Ch 3 Vocabulary

ecosystem

a particular location on Earth w/interacting biotic + abiotic components

producers (autotrophs)

organisms that use the energy of the sun to produce usable forms of energy

photosynthesis

process in which producers use solar energy to convert carbon dioxide + water into glucose + oxygen

cellular respiration

process in which cells unlock the energy of chemical components (glucose + oxygen are converted back into carbon dioxide, water, + energy)

consumers (heterotrophs)

organisms that are incapable of photosynthesis + must obtain energy by consuming other organisms

primary consumers

organisms that directly feed on producers

secondary consumers

carnivores that eat primary consumers

tertiary consumers

carnivores that eat secondary consumers

trophic levels

successive levels of organisms consuming one another

food chain

sequence of consumption from producers to tertiary consumers

food web

a complex model of how energy + matter move btwn trophic levels

scavengers

organisms that consume dead animals

detritovores

organisms that specialize in breaking down dead tissues + waste products by consuming them

decomposers

fungi + bacteria that convert organic matter into small elements + molecules that can be recycled back into the ecosystem

gross primary productivity (GPP)

total amount of solar energy that producers in an ecosystem capture via photosynthesis over a given amount of time

net primary productivity (NPP)

energy captured by producers in an ecosystem minus the energy producers respire

biomass

total mass of all living matter in a specific area

standing crop

amount of biomass present in an ecosystem at a particular time

ecological efficiancy

the proportion of consumed energy that can be passed from 1 trophic level to another

trophic pyramid

a representation of the distribution of biomass, numbers, or energy among trophic levels

biosphere

region of our planet where life resides (combination of all ecosystems on Earth)

biogeochemcial cycles

movements of matter within + btwn ecosystems

hydrologic cycle

the movement of water through the biosphere

transpiration

the release of water from leaves during photosynthesis

evapotranspirtation

the combined amount of evaporation + transpiration

runoff

water that moves across the land surface + into streams/rivers

macronutrients

6 key elements that organisms need in large amounts (nitrogen, phosphorus, potassium, calcium, magnesium + sulfur)

limiting nutrient

a nutrient required for the growth of an organism but available in a lower quantity than other nutrients

nitrogen fixation (nitrogen cycle)

a process which some organisms can convert nitrogen gas molecules directly into ammonia (puts nitrogen in the base of the food chain)

nitrification (nitrogen cycle)

nitrifying bacteria converts ammonium into nitrite + then into nitrate

leaching

transportation of dissolved molecules through the soil via groundwater

disturbance

an event (caused by physical/chemical/biological agents) resulting in changes in population size or community composition

watershed

all land in a given landscape that drains into a particular stream, river, lake or wetland

resistance

a measure of how much a disturbance can affect flows of energy + matter in an ecosystem

resilience

rate at which an ecosystem returns to its original state after a disturbance

restoration ecology

study + implementation of restoring damaged ecoystems

intermediate disturbance hypothesis

hypothesis that ecosystems experiencing intermediate levels of disturbance are more diverse than those w/high or lower disturbance levels

instrumental value

worth as an instrument or tool that can be used to accomplish a goal

intrinsic value

value independent of any benefit to humans

independent variable

the manipulated/changed variable in an experiment, isn’t changed by other things that you measure

dependent variable

variable being tested/measured in experiment, depends on other variables

assimilation (nitrogen cycle)

producers + consumers absorb nitrogen

ammonification (nitrogen cycle)

nitrogen is returned to the ground by decomposers in the form of ammonia

denitrification (nitrogen cycle)

bacteria converts nitrate into nitrous oxide, released into the atmosphere which makes oxygen poor soil richer

Phosphorus Cycle

1. Weathering of rock (releases phosphate)

2. Excretion from animals (releases phosphate)

3. Runoff (phosphate in the water systems)

4. Precipitation + Conversion (dissolved phosphates become ocean sediments)

5. Geologic Forces (mountains formed by phosphorus rock are pushed up by geological forces)

(NO GASEOUS STAGE)

Nitrogen Cycle

1. Nitrogen Fixation

2. Ammonification

3. Nitrification

4. Assimilation

5. Denitrification

Largest reservoir of phosphorus

rocks + sediments

Largest reservoir of nitrogen

atmosphere

largest reservoir of potassium

Earth’s crust

largest reservoir of sulfur

Earth’s crust (specifically lithosphere)

largest reservoir of oxygen

lithosphere (rocks + minerals)