Introduction to Ecology and Life on Land Vocabulary

Vocabulary terms and definitions extracted from lecture notes on introductory ecology, scientific method, climate, biomes, soil properties, and aquatic ecosystems.

Ecology

The scientific study of interactions between organisms and their environment.

Ecosystem

All the organisms in a given area as well as the physical environment in which they live.

Biotic Factors

Living components of the ecosystem, including animals, plants, fungi, and microorganisms, which interact and fulfill specific ecological roles.

Abiotic Factors

Non-living components of the ecosystem, such as temperature, wind, soil moisture, soil nutrients, light, precipitation, and climate.

Producer

An organism that produces its own energy without eating other organisms.

Consumer

An organism that obtains its energy by eating other organisms.

Metabolism

Chemical processes that occur within a living organism in order to maintain life.

Biomass

The total mass of organisms in a particular area.

Net Primary Production (NPP)

The amount of energy producers capture by photosynthesis minus their metabolic heat.

Evolution

The change in allele frequencies or genetic characteristics of a population over time.

Adaptation

A characteristic of an organism that improves its ability to survive and reproduce.

Natural Selection

The process in which individuals with certain characteristics tend to survive and reproduce at a higher rate because of those characteristics.

Independent Variable

The variable in an experiment that is directly manipulated by the biologist.

Dependent Variable

The variable in an experiment that may respond to changes in the independent variable.

Standardized Variable

Any variable in an experiment that is intentionally held constant.

Scientific Theory

To scientists, a unifying explanation for a broad range of observations that represents certainty and is supported by a large body of evidence.

Biomes

Major divisions of the terrestrial environment, distinguished by their predominant plants and associated with particular climates.

Saturation Vapor Pressure

The maximum amount of water vapor that air can hold at a given temperature.

Coriolis Effect

The spin of Earth that deflects wind direction.

Rain Shadow

A climate effect created by mountains where air rises, cools, and drops precipitation on the windward side, leaving the leeward side dry.

Urban Heat Island

An urban climate phenomenon where man-made structures absorb heat and air pollution traps thermal radiation, causing cities to produce elevated temperatures.

Albedo

The amount of solar radiation reflected by a surface.

Saturated Soil

A soil condition where water content exceeds available pore space.

Field Capacity

The state when water has filled the soil and it cannot absorb any more.

Permanent Wilting Point

The point of low soil moisture where there is not enough water available and plants start to wilt.

Available Water Capacity

The water level stored in soil available to plants, located between field capacity and wilting point.

Cation Exchange Capacity

The soil process where a nutrient on a negatively charged surface is exchanged for another cation.

Soil Leaching

The movement of dissolved matter from upper soil layers to lower layers.

Permafrost

Subsurface soil layer in high-latitude biomes that remains frozen continuously and does not thaw.

Lotic System

An aquatic ecosystem consisting of moving water, such as rivers and streams.

Lentic System

An aquatic ecosystem consisting of stationary water, such as lakes and ponds.

Watershed

A drainage area that includes connected aquatic and terrestrial ecosystems where all runoff ends up in a shared body of water.

Oligotrophic Lakes

Lakes characterized by nutrient-poor water, low algae and plant growth, and clear conditions.

Eutrophic Lakes

Lakes characterized by high nutrient levels, shallow depths, warmer temperatures, and high plant or algal growth.

Eutrophication

The over-fertilization of a body of water that causes excessive growth of plants and algae.

Estuary

A highly productive aquatic system located where a river meets the ocean.