Environmental Flashcards Ch. 8

Front 1

SPECIES EQUILIBRIUM MODEL / THEORY OF ISLAND BIOGEOGRAPHY

Back 1

the number of species found on an island is determined by a balance between two factors: the immigration rate (of species new to the island) from other inhabited areas and the extinction rate (of species established on the island). The model predicts that at some point the rats of immigration and extinction will reach an equilibrium point that determines the islands average number of different species (species diversity)

Front 2

NATIVE SPECIES

Back 2

those that normally live and thrive in a particular community

Front 3

NONNATIVE SPECIES / INVASIVE SPECIES / ALIEN SPECIES

Back 3

those that evolved somewhere else and then migrate into or are deliberately or accidentally introduced into a community

Front 4

INDICATOR SPECIES

Back 4

species that serve as early warnings of damage or danger to a community

Front 5

KEYSTONE SPECIES

Back 5

species that play roles affecting many other organsims in an ecosystem

Front 6

INTERSPECIFIC COMPETITION

Back 6

the most common interaction between speices- competition for shared or scarce resources such as space and food

Front 7

RESOURCE PARTITIONING

Back 7

process of dividing up resources in an ecosystem so that species with similar needs (overlapping ecological niches) use the same scarce resources at different times, in different ways, or in different places

Front 8

PREDATION

Back 8

members of one speices feed directly on all of part of a living organims of another specis (the prey)- the predator benefits and the prey is harmed

Front 9

PARASITISM

Back 9

occurs when one species (the parasite) feeds on part of another organism (the host), usually by living on or in the host- the parasite benefits and the host is harmed

Front 10

MUTUALISM

Back 10

two spcies interact in a way that benefits both - ex. pollination mutualism, nutritional mutualism and gut inhabitant mutualism

Front 11

COMMENSALISM

Back 11

a species interaction that benefits one species but has little, if any, effect on the other speices

Front 12

ECOLOGICAL SUCCESSION

Back 12

process in which communities of plant and animal species in a particular area are replaced over time by a series of different and often more complex communities

Front 13

PRIMARY SUCCESSION

Back 13

ecological succession in a bare area that has never been occupied by a community of organisms

Front 14

SECONDARY SUCCESSION

Back 14

ecological succession in an area in which natural vegetation has been removed or destroyed but the soil is not destroyed

Front 15

PIONEER SPECIES

Back 15

first hardy species, often microbes, mosses, and lichens, that begin colonizing a site as the first stage of ecological succession

Front 16

EARLY SUCCESSIONAL PLANT SPECIES

Back 16

plant species found in the early stages of succession that grow close to the ground, can establish large populations quickly under harsh conditions ,and have short lives

Front 17

MIDSUCCESSIONAL PLANT SPECIES

Back 17

grasses and low shrubs that are less hardy than early successional plant species

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LATE SUCCESSIONAL PLANT SPECIES

Back 18

mostly trees that can tolerate shade and form a fairly stable complex forest community

Front 19

DISTURBANCE

Back 19

a change in environmental conditions that disrupts a community or ecosystem

Front 20

INERTIA / PERSISTENCE

Back 20

the ability of a living system to resist being disturbed or altered

Front 21

CONSTANCY

Back 21

the ability of a living system such as a population to keep its numbers within the limits imposed by available resources

Front 22

RESILIENCE

Back 22

the ability of a living system to repair damage after an external disturbance that is not too drastic

Front 23

COMPLEXITY

Back 23

the number of species in a community (species richness) at each trophic level and the number of trophic levels in a community

Front 24

PRECAUTIONARY PRINCIPLE

Back 24

when there is evidence that a human activity can harm our health or bring about changes in environmental conditions that can affect our economies or quality of life, we should take measures to prevent harm even if some of the cause-and-effect relationships have not been fully established scientifically