2.3 flows of energy and matter

Ecological Efficiency

The percentage of energy transferred from one trophic level to the next in an ecosystem.

Solar Radiation

Energy from the sun that enters the Earth's atmosphere.

Reflection

The bouncing back of solar radiation by clouds, aerosols, or the Earth's surface.

Absorption

The process of solar radiation being taken in by clouds, molecules, or dust in the atmosphere.

Chloroplasts

Organelles in plant cells where photosynthesis takes place.

Biomass

The total mass of living organisms in a given area.

Trophic Level

The position of an organism in a food chain or food web.

Ecosystem

A community of living organisms and their physical environment.

Primary Productivity

The rate at which producers (autotrophs) convert solar energy into chemical energy.

Secondary Productivity

The rate at which consumers (heterotrophs) gain energy or biomass through feeding and absorption.

Gross Productivity

The total gain in energy or biomass per unit area per unit time.

Net Productivity

The gain in energy or biomass per unit area per unit time remaining after accounting for respiratory losses.

Respiration

The process by which organisms release energy from organic compounds.

NPP (Net Primary Productivity)

the gain by producers in energy or biomass per unit area per unit time after accounting for respiratory losses.

GPP (Gross Primary Productivity)

the total mass of glucose created by photosynthesis per unit area per unit time in primary producers.

NSP (Net Secondary Productivity)

the gain by consumers in energy or biomass per unit area per unit time after accounting for respiratory losses.

GSP (Gross Secondary Productivity)

the gain in energy or biomass by consumers through absorption per unit area per unit time. (amount of food absorbed by the consumer)

Respiration (R)

The energy lost through cellular processes and released as heat.

NPP = GPP - R

The equation to calculate Net Primary Productivity by subtracting respiration from Gross Primary Productivity.

GPP = NPP + R

The equation to calculate Gross Primary Productivity by adding respiration to Net Primary Productivity.

Respiration

the loss of glucose as it is broken down.

how to calculate NSP

measuring the increase in biomass over a specific amount of time.

ASY (Annual Sustainable Yield )

the annual gain in biomass or energy through growth and recruitment.

MSY (Maximum Sustainable Yield )

the highest rate of harvesting that does not lead to a reduction in the original natural capital.

Nutrient Cycles

Simple diagrams that show stores and transfers of nutrients in ecosystems.

Macronutrients

Nutrients needed in large quantities, including oxygen, carbon, hydrogen, and nitrogen.

Micronutrients

Nutrients needed in small quantities, including magnesium, sulfur, and phosphorus.

Carbon Cycle

The cycling of carbon through ecosystems, involving organic and inorganic storage, transfers, and transformations.

Nitrogen Cycle

The cycling of nitrogen through ecosystems, involving the conversion of nitrogen gas into usable forms by organisms.

Nitrogen Cycle

The process by which nitrogen is converted and recycled in various forms in the environment.

Phosphorus Cycle

The process by which phosphorus is cycled and recycled in the environment.

Organic storage

Storage of nitrogen and phosphorus in living organisms.

Inorganic storages

Storage of nitrogen and phosphorus in soil, fossil fuels, atmosphere, and water bodies.

Transfers

Movement of nitrogen and phosphorus through different organisms and processes.

Transformations

Chemical changes that occur during the nitrogen and phosphorus cycles.

Lightning

A natural process that converts nitrogen in the atmosphere into nitrate.

Nitrogen-fixing bacteria

Bacteria that convert nitrogen gas in the atmosphere into ammonium ions.

Nitrifying bacteria

Bacteria that convert ammonium ions into nitrite and then nitrate.

Denitrifying bacteria

Bacteria that convert nitrates into nitrogen gas.

Decomposers

Organisms that break down organic nitrogen into ammonia.

Assimilation

The process by which plants use nitrates to make amino acids and proteins.

Acid deposition

The deposition of acidic substances in the environment due to human activities.

Albedo

The reflectivity of a surface, which can be reduced by human activities.