Ecosystems 2 - Energy Flow & Matter Cycles Flashcards
Energy in Trophic Levels
roughly 90% of energy is lost between each level transfer, which limits the length of food chains in a food web
Energy is used in organisms for
- maintenance of the organism
- growth and reproduction
- lost as heat or excreted waste
Implications of Energy Trophic Level Loss
- Pop. size of top predators remain small while the pop size and biomass of producers needs to be huge
Biomass
combined mass of all organisms of that species/group in the ecosystem
Biomagnification/Bioaccumulation
the concentration of toxins in an organism as a result of ingesting other plants/animals
- consumers accumulate higher toxin concentrations with each trophic position
ELEMENTAL CYCLES
- matter is NOT lost that way that energy can leave the system as heat
- matter is retained in some form in the ecosystem
Compartments
where matter is stored
Flux
movement of matter between compartments
CARBON CYCLE
- Carbon is stored in rock, plants, the ocean
- Carbon can flux due to photosynthesis, respiration, decomposition, and burning
- Carbon cycles quickly through individual organisms, but very slowly through the environment
- ROCK IS THE BIGGEST CARBON COMPARTMENT ON EARTH
“Carbon Sink”
term for rock; because the carbon in rock is unavailable for use, buried deep in the Earth
- Tropical forests = missing “carbon sink”
Carbon Cycle Trends
- increase in CO2 over time
- each year the global atmospheric carbon cycles with a steady pattern that represents the global terrestrial photosynthesis
- CO2 rises in the fall-winter, falls in the summer-spring
Nitrogen Cycle
- cycles between reservoirs
- makes up 78% of the atmosphere as gas, but is not usable by most living things
- cycles via nitrogen fixation, ammonification, nitrification, assimilation, decomposition, denitrification
