Environmental Science Midterm Study Guide: Units 1 to 4

Vocabulary-style flashcards covering the key terms, principles, and topics for Units 1 to 4 of the Environmental Science midterm study guide.

Scientific Method

A standardized, step-by-step method of research involving observation, hypothesis formulation, experimentation, data collection, and conclusion drawing.

Descriptive Science vs. Hypothesis-Based Science

Descriptive science aims to observe, explore, and discover nature through qualitative or observational data, whereas hypothesis-based science begins with a specific question or problem and an overarching testable explanation.

Basic Science vs. Applied Science

Basic science seeks to expand fundamental knowledge regardless of short-term practical application, while applied science uses scientific knowledge to solve practical, real-world problems.

Inductive Reasoning vs. Deductive Reasoning

Inductive reasoning uses specific observations to construct broad, generalized conclusions, whereas deductive reasoning starts with a general principle or hypothesis and predicts specific results.

Control Variable vs. Experimental Variable

A control variable is a part of an experiment that is kept constant to prevent outside influences, whereas an experimental variable (independent variable) is manipulated or tested by the researcher.

Frontier Ethic

An anthropocentric worldview that assumes Earth has an unlimited supply of resources and that humans are separate from nature, viewing nature as something to conquer and exploit.

Sustainability Ethic

An environmental philosophy asserting that humans must use resources in a way that meets current needs without compromising the ability of future generations to meet their own needs.

Land Ethic

A philosophy popularized by Aldo Leopold that expands the boundaries of community to include soils, waters, plants, and animals, treating humans as citizens of the natural community rather than conquerors.

Fishbone Diagram

A structured cause-and-effect visualization tool used to identify, categorize, and display the potential root causes of a specific environmental or industrial problem.

Ecological Footprint

A measure of the total area of biologically productive land and water required to produce all the resources consumed and absorb all the waste generated by an individual or population.

Environment vs. Habitat

An environment encompasses the broad sum of all living (biotic) and non-living (abiotic) surroundings influencing an organism, whereas a habitat refers specifically to the physical place or type of site where an organism naturally lives and survives.

Food Chain

A linear pathway that traces feeding relationships and the transfer of energy from primary producers up through successive trophic levels of consumers.

Biomagnification

The increasing concentration of persistent, fat-soluble toxic substances (such as heavy metals or pesticides) in the tissues of organisms at each successively higher trophic level in a food web.

Biogeochemical Cycles

Natural pathway cycles (including the water, carbon, and nitrogen cycles) through which essential chemical elements move between biotic living matter and abiotic environmental compartments.

Chaparral

A temperate coastal biome characterized by mild, wet winters, hot and dry summers, and dense thickets of evergreen, drought- and fire-adapted shrubs.

Aphotic Zone

The deep portion of an aquatic body or ocean where sunlight does not penetrate sufficiently for photosynthesis to occur.

Carrying Capacity

The maximum population size of a biological species that a particular environment can sustain indefinitely, given the food, habitat, water, and other necessities available.

Survivorship Curve

A graph plotting the number or proportion of individuals surviving at each age for a given species, typically classified into Type I, Type II, and Type III curves.

K-selected vs. r-selected Species

K-selected species are adapted to stable environments near carrying capacity and produce few offspring with high parental investment; r-selected species adapt to fluctuating environments and maximize growth by producing numerous offspring with little to no parental care.

Competitive Exclusion Principle

An ecological principle stating that two species competing for the exact same limiting resources cannot coexist at constant population levels if their ecological niches are identical.

Mimicry

An adaptation where one organism evolves to visually, chemically, or behaviorally resemble another organism or object to gain a survival advantage, such as avoiding predation.

Symbiotic Relationships (Mutualism, Parasitism, Commensalism)

Inter-species interactions where mutualism benefits both species, parasitism benefits one species at the expense of the host, and commensalism benefits one species while leaving the other unaffected.

Biodiversity

The variety of all life forms within a given habitat, ecosystem, or the planet, encompassing genetic diversity, species diversity, and ecosystem diversity.

Urban Sprawl

The low-density, automobile-dependent outward expansion of metropolitan areas into surrounding rural or undeveloped lands, leading to increased land consumption and habitat fragmentation.

Highway Revenue Act and Highway Trust Fund

Federal legislation establishing dedicated funding via motor fuel excise taxes to build and expand the interstate highway system, historically incentivizing vehicular transit and suburban development.

Urban Blight

The physical, economic, and social degradation of inner-city areas resulting from population decline, suburban migration, disinvestment, and abandoned infrastructure.

LEED

Leadership in Energy and Environmental Design; a globally recognized green building certification system evaluating energy efficiency, water conservation, material sustainability, and indoor air quality.

Tributary

A stream or smaller river that flows into a larger stream, main stem river, or lake rather than directly into an ocean.

River Discharge

The volume of water moving through a specific cross-section of a river channel per unit of time, typically expressed in cubic meters or cubic feet per second.

Drainage Basin / Watershed

An entire land area that channels rainfall, snowmelt, and tributaries down into a common body of water, such as a river, bay, lake, or ocean.

Water Stress

A condition occurring when the demand for clean, usable water exceeds the available supply over a given time period or when poor water quality restricts its safe use.

Nutrient Overload

The excessive accumulation of nutrients, specifically nitrogen and phosphorus, in water bodies, which accelerates algal blooms and leads to oxygen depletion (hypoxia).

Deepwater Horizon and Exxon Valdez Oil Spills

Two major marine environmental disasters: the $1989$ Exxon Valdez tanker spill in Prince William Sound, Alaska, and the $2010$ Deepwater Horizon offshore drilling rig blowout in the Gulf of Mexico.

Hydrologic Cycle

The continuous biogeochemical movement of water on, above, and below the surface of the Earth through evaporation, transpiration, condensation, precipitation, and runoff.