Energy, Trophism, And Productivity Flashcards
What is the primary energy source for life on earth?
Sunlight
What is the difference between open and closed systems?
Energy flows through ecosystems (open system) while nutrients cycle within ecosystems (closed system)
Define autotrophs and heterotrophs
- autotrophs (producers): organism that capture sunlight energy to produce food
- heterotrophs (consumers): organism that get energy by consuming others
Name the types of heterotrophs
Herbivores, carnivores, omnivores, detritivores, decomposers
What is Gross Primary Productivity (GPP)?
The total rate of energy capture by producers from sunlight
What is net primary productivity (nap)
The energy remaining after producers use some for respiration (NPP = GPP - respiration energy)
How efficient is energy transfer between trophic levels?
Approximately 10% of energy is passed to the next trophic level
What is an energy pyramid?
A graphic representation showing energy flow across trophic levels, with less energy available at higher levels
What is ecological efficiency?
The efficiency with which energy is transferred from one trophic level to the next
Can biomass be inverted? If so, in which ecosystems does this occur?
Yes, in aquatic ecosystems where producers like phytoplankton are consumed rapidly
What are trophic cascades?
Changes in one trophic level that influence energy flow and population sizes at multiple levels
What happens to most of the NPP in ecosystems?
It becomes detritus without being consumed by heterotrophs
How much sunlight energy do plants typically absorb?
About 1% of sunlight
What role do decomposes and detritivores play in ecosystems?
They break down dead organic material, recycling nutrients back into the ecosystem
- decomposers (decompose nutrients on a molecular level)
- detritivores (consume material to break it down)
