15_Species diversity in communities_BI370

pragmatic utilitarian conservation ethic

preserving nature for its utility and function for human benefit.

biotic resistance

A measure of how resistant a community is to invasion by invasive species due to species interactions.

Intermediate Disturbance Hypothesis

moderate levels of disturbance promote diversity

complementary hypothesis

Each species equally contributes to ecological functions; linear relationship

redundancy hypothesis

increasing species richness does not increase function beyond a certain point due to overlapping roles; logistic relationship

idiosyncratic hypothesis

impact to a function is species-specific; erratic relationship

mosaic landscapes

from a species perspective, landscapes are incredibly diverse

dumb luck

chance maintains species diversity as long as species are competitively similar and conditions are equal

resource spectrum

may be broad or narrow; influences competition

cultural value of ecosystems

The importance of ecosystems in providing cultural and spiritual benefits to humans.

environmental justice movement

underprivileged people are more likely to be negatively affected by environmental degradation

global environmentalism

acknowledges united global impact of humans

resource partitioning

how a species divides a resource across a spectrum to allow for coexistence

resource ratio hypothesis

species coexist by using different proportions of limiting nutrients

disturbances

can prevent a dominant species from reaching carrying capacity

low levels of disturbance

competitive dominance

high levels of disturbance

excessive mortality and extinction

intermediate levels of disturbance

prevents competitive dominance, but doesn’t cause extinction

positive species interactions

extends the intermediate disturbance curve; facilitation at intermediate levels and tolerance at high levels

diversity in diverse communities

neutral and lottery systems may be strongest

diversity in less diverse communities

species interactions are most important

biocentric preservation

organisms have a fundamental right to exist and pursue their own interests

modern environmental movement

acknowledges impact that modern human society has had on the environment

ecosystem regulation

make environment habitable; air quality, climate, water runoff and quality, erosion, pollution

ecosystem supports

nutrient and water cycling, soil formation, photosynthesis

ecosystem provisions

provides resources; food, biomass, fuel, natural medicines