Ecological Pyramids. Energy Loss in Ecosystems I Energy flow through an ecosystem is based on the...
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Transcript of Ecological Pyramids. Energy Loss in Ecosystems I Energy flow through an ecosystem is based on the...
Energy Loss in Ecosystems IEnergy Loss in Ecosystems I Energy flow through an ecosystem is Energy flow through an ecosystem is
based on the laws of thermodynamics based on the laws of thermodynamics (physics)(physics)
First Law: Energy cannot be created or destroyed, it can only change forms
Second Law: When energy is being transformed, some of the energy is converted into an unusable form, and cannot be passed on.
Energy Loss in Ecosystems IIEnergy Loss in Ecosystems II
The energy transferred between trophic levels is inefficient.
on average, only 10% is passed from on average, only 10% is passed from organisms in one trophic level to the nextorganisms in one trophic level to the next
90% of the energy is lost in the form of 90% of the energy is lost in the form of Heat, or used to fuel the activities of the Heat, or used to fuel the activities of the organism that ingested itorganism that ingested it
Ecological Pyramids: The Energy Ecological Pyramids: The Energy PyramidPyramid
energy distribution in a energy distribution in a food chain is best food chain is best illustrated using an illustrated using an pyramidpyramid
the base of all energy the base of all energy pyramids is the producer pyramids is the producer level, and should be the level, and should be the largest sectionlargest section
This is followed by the This is followed by the consumer levelsconsumer levels
Energy PyramidsEnergy Pyramids Are based on the total chemical energy that Are based on the total chemical energy that
flows through each levelflows through each level measured in J or kJmeasured in J or kJ in all in all sustainablesustainable ecosystems, the energy ecosystems, the energy
available to every trophic level is less than available to every trophic level is less than the level before it. The pyramid is always the level before it. The pyramid is always upright!upright!
Ideally, each consecutively higher level is Ideally, each consecutively higher level is approximately 90% smaller than the level approximately 90% smaller than the level directly below directly below
Other Pyramids: BiomassOther Pyramids: Biomass biomass = “total biomass = “total dry massdry mass of a given of a given
population of organisms” population of organisms” biomass combines Number of biomass combines Number of
organisms with the size of the organisms with the size of the organismsorganisms
how much of a particular organism is there how much of a particular organism is there in an ecosystem?in an ecosystem?
usuallyusually, less biomass as you go up trophic , less biomass as you go up trophic levelslevels
exceptionsexceptions e.g. ocean ecosystem e.g. ocean ecosystem
Pyramid of NumbersPyramid of Numbers
a PYRAMID OF NUMBERS tells us how a PYRAMID OF NUMBERS tells us how many many individualsindividuals are present in an are present in an ecosystem ecosystem
these can look very different from these can look very different from energy pyramidsenergy pyramids
many exceptions because of the many exceptions because of the physical size of members of the food physical size of members of the food chainchain
The Energy BudgetThe Energy Budget
in in allall food chains or food webs, energy available food chains or food webs, energy available to maintain it inevitably runs out unless the to maintain it inevitably runs out unless the original energy, sunlight is continuously fed into original energy, sunlight is continuously fed into the systemthe system
There is a limit to how much energy is available There is a limit to how much energy is available in plant population, therefore there is limited in plant population, therefore there is limited available energy to all other levels above plantsavailable energy to all other levels above plants
the “the “ENERGYENERGY BUDGETBUDGET” is the amount of ” is the amount of energy changed from sun to plant that everyone energy changed from sun to plant that everyone has to sharehas to share