Nutrient Cycles aka Biogeochemical Cycles matter that organisms
Nutrient Cycles aka Biogeochemical Cycles matter that organisms must have to survive
1. Water Cycle involves: evaporation, condensation, precipitation, infiltration, runoff, percolation, and transpiration * absolute humidity actual amt of water vapor in the air * relative humidity absolute humidity ÷ by the amt of water vapor the air can hold at that temp. X 100 = % high temps = more H 2 O vapor the air can hold
* precipitation will only occur if water vapor has condensed around tiny particles called. . . CONDENSATION NUCLEI can be volcanic ash, dust, smoke, sea salts, particulates from factories & cars How do humans affect the water cycle?
Carbon is a Girl's Best Friend
2. Carbon Cycle - primary component of all organic compounds (carbs, fats, proteins, DNA) - based on CO 2 - includes 2 biological processes. . a. b. Respiration carbon dioxide water glucose oxygen mitochondria
Areas on Earth where large amounts of a nutrient is stored are known as SINKS or RESERVOIRS A major sink for carbon is the oceans. - CO 2 is dissolved in the water. - Much carbon is also found in the form of Ca. CO 3 to build shells and skeletons of sea organisms
How do humans affect the carbon cycle?
3. Nitrogen Cycle All organisms must have nitrogen as it is an essential component of DNA, RNA, and proteins—the building blocks of life. The largest single source of nitrogen on Earth is in the atmosphere. N 2 makes up 78% of our air!
In one of nature’s great ironies… The majority of the air we breathe is N 2, however most living organisms are unable to use nitrogen in that form!
How does N 2 get changed into a form that can be used by most living organisms?
(1) Nitrogen Fixation (4) Denitrification Nitrogen Cycle (3) Nitrification (2) Ammonification
* Nitrogen fixation conversion of N 2 to NH 3 There are two types of “Nitrogen Fixing Bacteria” Symbiotic bacteria live in nodules on the roots of legume plants (peas, soybeans, alfalfa) and provide the plants with ammonia Symbiotic Bacteria (NH 3) in exchange for (“fixes” 70% of N 2) the plant’s carbon and a protected home. Free Living Bacteria
* Ammonification conversion of amino acids from decaying organisms to NH + 4 Bacteria converts organic nitrogen to ammonium Ammonium (NH 4+) can be used directly by some plants Ammonium (NH 4+) may also be stored in the soil
* Nitrification conversion of NH 3 to NO 2 and NO 3 - (occurs in bacteria) Nitrifying bacteria in soil combine ammonia with oxygen Ammonia changes to nitrites Nitrifying bacteria in soil convert nitrites to nitrates Ammonia Nitrites Nitrates (NH 3) (NO 2 -) (NO 3 -) Plants absorb nitrates
* Denitrification conversion of forms of nitrogen back to N 2 by bacteria Nitrogen in atmosphere closes the nitrogen cycle! (NO 3 -)
Other ways that nitrogen returns to the atmosphere… Emissions from industrial combustion and gasoline engines create nitrous oxides gas (N 2 O). Volcano eruptions emit nitrous oxides gas (N 2 O). How do humans affect the nitrogen cycle?
4. Phosphorus Cycle - Found mostly in proteins, lipids and nucleic acids. - Circulates through water, organisms and rock - Very little found in the atmosphere
- major limiting factor in plant growth so it is a main ingredient in fertilizer
5. Sulfur Cycle - In organisms, found mostly in proteins - Most of Earth’s sulfur is stored as SO 4 -2 underground in rocks and minerals in addition to ocean sediments.
How do humans affect the sulfur cycle?
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