Earth week 2

Chapter 3 and 4

biomagnification

uptake of contaminants through food chain

bioaccumulation

uptake through water and surroundings

negative feedback loop

output that results from a system moving in one direction acts as inputs that moves the system in the other direction

positive feedback loop

instead of stabilizing it drives it further toward one extreme or another

dynamic equilibrium

system processes move in opposing directions at equivalent rates balancing their effects

resistance

refers to the strength of the systems tendency to remain constant

resilience

is a measure of how readily the system will return to its original state once it has been disturbed

emergent properties

system characteristics not evident in the components alone

gross primary production GPP

conversion of solar energy to the energy of chemical bonds in sugars by autotrophs

Net primary production NPP

energy remaining after respiration, and is used to generate biomass, organic material of which living organisms are formed

ecotones

transitional zones between two ecosystems in which elements of different ecosystems mix

flux

movement of nutrients among pools, which change over time and are influenced by human activity

sinks vs source

sinks accept more nutrients than they release. source release more than they accept

aquifers

underground reservoirs of rock and soil that hold groundwater

how much water is fresh water? how much is available?

2\.8%. 0.62%

how much of our atmosphere is N2

78%

nitrogen fixation

nitrogen fixing bacteria fix nitrogen into ammonia

nitrification

other types of specialized bacteria that convert ammonium ions first into nitrite ions (NO2) then into nitrate ions(NO3)

eutrophication

very productive, blooms of algae

biological evolution

genetic change in populations of organisms across generations

adaptive trait

a trait that promotes reproductive success

maladaptive

trait that reduces success

divergent evolution

closely related species that live in different environments and thus experience different selective pressures tent to diverge in their traits

convergent evolution

unrelated species may have similar traits as a result of adapting to selective pressures from similar environments

biological diversity includes

their diversity of species

their genes

their populations

their habitats

their communities

allopatric speciation

species formation due to physical separation of populations

sympatric species

species form from populations that become reproductively isolated within the same area

endemic species

a species only exists in a certain, specialized area (small population) (susceptible to extinction)

specialists

narrow niches good at what they do susceptible to change

generalists

broad niches that can use a wide array of habitats and resources

limiting factors

water

space

food

predators

disease

biotic potential

the ability of an organism to produce offspring