Ch. 40-43 Ecology: Key Concepts (Populations, Communities, Ecosystems & Energy, Biodiversity & Conservation)

Vocabulary flashcards covering key terms from ecological concepts in Populations, Communities, Ecosystems & Energy, and Biodiversity & Conservation.

Abiotic factors

Nonliving environmental factors such as temperature, water, sunlight, and soil.

Biotic factors

Living environmental factors such as competition, predation, and symbiosis.

Survivorship Type I

High survival early/mid-life with higher mortality later (e.g., humans, elephants).

Survivorship Type II

Constant death rate across the lifespan (e.g., birds, squirrels).

Survivorship Type III

High early mortality with long-lived survivors (e.g., many fishes and plants).

Exponential growth

Population growth with unlimited resources, producing a J-shaped curve.

Logistic growth

Growth that slows as population nears carrying capacity, producing a S-shaped curve.

r-selected species

Many offspring with little parental care (e.g., weeds, many insects).

K-selected species

Few offspring with high parental care (e.g., humans, whales).

Carrying capacity (K)

Maximum population size that the environment can sustain indefinitely.

Density-dependent limits

Limits that increase with population density (e.g., disease, predation, competition).

Density-independent limits

Limits that affect populations regardless of density (e.g., weather, natural disasters).

Exponential growth equation

dN/dt = rN (growth rate proportional to N).

Logistic growth equation

dN/dt = rN (K − N)/K (growth slows as N approaches K).

Interspecific interactions

Interactions between different species.

Competition

/-/- interactions over shared resources, harming both species.

Predation

+/− interaction where one species benefits (predator) and the other is harmed (prey).

Herbivory

+/− interaction where herbivore eats plant (plant harmed).

Parasitism

+/− interaction where parasite benefits at the host's expense.

Commensalism

+/0 interaction where one species benefits and the other is unaffected.

Mutualism

+/+ interaction where both species benefit.

Ecological niche

An organism's role in its environment; includes fundamental vs. realized niches.

Fundamental niche

The full range of abiotic and biotic conditions under which a species could survive and reproduce.

Realized niche

The portion of the fundamental niche actually occupied due to interactions like competition.

Keystone species

A species whose impact on its environment is disproportionately large (e.g., sea otters, starfish).

Foundation species

Species that shape and create habitat structure (e.g., coral reefs, large trees).

Primary succession

Succession starting from bare rock: lichens → soil → plants.

Secondary succession

Succession following disturbance with soil still intact (fires, storms).

Bottom-up control

Nutrients drive the ecosystem from producers to consumers.

Top-down control

Predators regulate lower trophic levels, causing trophic cascades.

Energy flow

Energy moves through an ecosystem in one direction; matter cycles.

Laws of thermodynamics (concepts)

1) Energy cannot be created or destroyed; 2) Energy transfers are inefficient, with heat loss.

Photosynthesis

Process that stores energy in chemical bonds (produces glucose).

Cellular respiration

Process that releases energy from glucose for cell use.

Gross Primary Production (GPP)

Total energy captured by photosynthesis in an ecosystem.

Net Primary Production (NPP)

GPP minus plant respiration; energy available to consumers.

Trophic levels

Producers → primary consumers → secondary → tertiary consumers.

Energy pyramid

Approximately 10% of energy is transferred to each successive trophic level.

Nutrient cycles

Cyclic movement of nutrients (water, nitrogen, carbon, phosphorus) through ecosystems.

Eutrophication

Nutrient overload causing algal blooms and oxygen depletion.

Biodiversity

Genetic, species, and ecosystem diversity within a region.

Ecosystem services

Benefits provided by ecosystems (pollination, water purification, food, medicine).

Pollination

Ecosystem service enabling plant reproduction through pollinators.

Water purification

Ecosystem service that cleans and filters water.

Food (as an ecosystem service)

Provisioning of edible resources from ecosystems.

Medicine (as an ecosystem service)

Pharmaceutical compounds derived from natural ecosystems.