1.4, 1.5, 1.7 Hydrogen, Carbon, and Nitrogen Cycles

Nitrogen Cycle

The movement of nitrogen between reservoirs

Nitrogen Fixation

A process by which some organisms can convert Nitrogen gas molecules directly into ammonia (NH4+)

Nitrification

The conversion of ammonia (NH4+) into nitrite (NO2-) and then into nitrate (NO3-)

Assimilation

The process by which organisms incorporate elements into their tissues

Ammonification

The process by which decomposers break down the organic Nitrogen found in dead bodies and waste products and convert it into inorganic ammonium (NH4+)

Dentrification

The conversation of Nitrate (NO3-) in a series of steps into the gases Nitrous Oxide (N2O), and eventually, Nitrogen gas (N2) which is emitted into the atmosphere.

Leaching

The transportation of dissolved molecules through the soil via groundwater.

NH4+

Ammonia

NO3-

Nitrate

NO2-

Nitrite

N2

Nitrogen gas

N2O

Nitrous Oxide

Limiting Nutrient

A nutrient required for the growth of an organism but available in a lower quantity than other nutrients.

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Abiotic Fixation

lightning, wildfires, fossil fuel combustion, fertilizer production converts gaseous Nitrogen to Ammonia

Haber-Bosch Process

Industrial (man-made) production of fertilizers by combining nitrogen and hydrogen to synthesize ammonia

Eutrophication

A process by which nutrients, particularly phosphorus and nitrogen, become highly concentrated in a body of water, leading to increased growth of organisms such as algae or cyanobacteria.

Carbon Reservoirs

Relatively stable, short-term stores of carbon on earth. \n \n Ex: fossil fuels, soils and sediments, plant and animal biomass, and the atmosphere

Carbon Sinks

Relatively long-term stores that can take in more carbon dioxide than they produce \n \n Ex: Ocean, soils, sedimentary rock (can be either reservoirs or sinks, depending on their depth & time)

Photosynthesis

Plants use the sun's energy to convert water and carbon dioxide from the atmosphere into sugars and oxygen. Removes CO2 from atmosphere.

Cellular Respiration

Process that releases energy by breaking down glucose and releasing CO2 into atmosphere

Decomposition

A chemical process done by soil bacteria that breaks down organic matter and stores carbon in the soil and releases it into the atmosphere as CO2 and methane (CH4)

Carbon Sequestration (storage)

The act of removing carbon from the atmosphere and storing it. Plants sequester, or store carbon from the atmosphere.

Direct Exchange

Movement of carbon dioxide gas directly between the ocean and atmosphere. \n Happens at a relatively stable rate, although excess atmospheric carbon will increase the level of CO2 in the ocean

Sedimentation

The process of soil particles and decaying organic matter building up in layers on the ground or at the bottom of the ocean. \n Over time, pressure from water or rock layers above compresses sediments into sedimentary rock (limestone) or FFs

Burial/Compaction

The formation of sedimentary rock like limestone, or fossil fuels, as layers of sediments are compressed under the ocean or overlying rock layers.

Extraction

Removal of fossil fuels (coal, oil, natural gas) from the ground, usually by mining or drilling. \n A very rapid process compared to the sedimentation and burial required to form fossil fuel

Combustion of Fossil Fuels

Burning of fossil fuels (primarily in cars and power plants) to release energy \n Releases carbon dioxide into the atmosphere very rapidly, acting as a carbon source

Natural Greenhouse Effect

Heat energy from the sun is retained (kept) in Earth's atmosphere by natural amounts of carbon dioxide, methane, water vapor, and other gases that absorb this reradiated infrared heat energy.

Watershed

The area where all water runoff drains into a single body of water

Runoff

water that flows over the ground surface rather than soaking into the ground

Infiltration

The process by which water on the ground surface enters the soil and/or rock.

Positive Feedback Loop

Feedback loop that causes a system to change further in the same direction.

Negative Feedback Loop

Causes a system to change in the opposite direction from which it is moving.

Positive Feedback Example

Increase in warming causes more evaporation which puts a strong greenhouse gas in the atmosphere (H2O). This causes even more warming.

Negative Feedback Example

Increase in warming causes more evaporation with more and denser clouds that can reflect the sun's energy back out into space. This can have a slight cooling effect on the climate.

Urban development projects like building roads, sidewalks, parking lots (impact on water cycle)

Human activities that increase impermeable surfaces and increase stormwater runoff with a decrease in infiltration into the ground. This creates a stormwater management problem with an increase in flooding.

Transpiration

Evaporation of water from the leaves of a plant

% of Earth is liquid and solid freshwater (ice caps, surface water, groundwater)

2\.5%

Current amount of CO2 in the atmosphere

418 ppm (or 0.04%)

Burning fossil fuels, burning biomass, cutting down trees/plants, farming.

Human activities that increase carbon dioxide (CO2) in the air.

Industrial Revolution

A period of rapid growth in the use of machines in manufacturing and production (and burning fossil fuels) that began in the mid-1700s or early 1800s.

Human-enhanced greenhouse effect

Heat energy from the sun is retained (kept) in Earth's atmosphere by EXTRA amounts of carbon dioxide, methane, and other gases that humans are putting into the air.

CO2 (carbon dioxide)

Greenhouse gas that comes from burning biomass and fossil fuels (coal, oil, natural gas)

Carbon source

Something that puts more carbon into the atmosphere than it takes out (ex: deforestation; burning fossil fuels like coal, oil, natural gas; volcanic eruption)

CH4 (Methane)

Greenhouse gas that comes from cows, landfills, and melting, decomposing permafrost