9 Flashcards
Disturbance?
An event that removes many species and individuals from a community.
Succession?
Colonization or growth of species following a disturbance.
Secondary succession?
Recovery that follows a severe disturbance.
Primary succession?
Colonization of a new habitat.
Successional pathway?
Specific sequence of species that appears over time.
The steps of succession?
Old field (disturbance removed most individuals and weedy species grow) -> Pioneering species (weedy species are replaced by longer-lived herbaceous species and grasses) -> Early successional community (short-lived and fast reproducing individuals) -> Mid-successional community (short-lived individuals mature, long lived trees begin to invade) -> Late-successional community (long-lived tree species mature) -> Climax community (full of K-Selected species)
Above ground biomass (AGB)?
Standing dry mass of live or dead matter from tree or shrub life forms expressed as a mass per unit area.
Biogeoclimatic zones?
What happens if normal fire is not present in a site? (3•)
•Increased pathogens
•increased species diversity
•Increased fire risk due to more fuel
Decomposers?
Secret enzymes into the environment to do the digestion for them to obtain various amino acids and carbohydrates.
Detroitivores?
Digestion that occurs inside of them by eating dead biomass.
Movement of nitrogen in the form of?
Amino acids
Movement of carbon in the form of?
Carbohydrates.
Efficiency of energy transfer?
20% -> 15% -> 10%
Why does less energy get transferred to higher trophic levels?
•Heat generated to keep body temp high (endotherm)
•More energy needed for capturing and finding prey
•Loss of biomass to the decomposer food web because some components are non digestible
•Energy is lost for organisms that undergo metabolism.
How much biomass is used after being consumed?
Most of the biomass is lost after being consumed.
Who takes advantage of the biomass that cannot be consumed by organisms?
Decomposers.
What does nitrogen enter Primary producers as?
NH4+ (ammonium) & NO3- (nitrate)
Nitrogen fixation?
Converting N2 into NH4+
What relationship does nitrogen fixing bacteria form?
Mutualistic relationships with the roots of the plants.
What makes a good biofuel?
•Providing a net energy gain OVER energy used to produce biofuel.
Top down control of productivity?
•When predators control the n of herbivores. •Such reduction can increase growth of primary production
What happens to CO2 in dead biomass if oxygen is lacking?
Decomposition cannot occur and an accumulation of CO2 solidity (heat and pressure from geologic processes). The soild is coal.
Which rate of CO2 release was lower: Volcanoes or humans?
Volcanoes
Consequences of a heating planet RAPIDLY?( 3•)
•Shift in precipitation patterns
•Change in ocean pH
•Altered ecosystems over the planet
Upwelling?
When nearshore ocean currents bring nutrients from the deep ocean to the surface.
Nutrients?
Essential elements such as carbon and nitrogen.
