ecosystems and biodiversity

biome

an ecological system that covers a large area

permafrost

a layer of the ground that is “permanently” frozen (below 32 degrees F)

pyramid of energy

a representation of amount of energy present at each trophic level of a food web

biomass

the total mass of living material

predation

interspecific interaction; a member of one species kills and feeds on a member of another species

herbivory

the consumption of plant material by animals

symbiosis

a relationship between two species that live in intimate contact — types are parasitism, commensalism, and mutualism

parasitism

a close relation between two species in which one benefits at the expense of the other but doesn’t necessarily kill it

commensalism

a close relation between two species in which one benefits, and the other is neither helped nor harmed

mutualism

a close relation between two species in which they both benefit

competition

a relationship between two organisms that struggle for the same resource

resource

anything that an organism needs in order to survive or reproduce

interspecific competition

competition between individuals of different species

intraspecific competition

competition between individuals of the same species

niche

a species’ functional role in an ecosystem, all the physical, chemical, and biological conditions in which it lives and reproduces

principle of competitive exclusion

two species will not occupy the same niche, live in the same habitat, and compete for the same resources for very long

resource partitioning

the idea that over evolutionary time, species divide up scarce resources and reduce competition

fitness

the ability of an individual to survive and produce offspring

tolerance limits

the minimums and maximums beyond which a species cannot survive for each environmental factor

critical limiting factor

a single limiting factor which outweighs the rest in determining whether a species is present in an environment

specialist

a species with a narrow niche

generalist

a species with a broad niche

indicator species

a species whose presence, absence, or abundance in a certain location indicates something about the environmental conditions present there

native species

a species that naturally lives in a particular ecosystem

immigrant species/alien species

a species that has migrated or has been introduced by humans to a certain area

dominant species

the most abundant species in an ecosystem, or the one which has the greatest biomass in an ecosystem

keystone species

a species that plays a role in an ecosystem that affects many other organisms

species diversity/species richness

the number of species in a region

genetic diversity

the variety of genes among individuals in a species

ecosystem diversity

the richness and complexity of a biological community

extinction

the process of a species completely dying out, complete when its last member dies

ecological service

a benefit that people receive from an ecosystem

ecotourism

tourism directly created by ecological sites; an important sector of the economy in many countries

existence value

the positive sentiment experienced by people simply knowing that something exists, even if they don’t personally benefit from it

intrinsic value

the idea that biodiversity is inherently valuable for its own sake

poaching

illegal hunting or fishing

bioaccumulation

the buildup of pollutants in an animal

biomagnification

a process by which contaminant concentrations increase in the tissue of species at higher levels in the food chain

synergistic effects

multiple factors interact with one another, resulting in an overall effect that is greater than the sum of individual effects of any of them

threatened species

a species which is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range

endangered species

a species which in imminent danger of extinction throughout all or a significant portion of its range

precautionary principle

an ounce of prevention is worth a pound of cure (benjamin franklin)

biodiversity hotspot

a region with a high level of biodiversity which is prioritized when looking to obtain the maximum possible benefit in protecting biodiversity

protected area

an area of land and/or sea especially dedicated to the protection of biological diversity and of natural and associated cultural resources, managed through legal of other effective means

deforestation

the destruction of forests

slash-and-burn agriculture

trees are cut down, allowed to dry, and burned to make the soil nutrient-rich, and making the land available for crops or cattle

sustainability

the principle of meeting present-day needs without compromising the ability of future generations to meet their needs

maximum sustainable yield

the act of acquiring the maximum amount of a resource (eg. wood) without depleting the resource

ecological pricing

the idea that the costs of the goods we use should take into account their environmental costs

debt-for-nature swap

an agreement between a country and its debtor(s) in which part of the country’s debt is forgiven in exchange for a commitment to protect part of its land

ecological succession

the process of gradual change in the composition and function of a community

primary succession

the community is developing in a site previously unoccupied by living organisms, a barren habitat with very little topsoil

soil formation

biological factors interact with physical and chemical factors to develop the soil

secondary succession

begins in an area where natural vegetation has been disturbed, but soil remains

primary forest/old-growth forest

a forest that has not been disturbed for an extended period of time (200+ years)

secondary forest

a forest that has regrown after some human disturbance, results of secondary succession

tree plantation/tree farm

an area of trees managed by humans, only containing one or very few species that are commercially valuable (monoculture forestry)