Unit #8: Ecology

population growth is described by...

• study of the growth, abundance, and distribution of populations
• climate, latitude, habitat size and diversity, and elevation
• toxic chemicals produced in plants that discourage would-be herbivores
• In a lake, the well-lit, open surface waters farther from shore.

occurs when limiting factors restrict the size of a population to the carrying capacity of the habitat; forms an S-shaped curve on a graph

• logistic growth
• exponential growth
• pioneer species
• step in a food chain or food web

population

• two species that live together in close contact during a portion or all of their lives
• carnivores/omnivores, heterotrophs that eat secondary consumers
• obtain energy from light or inorganic material
• freshwater

plants absorb from soils, animals eat plants or other animals

• phosphorus cycle - assimilation
• hydrologic cycle - reservoirs
• hydrologic cycle - assimilation
• A carnivore that feeds on the bodies of dead organisms

carrying capacity

• maximum number of individuals of a population that can be sustained by a particular habitat
• consumer other organisms for organic material and/or a source of energy
• introduced species that proliferates and displaces native species because it is a better competitor or because its natural predators or pathogens are absent
• decomposition

large region of the earth whose distribution depends on the amount of precipitation and temperature in an area; characterized by dominant vegetation and animal life

• biotic
• biosphere
• food web
• coral reef

tundra

• expanded, more complete version of a food chain that shows all major plants in the ecosystem, various animals that eat them, and the animals that eat the animals
• characterized by permafrost "frozen desert" gently rolling plains with many lakes, ponds, and bogs insects are abundant large to medium mammals
• large region of the earth whose distribution depends on the amount of precipitation and temperature in an area; characterized by dominant vegetation and animal life
• denitrification

like trees in a forest; occurs because of special attractions or repulsions

• clumped dispersion
• oligotrophic lakes
• carbon cycle - reservoirs
• the shallow zone of soil and water in lakes and ponds where most algae and emergent plants grow

population ecology

• describes the abundance of individuals of each age
• study of the growth, abundance, and distribution of populations
• deep lakes that are nutrient-poor, oxygen-rich, and contain sparse phytoplankton
• A consumer that eats only plants.

measure of fitness - how well an organism survives and reproduces

• reproductive success
• secondary compounds
• random dispersion
• Species that serve as early warnings that a community or ecosystem is being degraded.