Chapter 55 Flashcards
Ecosystem Ecology
________________ focuses on the biological community plus the abiotic components in a particular area
ecosystem ecology
ecosystem ecology focuses on three things
- primary production
- energy flow
- nutrient cycling
________________ refers to the chemical energy of food molecules generated by autotrophs, derived from fixation of CO2 during photosynthesis
primary production
primary production is the food source for _______________
all organisms
___________________ is the total amount of carbon fixation by autotrophs in an ecosystem
gross primary production GPP
______________ use approximately half of carbon fixed photosynthesis for cellular respiration, mainintainting their tissues, and organs
autotrophs
the remaining chemical energy not used by autotrophs is ___________________
net primary production
net primary production represents _______________ by an autrotroph
biomass gained
__________________ is left over for the consumption by herbivores and decomposers
net primary production
net primary production NPP is the ______________________________ of an ecosystem
dominant measure of productivity
NPP is controlled by ________________ in terrestrial ecosystems
climate
___________ affects photosynthetic enzymes. at ____________ NPP increases. at _______________ npp may decrease if the photosynthetic enzymes are denatures
temperature
high
very high
water affect photosynthesis vi athe opening and closing of _____________________
stomata
as precipitation increases, npp _____________. with very high precipitation npp ________________ because of cloud cover and less sunlight
increase
decrease
net primary production (NPP) is controlled by _______________________ in aquatic ecosystems
nutrient availibility
_____________ limits NPP in lakes and ponds
phosphorus
net primary production NPP is usually low in ___________________. because the majority of energy is derived from terrestrial organic matter
river and streams
net primary production varries greatly in ______________________.
marine ecosystems
marine ecosystems :
________________________ are very productive NPP
kelp forests and coral reefs
________________ limit NPP in the open ocean
nitrogen and iron
______________ of global NPP is attributed to terrestrial ecosystems. _______________ of global npp is attributed to marine ecosystems
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the average rate of NPP is much greater on Land however ______________________________________
the two are nearly equal due to the large area that oceans cover
the highest rates of NPP on land are found in the ________________________ because they have _________________ temperatures
tropics
high
________________ accounts for high amounts of oceanic NPP in relation to their limited area
coastal zone
the ______________ accounts for the majority of NPP due to its massive volume
open oceans
trophic interactions are _________________ that link organisms in an ecosystem on what they eat and what eats them
feeding relationships
each _________ is based on the number of steps by which it is seperated from the autotrophs in an ecosystem
trophic level
______________ are diagrammatic representations of trophic interactions
food chains
dead organic matter ______________ and wastes _______________ are consumed by ______________ during the process of decomposition
detritus
feces
detrivores (decomposers)
energy flow through an ecosystem
solar energy -> chemical energy within organisms -> heat energy
___________________ is a measure of how much chemical energy in one trophic level makes it to the next trophic level
trophic efficiency
trophic efficiency consists of
- consumption efficiency
- assimilation efficiency
- production efficiency
______________ measure how much energy one trophic level is consumed by the next trophic level
consumption efficiency
comsuption efficiency ranges from _______________
the rest of the energy is not eaten
5-50%
all _________________________ may not be consumed by herbivores due to
the autotrophs chemical and physical defenses
-nutrient poor components like wood compared to nutrient rich like like leaves
autotrophic energy (NPP first trophic level)
_______________________ measure how much energy is incorporated into the next trophic level (by ingestion and absoprtion) to be used for maintenance and defense
assimilation efficiency
assimilation efficiency ranges from
20-80%
the energy that is not assimilated is lost as ___________
waste-feces
assimilation efficiency is _____________ in carnivores than in herbivores. Plant matter contains indigestible material such as cellulose and lignin. whereas animals have the same carbon to nitrogen ratio as carnivores consuming them so they can be assimilated more
greater
________________ measures how much energy from one trophic level goes into the production of new biomass at the next trophic level
production efficiency
production efficiency ranges from ________________________. The rest is lost as _________________ during cellular respiration
1-50%
heat
production efficiency is _____________ in ectotherms than in endotherms because endothernms produce more heat during metabolism
greater
trophic efficiency =
consumption efficiency * assimilation efficiency * production efficiency
trophic efficiency ranges from ________________ averge efficiency
1-20%
10%
the amount of energy available to the organisms at each level in a food chain can be represented as an ______________
energy pyramid
there are rarely more than _______________ because ________ of energy is lost at each trophic level and there is not enough trophic energy to support additional levels
4-5 trophic levels
90%
____________________ diagram the trophic interactions within an ecosystem. They are more realistc than food chains because they are more complex
food webs
_______________________ have a greater influence on energy flow and ecosystem composition than their abundance or biomass might suggest. They tend to be ________________
keystone species
carnivores
_______________ have a large effect on energy flow and ecosystem composition due to their abundance or biomass. Tend to be __________________
dominant species
autotrophs
nutrients are ________________________
recycled within an ecosystem
_____________ is the study of this cycling of nutrients
biogeochemistry
_________________ involves biological, geological, and chemical components
biogeochemistry
nutrients in pools:
flush back and forth to accomplish this cycling
the _________________ are the two largest pools of water
oceans and water vapor
water fluxes between pools by way of _________________
evaporation and condensation
_______________ are the two largest pools of carbon
- atmosphere CO2
- organic carbon in organisms
carbon fluxes between these two pools by
-photosynthesis and cellular respiration
_________________________ are the two largest pools of nitrogen
- atmosphere
- nitrogen in organisms
nitrogen fluxes between these two pools by _______________
nitrogen fixation
_________________ are the two largest pools of phorphorus
- rock/soil
- phosphorus stored in organsism
phosphorus ifluxes between these pools by
decomposition
erosion/ uplifting
