ (like pyrite and gypsum) and is slowly released through weathering. In the oceans most of the sulfur is dissolved sulfate or buried deep in ocean sediments.
    • On a good day sulfur can become _________ through volcanic eruptions or deep-sea vents.
    • Sulfur is also released through bacterial breakdown, evaporation from water or decaying organisms.

Sulfur Cycle Gone Bad

  • Unfortunately, burning coal and other fossil fuels adds massive amounts of sulfur into the air, which causes the rain to be damagingly ___________. :(