Slow, variable,
& fast cycles.
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The transport and removal or
deposition of vital atomic elements needed to
understand the dynamic qualities of ecological systems is embodies in a study of nutrient cycles. Biogeochemical
cycles account for the characteristics, robustness and resilience of ecosystems
to withstand stress, rapid change, or population explosions. Justus Liebig
over 150 years ago defined a "law of the Minimum," by which he understood
that the material element, or nutrient, needed in only trace amounts -- but
necessary to the viability of production is the most serious
limiting factor. |
Carbon atoms arranged in a ball. |
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| For
example, plants cannot photosynthesize without magnesium in
their chloroplasts. Magnesium is not needed in large amounts but is a serious
limiting factor and an example of the law of the minimum. This is particularly
true in tropical climates where water and temperature conspire to increase the rate of evaporation and transpiration in plants.. |
Biological means produced by living things. Fuel, food, fiber
and forage material are all produced by bacteria, fungi, plants or animals.
Chemical
refers to those compounds of an elemental character, referring to the
trace matter, or nutrients that a living creature, or creatures sharing and ecosystem need to function
properly.
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Geological |
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| means both the time and the property
of belonging to the earth's processes even in the absence of living things,
elements predate life on earth. These elements are iron, silica,or magnesium
and compounds such as methane and ammonia. |
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Different
conditions or states of matter on Earth:
gases
solids
liquids
H2O
"Water is the driver of life"
said Leonardo da Vinci.
Water is also the principle
mover, together with the
Earth's tectonic forces, of trace elements and nutrients through the air,
onto the land, into rivers, and oceans and into the rocks of the planet. As
the nutrients pass from one state and one place
to another they are made available for living organisms. This availability
is largely, but not always, the work of bacteria.
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Places on Earth
Air (atmospheric component) wind dispersal,
precipitation and temperature transport.
Water (marine and aqueous component) current
dispersal and removal by currents and evaporation.
Land (terrestrial component) evapo-transpiration
through vegetation, animal and bacteria transport.
Underground (subsurface component) animal
and anaerobic bacteria transport.
Rocks (lithic component) tectonic (slow)
and biological (less slow) transport.
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Slow, variable,
and fast cycles are moved by radiation
heating water and carrying these nutrients
throughout ecosystems.
The state of matter in
which nutrients are moved by inorganic forces has an important influence
on the availability of trace elements. Reservoirs or the total mass of these
compounds on earth are characterized by either readily soluble and thus
moving compounds as opposed to mostly insoluble and sluggish compounds.
Slow cycles can also occur due to the number of states of matter that the
compound element moves before it becomes available to bacteria.
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gases are
most readily distributed from place to place.
Any atomic elements and compounds
of hydrogen, oxygen, nitrogen, sulfur and carbon all have a gas phase.
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liquids are
readily moved by gravity from sources to sinks.
The hydrogen and oxygen compound
of water exists in each of these states on earth and the changes occur
in its condition or arrangement of molecules due to changes in temperature.
Normally a s gas at high (evaporation point: 162° F) temperatures,
water will freeze into a solid at 32° F, or will remain liquid in
the middle range of these temperatures, like other elements and compounds.
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solids are
hard to transport from sinks where they accumulate.
Ice is a solid, but so are metals,
minerals and crystals, the heaviest and often most massive of compounds
and elements on earth. At high temperatures, such as in the core of the
Earth, iron, normally a solid exists as a liquid. The viscous magma from
volcanic explosions is an example of a super heated iron, nickel and mercury
compound that is, at surface temperatures, a solid.
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C. Hopkins
Cafe
Nutrients
are those compounds or elements called trace elements, because they are so
scarce and they are needed only in the least amount, for necessary functions
of life in ecological systems to sustain itself and other forms of life.
qualities versus quantities
They come in two quantities based on how
much of the compound is needed for living things to function in a healthy
condition:
1. Major trace elements are: calcium, potassium,
Magnesium, phosphorus, sulfur, carbon, oxygen, sodium and nitrogen
2. Minor trace elements are: copper, cobalt,
manganese, molybdenum, boron, zinc, iodine, and iron.
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Nutrients exist
with several qualities related to the frequency of their availability for living
creatures:
| Fast cycling and readily available: oxygen,
sodium and nitrogen, |
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| Atomic element |
Roles of nitrogen in the land, air, and water. |
animated N, nitrogen cycle |
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Slow cycling and scarcely available: sulfur, calcium, potassium, magnesium, phosphorus, copper, cobalt, manganese,
molybdenum, boron, zinc, iodine, and iron.
 
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These are compounds often needed in the least amount and are examples of the law of the minimum. |
| Variable cycling: carbon. |
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atomic structure |
compound molecule |
the biogeochemical cycle |
| Atoms |
Compounds |
Cycles |
In the temperate rainforests of the Pacific rim carbon moves due to photosynthesis.
A miraculous transformation, or as Oliver Sacks has suggested:
"It is impossible to imagine a world without photosynthesis . . . this most important life process."
More
on nutrients
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