Module 1 | 2. Ecosystem: What are they and How do they do work?

Comprehensive vocabulary flashcards covering Earth's life-support systems, ecosystem components, energy flow, biogeochemical cycles, and scientific methods of study based on Environmental Science 15e.

Tropical Rainforests

Ecosystems that cover only $2\%$ of the earth’s surface but can contain up to half of the world’s terrestrial plant and animal species.

Atmosphere

The spherical component of earth's life-support system composed of the troposphere and the stratosphere.

Hydrosphere

All the water at or near the earth’s surface, including ice, liquid water, and water vapor.

Geosphere

The component of the earth's life-support system composed of a hot core, a thick mostly rocky mantle, and a thin outer crust.

Biosphere

The zones of the earth's air, water, and soil where life is found within the other three spheres.

Greenhouse effect

The interaction between gases and radiation in the atmosphere that warms the earth’s lower atmosphere and surface.

Chemical cycling

The principle of sustainability involving the circulation of nutrients through the biosphere.

Ecology

The study of how organisms interact with each other and with their non-living environment.

Biotic

The living components of the environment.

Abiotic

The non-living components of the environment.

Organism

An individual living being.

Population

A group of individuals of the same species living in a particular place.

Community

Populations of different species living in a particular place and potentially interacting with each other.

Ecosystem

A community of different species interacting with one another and with their nonliving environment of matter and energy.

Cell

The fundamental structural and functional unit of life.

Molecule

A chemical combination of two or more atoms of the same or different elements.

Atom

The smallest unit of a chemical element that exhibits its chemical properties.

Trophic level

A feeding level assigned to organisms depending on their source of nutrients.

Producers (autotrophs)

Organisms, such as plants, that use photosynthesis to make their own nutrients.

Consumers (heterotrophs)

Organisms that satisfy nutritional requirements by feeding on other organisms or their remains.

Herbivores

Primary consumers that eat only plants.

Carnivores

Consumers that eat only meat.

Omnivores

Consumers that eat both plants and meat.

Decomposers

Organisms, such as bacteria and fungi, that break down waste and remains to recycle nutrients.

Food chain

A sequence of organisms, each of which serves as a nutritional source for the next.

Food web

A complex network of interconnected food chains.

Pyramid of energy flow

A diagram representing the decrease in usable energy available at each successive trophic level.

Gross Primary Productivity (GPP)

The rate at which an ecosystem’s producers convert energy into biomass.

Net Primary Productivity (NPP)

The rate at which producers use photosynthesis to produce and store chemical energy minus the rate at which they use energy for aerobic respiration.

Biogeochemical cycling

The movement of nutrients and energy through air, water, soils, rocks, and living organisms driven by solar radiation and gravity.

Hydrologic cycle

The natural cycle that collects, purifies, and distributes the earth’s fixed supply of water.

Transpiration

The process where water evaporates from the surface of plants into the atmosphere.

Surface runoff

Precipitation that flows over the land surface into lakes, reservoirs, and oceans.

Aquifers

Underground layers of rock or sediment that store groundwater.

Carbon cycle

The movement of carbon through the biosphere, regulated by photosynthesis and aerobic respiration.

Nitrogen fixation

The process by which bacteria convert atmospheric nitrogen into a usable form for plants.

Nitrification

The process where bacteria in the soil convert ammonia into nitrate ($NO_3^-$).

Denitrification

The process where bacteria convert nitrogen compounds in the soil back into nitrogen gas for release into the atmosphere.

Phosphorus cycle

The biogeochemical cycle that moves nutrients through soils, rocks, water, and plants, but does not include the atmosphere.

Sulfur cycle

The cycle where sulfur moves through the biosphere via sources like volcanoes, sea spray, and the decomposition of organic matter.

Acid rain

Precipitation containing nitrogen dioxide and sulfuric acid, often caused by human-released sulfur dioxide and nitric oxide.

Hydrogen sulfide ($H_2S$)

A poisonous gas released from active volcanoes as part of the sulfur cycle.

Dimethyl sulfide

A bacteria by-product involved in the natural sulfur cycle.

Field research

Direct observations and measurements taken by scientists in natural ecosystems.

Remote sensing

The use of satellite photography or radio transmitters to track and study organisms from a distance.

Mathematical models

Statistical or computer-based simulations used to study issues that cannot be studied in a lab or field.

Baseline ecologic data

Initial information needed to evaluate the status of ecosystems and develop strategies to prevent degradation.

Planetary boundaries

Thresholds that lead to irreversible changes in the earth's systems if passed.

Detritus feeders

Organisms that feed on the remains of dead organisms and waste products.

Aerobic respiration

The process used by producers, consumers, and decomposers to break down organic compounds and release chemical energy.