Life Sciences - Ecosystem Energetics and Nutrient Cycling

Energy

the ability to do work or the process of doing work

Potential Energy

stored energy. For our purposes this will usually be energy stored in complex organic molecules.

Kinetic Energy

energy being used or released. This includes movement of mass, light, heat, solar radiation, and other forms.

The First Law of Thermodynamics

Energy cannot be created nor destroyed. Account for the energy on both sides of the transformation

The Second Law of Thermodynamics

No transformation is 100% efficient. Without the addition of energy, disorder in a system increases.

Photosynthesis

This process involves the absorption of carbon dioxide by plants, which combined with water and sunlight produces glucose and oxygen.

Cellular Respiration

This process converts oxygen and glucose into water, carbon dioxide and energy (ATP - used to power bodily functions)

1st Trophic Level

Source of Energy: producer

Trophic Name: autotroph

Feeding Pattern: green plant

2nd Trophic Level

Source of Energy: primary consumer

Trophic Name: heterotroph

Feeding Pattern: herbivore

3rd Trophic Level

Source of Energy: secondary consumer

Trophic Name: heterotroph

Feeding Pattern: carnivore

4th Trophic Level

Source of Energy: third level consumer

Trophic Name: heterotroph

Feeding Pattern: carnivore

Food Chain

description of the flow of energy through the populations in a community

Food Web

Representation of all possible transfers of energy in a community

Apex Predator

the predator not eaten by others in the food web

Pyramid of Energy/Biomass

necessary consequence of the 2nd Law of Thermodynamics - visual representation of only 10% energy from one trophic level moving to the next.

Pyramid of Size

animals at higher trophic levels tend to be larger than their prey

Pyramid of Numbers

animals at higher trophic levels tend to be fewer than their prey

Gross Primary Productivity (GPP)

mass of carbon fixed through photosynthesis

Net Primary Productivity (NPP)

mass of carbon fixed through photosynthesis minus that emitted by plants during respiration

Inverted Pyramid of Biomass

In certain marine ecosystems, there appears to be less biomass in a snapshot of the lower trophic levels than the higher ones because of the efficiency of phytoplankton(producers) and zooplankton(primary consumers)

Carbon

element found in biological tissues and atmospheric, geological, and fossil fuel reservoirs

Nitrogen

element found biologically in proteins, DNA, RNA, and tissues. It is also found in atmospheric reservoirs and it is a limiting nutrient used in fertilizers

Phosphorus

element found biologically in tissues and ATP/ADP. It is also found in geological reservoirs, and it is the other nutrient used in fertilizers.

Sulfur

element with a similar cycle to other mineral cycles, except that coal combustion produces an atmospheric version of it

Macronutrients

nitrogen (N), phosphorus (P), potassium (K)

Micronutrients

iron (Fe), calcium (Ca), manganese (Mn), magnesium (Mg)

Combustion

the process of burning something (fossil fuels or trees) - responsible for recycling carbon back into the atmosphere as CO2

Fixation

the process of transforming N2 gas (triple bonded) into NH4 and NH3 (ammonium/ammonia) done by nitrogen fixing bacteria (free living or mutualistic), lightning, or industrial fixation (to produce fertilizer)

Nitrification

the process of transforming ammonium/ammonia (NH4/NH3) into nitrites/nitrates (NO2/NO3), which is usable by plants. This is done by nitrifying bacteria.

Assimilation

plants do this by absorbing the NO2/NO3 (nitrites/nitrates) and converting them into proteins, DNA, and RNA, allowing nitrogen to enter the food chain. This can also apply to the mineral cycles because it means “the process by which living organisms take up and convert inorganic mineral nutrients from the environment into organic compounds necessary for their growth and survival.”

Ammonification

the process of transforming the proteins/DNA/RNA created by plant assimilation into ammonium/ammonia (NH3/NH4). This is done by ammonifying bacteria.

Denitrification

the process of transforming nitrites/nitrates (NO2/NO3) into nitrogen gas (N2). This is done by denitrifying bacteria.

Decomposition

the process of breaking down a substance into simpler components through natural or chemical means

Weathering

the process of breaking down rocks, soil, and minerals into smaller pieces through contact with the Earth's atmosphere, water, and living organisms

Erosion

the natural process where wind, water, or ice wears away land and moves it to another location

Lithification

the process by which unconsolidated sediments, like sand, clay, and gravel, are converted into solid rock through compaction and cementation

Sedimentation

the process where solid particles settle out of a liquid, typically due to gravity, leading to the formation of sediment

Geologic Reservoir

natural underground formations, typically porous and permeable rock layers, that can store fluids or gases like water, oil, natural gas, or carbon dioxide

Tectonic Processes

the movements and interactions of Earth's lithospheric plates, driven by heat from the planet's core, which cause landforms to be created, altered, and destroyed

Leaching

when nutrients are dissolved in water and carried away, either in the groundwater or as surface runoff

Eutrophication

the process where a body of water becomes enriched with excess nutrients, like nitrogen and phosphorus, leading to harmful algal blooms and oxygen depletion