Ecology and Environment - Vocabulary Flashcards

Vocabulary flashcards covering key ecological concepts, processes, and terms from the lecture notes.

Ecology

Scientific study of the interactions of organisms with their environment that determine the distribution and abundance of a species.

Interaction

One of the components of ecology describing how organisms interact with each other and with their environment.

Environment

All external conditions and factors (biotic and abiotic) that affect an organism’s life.

Distribution

Where organisms are found across a space or region.

Abundance

Number or density of individuals of a species in a given area.

Desertification

Process by which soil becomes unproductive, especially in arid to semi-arid regions, due to factors like deforestation, overgrazing, and climate change.

Deforestation

Removal of forest cover leading to soil degradation and erosion.

Overpopulation

Excessive population pressure contributing to land degradation and resource strain.

Overgrazing

Grazing too much or too long with too small an area, destroying vegetation and causing erosion.

Des er tification factors

Key drivers include deforestation, overgrazing, climate change, and unsustainable land practices.

Eutrophication

Nutrient enrichment of a body of water leading to increased biological productivity.

Trophic State Index (TSI)

Classification system to rate water bodies based on algal productivity using chlorophyll-a, total phosphorus, and water clarity.

Chlorophyll-a (Chl-a)

Algal pigment concentration used to estimate phytoplankton biomass.

Phosphorus (P) in water

Total phosphorus; a key nutrient influencing eutrophication and TSI.

Oligotrophic

Low-nutrient, clear-water condition with minimal productivity (TSI typically <30–40).

Mesotrophic

Moderate-nutrient water with intermediate productivity (TSI ~40–50).

Eutrophic

High-nutrient water with high productivity and often poor visibility (TSI ~50–70).

Hypereutrophic

Excessively nutrient-rich water with very high productivity and potential dead zones (TSI ~70–100).

Natural eutrophication

Slow lake aging due to natural nutrient and sediment inputs over centuries.

Anthropogenic eutrophication

Human-caused eutrophication from urban runoff, sewage, fertilizers, and related sources.

Abiotic

Non-living components of the environment.

Chemical abiotic factor

Chemical properties that affect organisms (e.g., N, P, K; salts; pH; soil gas; water; iron–oxidation).

Physical abiotic factor

Non-chemical physical factors (e.g., water movement, temperature, topography, light).

Biotic

Living components of the environment (predators, prey, symbionts, disease agents).

Predators

Organisms that capture and consume other organisms.

Prey

Organisms that are consumed by predators.

Symbionts

Organisms living in close, long-term interaction, often beneficial.

Pathogens (organisms of disease)

Biotic agents that cause disease in other organisms.

Distribution (ecology context)

Geographic range where a species occurs.

Abundance (ecology context)

Population density or total number of individuals in an area.

Rio Grande Leopard Frog

Amphibian with a broad range in southern, western, and central Texas.

Texas Blind Salamander

Endemic salamander found only in Hays County, Texas.

Honey Mesquite

Widespread Texas tree; common in many regions of the state.

Texas Snowbell

Plant found in Uvalde and nearby counties.

Eastern Meadowlark

Bird with broad U.S. distribution; populations declining in many areas.

American Robin

Bird breeding in Canada and northern U.S.; wintering range broad including Florida and Texas border areas.

Ecological Hierarchy

Levels from individual to biosphere: individual, population, community, ecosystem, landscape, biome, biosphere.

Individual

Single organism.

Population

Group of individuals of the same species in a given area.

Community

All populations of different species in a given area.

Ecosystem

Biotic community and its abiotic environment functioning as a system.

Landscape

Area composed of patches of communities and ecosystems.

Biome

Broad regional scale dominated by similar ecosystem types.

Biosphere

Thin global zone where all life exists.

Climate

Long-term average weather patterns for a region.

Electromagnetic radiation

Radiant energy from the sun that travels as waves and particles.

Temperature

Measure of heat in a system; affects climate and biological processes.

Global air movement

Movement of air masses driven by temperature differences and rotation (Hadley, Ferrel, Polar cells).

Microclimates

Small-scale climate differences in a local area.

Weather

Atmospheric conditions at a specific place and time.

Albedo

Fraction of light reflected by a surface (0 to 1).

Photoperiod

Duration of daily light exposure for organisms.

Visible light

Wavelengths ~380–760 nm; energy drives photosynthesis and biological cycles.

Ultraviolet (UV)

Short-wavelength, high-energy light (380–100 nm) that can be damaging; ozone layer protects organisms.

Infrared (IR)

Long-wave radiation associated with heat energy (thermal energy).

Photon

A discrete packet of electromagnetic energy; energy proportional to frequency.

Wavelength

Distance between successive peaks in a wave; determines color in visible light.

Frequency

Number of cycles per second (hertz, Hz) of a wave or photon.

Albedo values (examples)

High albedo: snow/ice (~0.9); low albedo: bare ground/vegetation/water (~0.05).

Intercepted solar radiation

Solar energy reaching Earth's surface varies with latitude and angle of incidence.

Latitude effects on energy

Equator receives more energy per area; poles receive less due to angle and atmosphere.

Equinox

Two yearly points when day and night are approximately equal in length; Sun over the equator.

Solstice

Two yearly points: Summer (sun over Tropic of Cancer) and Winter (sun over Tropic of Capricorn).

Hadley cell

Large-scale atmospheric circulation from the equator to 30°N/S, driving tropical wet/dry patterns.

Ferrel cell

Mid-latitude atmospheric circulation between 30° and 60° N/S.

Polar cell

High-latitude atmospheric circulation from 60° to 90° N/S.

Coriolis force

Apparent deflection of moving objects due to Earth's rotation, causing wind and current patterns.

Relative Humidity (RH)

Amount of moisture in the air relative to how much the air can hold at a given temperature.

Saturation Vapor Pressure (SVP)

Maximum amount of water vapor the air can hold at a given temperature.

Actual Vapor Pressure (AVP)

Actual amount of water vapor present in the air.

Rain shadow / Orographic effect

Moist air rises on the windward side, cools and releases moisture; leeward side is dry as air descends.

Windward vs Leeward

Windward side receives moisture; Leeward side is drier and cooler on average.

Cold water currents

Ocean currents that transport cool water along coastlines, affecting nearby climates.

California Current

Cold ocean current along the western edge of North America.

Humboldt Current

Cold Pacific current off South America influencing arid conditions inland.

Continental vs Coastal climates

Land heats and cools faster than sea; coast moderated by sea, leading to milder temperatures and different precipitation.

Specific heat (water vs land)

Water has high specific heat, absorbing/releases large amounts of heat with small temperature change; land has low specific heat.

Heat sink

Large body of water that absorbs heat with little change in temperature.

Microclimates (repeated term)

Localized climate variations within a small area.

North-facing slope (Northern Hemisphere)

Generally cooler, wetter, lower irradiance due to indirect sun angles.

South-facing slope (Northern Hemisphere)

Generally warmer, drier, higher irradiance due to direct sun angles.

North-facing slope (Southern Hemisphere)

In the Southern Hemisphere, opposite pattern of irradiance compared to the Northern Hemisphere.

Soil Temperature Profile

Soil temperature varies most at the surface and stabilizes with depth; buffers exist against extremes.

Biome

Major regional ecological community characterized by dominant vegetation and climate.

Whittaker (1975)

Ecologist who helped define ecological hierarchy and biomes.