envs sci exam 2

ecology

Ernst Haeckel, the study of interactions among organisms and their abiotic environment

Biotic

living environment

species

similar organisms

populations

groups of organisms that live in the same area

community

natural association of all populations that live in that area

ecosystems

community and physical environment

atmosphere

gaseous envelope surrounding earth

hydrosphere

earths water supply (Frozen and liquid)

lithosphere

soil and rocks of earth crust

biosphere

sum of all ecosystems on earth

what does plant growth require

combination of matter and energy

mass

amount of matter in the object

volume

amount of space the object takes up

atoms

made of three parts; protons, neutrons, electrons

protons

positive charge and are in nucleus

neutrons

no charge; in nucleus

electrons

negatively charged; orbit the nucleus

molecules

made of two or more atoms joined together (discovered by Joseph Priestley 1804)

photosynthesis

6CO2 + 6H2O → C6H12O6 + 6O2

ecological pyramids

graphical representation of the sutrcuture of an ecosystem, showing the relationship between organisms at different trophic (feeding) levels

pyramid of numbers

shows the number of organisms at each trophic level

pyramid of biomass

shows the total biomass at each trophic level

pyramid of energy

show the energy content of biomass at each energy level

GPP

NPP + r

NPP

net amount of biomass (plant growth) produced in an ecosystem, after plans use some for their own respiration

biogeochemical cycles

continuous pathway by which essential chemical elements such as water, carbon, nitrogen, and phosphorus move between biotic and abiotic components of earths ecosystem

which cyles cause dead zones?

Nitrogen cycle, phosphorus cycle

Where is most of carbon stored?

Atmosphere, ocean, land biota, soil, rocks and sediments

What is the main way carbon cycle moves

mainly moves from biosphere to atmosphere

Human induced changes on carbon

fossil fuel combustion, deforestation, soil disruption

Result of human induced changes on carbon

ocean acidification, greenhouse effect + climate change

Nitrogen cycle five steps

nitrogen fixation, nitrification, assimilation, ammonification, denitrification

nitrogen fixation

bacteria in the soil and plans convert atmospheric nitrogen gas into ammonium

nitrification

other bacteria convert ammonia into nitrites and then into nitrates which are easily absorbed by plants

assimilation

plants take up nitrates and ammonium from the soil and conver them into organic molecules such as proteins, dna, rna

ammonification

organisms die and decompose bacteria and fungi convert their nitrogen into ammonia

denitrification

bacteria convert nitrates into atmospheric nitrogen gas

Human induced changes on nitrogen cycle

Fritz Haber - synthesized ammonia(saved lives) invented chemical weapons(killed millions) ++ water pollution (dead zones) + acid deposition

Where is phosphorus stored

cycles through lithosphere

How does phosphorus move

weathering of rocks releases phosphates into soil and water

Human induced changes for phosphorus

fertilizers / detergents,, runoff - excess phosphorus goes into rivers / lakes

result of human changes (phosphorus cycle)

eutrophication - excess growth of algae depleting oxygen in the water cycle

Where is sulfur stored

Stored as sulfide minerals; in atmosphere in gases like sulfur dioxide; biosphere

Main way it moves (sulfur)

volcanoe releases h2s and so2 into atmosphere ; weathing rocks; decomposition of dead organic matter

human induced changes (sulfur)

burning fossil fuels ; industrial process & mining release sulfure into air ; fertilizer

Where is carbon stored? (most and least)

rocks hold most, air holds the least

Where is nitrogen stored ?

72% of the air is n2