chap 4

What are examples of abiotic environmental factors?

Water, shade, permafrost, and dissolved nutrients.

What are examples of biotic environmental factors?

Rhizobacteria, competition, disease, and humus.

What is a population?

All the individuals of the same species living in a specific area.

What is an ecosystem?

Living communities interacting with their abiotic environment (e.g., an aquarium or fallen tree).

What is an ecotone?

A transition area between ecosystems that is typically characterized by high biodiversity.

What are the characteristic plants and animals of the Tundra/Muskeg?

Rapid-flowering plants, mosses, lichens; caribou, ptarmigans, lemmings.

What are the characteristic plants and animals of the Taiga (Boreal Forest)?

Evergreen trees with conical shapes and waxy needles; squirrels, deer, pine martens.

What are the key features of the Grasslands biome?

Extreme temperatures, low precipitation, extensive fibrous roots; bison, hawks, grasshoppers.

What are the key features of the Deciduous Forest biome?

Rich undergrowth, broad canopy; black bears, wolves, woodpeckers.

What is the littoral zone in a lake?

The shallow, sunlit, and highly productive shore area.

What are the three thermal layers of a stratified lake?

Epilimnion (warm top layer), thermocline (transition zone), and hypolimnion (cold bottom layer).

How does eutrophication affect deep-water oxygen levels?

Nutrient runoff causes algae growth; decomposing dead algae below the thermocline increases BOD and depletes oxygen.

What is the relationship between water temperature and dissolved oxygen?

An inverse relationship (warmer water holds less dissolved oxygen).

What is biotic potential?

The maximum reproductive capacity determined by birth potential, survival capacity, breeding frequency, and reproductive lifespan.

What is the difference between density-dependent and density-independent factors?

Density-dependent factors are biotic and impact crowded populations; density-independent factors are abiotic and affect populations regardless of density.

What is carrying capacity?

The maximum number of individuals of a species that an ecosystem can sustainably support over time.

What is the limit of tolerance?

The specific abiotic range an organism can survive within; exceeding it causes die-offs regardless of resources