Basic concepts of Ecology Flashcards
What is a species?
A population or populations of organisms capable of breeding naturally among themselves and that produce young that are reproductively viable.
What is a population?
All of the organisms of the same species found within a specific geographic region.
What is the number or terrestrial species?
Terrestrial species account for a million described species… mostly arthropods.
What leads to greater species diversity?
Significantly greater diversity in terms of habitat conditions (elevation, rainfall, slope aspect and steepness, soil conditions and lake and stream conditions) leads to greater species diversity.
How can we protect habitat?
Refuges. Parks. Reserves.
What is the food chain?
Energy stored by plants that moves through the ecosystem in a series of steps of eating and being eaten.
What are trophic levels?
The grouping of species into categories based on common source of food.
What is the 1st trophic level?
Primary producers Plants! (phytoplankton in marine ecosystem).
What is the 2nd trophic level?
Primary consumers Herbivores (essential for higher trophic levels!).
What is the 3rd trophic level?
Secondary consumers Carnivores (first level carnivores).
What is the 4th trophic level?
Tertiary consumers Carnivores (second level carnivores).
What is the 5th trophic level?
Quaternary consumers Carnivores (third level carnivores).
What is the 6th trophic level?
Decomposers Feed on detritus All consumers are decomposers in some way (i.e. feces) Critically important! Bacteria (other microbes) primary decomposers in the ocean.
What is an ecological pyramid?
Indicates the amount of energy flow at each trophic level.
What are food webs?
Food webs- are numerous food chains that link together to form a web with all links leading from producers through an array of primary and secondary consumers.
What are trophic cascades?
Occurs when predators in a food web suppress the abundance of their prey, thereby releasing the next lower trophic level from predation this can occur also when predators are absent from a food web and their prey spike in population.
What is bioaccumulation?
The increase in concentration of a pollutant from the environment to the first organism in the food chain
What is biomagnification?
The increase in the pollutant from one link in the food chain to another.
What is the difference between ecology and environmentalism?
Ecology is a scientific study of the relationships within nature. Environmentalism is a social and political movement that assigns value to aspects of these relationships
What is biocenosis?
A term describing only the biotic or living aspects of an ecosystem.
What are the layers of soil?
Top - organic layer (undecomposed/partially decomposed plant material Topsoil - mineral soil with lots of organic matter Subsoil - clay, salts, larger rock layer Bottom - Unconsolidated materials from parent source
What is the difference between ectothermy and endothermy?
Ectotherms have an internal temperature reliant on the outside environment, whereas endotherms produce their own internal temperature but with more metabolic energy.
What are other names for ectotherms and endotherms?
Ectotherm - poikilotherm Endotherm - homeotherm
What are some ways ectotherms regulate temperature?
Avoidance - hide out during times when too hot or cold Changing orientation - reduces amount of the surface exposed to the sun Large size - conserves metabolic heat by decreasing surface area per volume unit
What are the different levels of organization?
Organism, population/deme, metapopulation, community, ecosystem, biosphere
What is population density?
The number of individuals per unit space
What is ecological density?
The number of individuals per habitable space
What is dispersal?
The movement of an individual from birth to reproduction - the home range
What are the three modes of dispersion?
Clumped - groups of a species Uniform - evenly spaced Random - movement not following a pattern
What factors determine population distribution?
Areas of water, food, shelter, etc., climate conditions, predations, parasites, temperature, topography, etc.
What is a carrying capacity?
The amount of individuals a habitat can support given its resources
What is competition?
The combined demand for a resource that may exceed an immediate supply
What are examples of intraspecific competition?
Exploitation - competitive exclusion Interference - direct confrontation Territoriality - competitive exclusion and direct confrontation Asymmetry - few large individuals and lots of small ones
What are examples of interspecific competition?
Predator - prey Symbiosis - mutualism and neutralism Commensalism Competition Creation of niches Resource partitioning Coevolution
What are the two main types of food chains? What are their steps?
Grazing food chain: primary producers, herbivores, carnivores Detrital food chain: detritus, decomposer herbivores, carnivores
What are the differences between pioneer and climax communities?
Pioneer communities are the first to establish the ecosystem whereas climax communities come in later and is at equilibrium with the environment.
What are biomes?
Any of several major ecosystems characterized by the presence of specific plants and animals, climate, and soil conditions in a specific geographic setting
What is an ectotone?
Boundaries between biomes
What are the 13 types of biomes?
Savannas Temperate Grasslands Chaparral Pinyon-juniper Desert Tundra Boreal Evergreen Temperate Deciduous Tropical Forests Freshwater Systems Saltwater Systems Wetlands Cryptic Systems
What are the six biogeographical realms?
Nearctic (North America) Neotropical (South America, the Caribbean islands) Australians (Australia, several surrounding islands) Oriental (India, Countries Under China, some Islands, Pakistan) Ethiopian (Africa minus small portion northwest, Madagascar) Palearctic (small northwest portion of Africa, Europe, Middle East, Russia, China, Japan, Mongolia)
What is environmental science?
The study of how the world works; examines cause and effect relationships underlying issues and problems that rise from our use of the natural world
What is the difference between conservation and preservation?
Conservation should be used and managed sustainably to provide the greatest benefit to the greatest number of people. Preservation is areas of no human contact.
What are the four main types of terrestrial biomes?
Temperate, tropical, desert, and polar
What is a climatograph?
A graph that shows the pattern of seasonal changes in temperature and precipitation for a particular location.
What are the different types of tropical biomes?
Tropical rain forest, tropical seasonal forest, and tropical savanna
What are the different types of temperate biomes?
Temperate deciduous forest, temperate evergreen forest, chaparral, and temperate grasslands
What are the different types of polar biomes?
Boreal forest and tundra
How do mountains affect climate and weather?
Air temperature drops as altitude increases, rain falls on the mountain as the air climbs, the opposite (leeward) side is dry
How do coastlines affect climate and weather?
Harsh environments suitable for halophytes - transitional area between terrestrial and aquatic biomes
What are the differences between competition, exploitative, and mutualism?
Competition - both species are harmed Exploitative - one species benefits, one is harmed Mutualism - both species benefit