Chapter 53 Flashcards
what are the primary producer
autotrophs- can synthesize own food from inorganic sources
what do primary producers do to energy
transform energy into chemical energy
how do primary producers use chemical energy
- cellular respiration
- growth and reprodcution
why is net primary productivity important
it is the amount of energy available via primary producers to other organisms
how does energy flow
when one organism eats another
how is chemical energy lost
as heat, but nutrients continue to cycle
how can you tell if an organism is in the same trophic level
if they obtained energy from the same type of source
what does a food chain focus on
on one possible pathway of energy flow among trophic levels
what pattern is followed in ecosystems pertaining to biomass
total biomass produced each year declines from lower trophic levels up to higher levels
what does productivity measure
- rate
- biomass produced by growth and reproduction
what does efficiency measure
fraction of biomass transferred from one trophic level to the next
the efficiency of biomass transfer from one trophic level to the next is…
10%
what happens to the biomass that is not transferred
released as carbon dioxide and wastes
why are large mammals more efficient at producing biomass
smaller surface-area-to volume ratio and lose less heat
is biomass production more efficient in ectotherms or endotherms
ectotherms because they devote less energy to cellular respiration
biomagnification
increase in concentration of heavy molecules as they are passed up a food chain
when is biomagnification of pollutants higher
the more trophic levels there are
where is productivity higher, land or sea
land because there is more light available for photosynthesis
where on land is productivity the highest and lowest
highest: wet tropics
lowest: deserts
where in marine environments is productivity the highest
coastlines
biogeochemical cycle
path element takes as it moves from abiotic systems through producers, consumers, and decomposers
what is in soil organic matter
mixture of partially and completely decomposed detritus
what does decomposition convert
organic matter to an inorganic form
what three things influence decomposition rate
- abiotic conditions
- the quality of the detritus as nutrient source
- abundance and diversity of detritovores present
if nutrients are lost, where are they transported to
from one ecosystem to another
what are four major mechanisms to replace nutrients
- ions released when rocks weather
- blow in soil particles or arrive in streams
- carbon added
- nitrogen added
global water cycle
movement of water among abiotic and biotic reservoirs in terrestrial and aquatic ecosystems
where is there net gain of water
on land
groundwater
water that is underground
process of the water cycle
- begin with evaporation of water out of ocean
- precipitation of water back into ocean
- net movement of water vapor by wind
- completed by water that moves from land back to ocean
where is most groundwater stored
aquifers; layers of rock, sand, or gravel saturated with water
when are aquifers closed and open?
closed/contained: rocks that don’t allow liquid to flow overlie them
open/uncontained: can be recharged by water percolating down from surface
water table
upper limit of underground layer of soil that is saturated with stored water
global nitrogen cycle
movement of nitrogen among biotic and abiotic reservoirs in terrestrial and aquatic ecosystems
- nitrogen fixation
- denitrification
- decay
what is eutrophication
overfertilization
what are the global biogeochemical cycles
- water cycle
- nitrogen cycle
- phosphorus cycle
- carbon cycle
what is the difference between global warming and global climate change
global warming refers to increase in average temp, while global climate change refers to the sum of all changes in local temp and precipitation
what are the causes to global climate change
- greenhouse effect
greenhouse effect
selective energy absorption by greenhouse gases in atmosphere that causes a warming effect
how does climate change effect the water cycle
- changes where, when, and how much water falls as precipitation occurs
- changes how quickly water evaporates
what does reduced soil moisture increase
risk of fires
what is positive feedback in climate change
changes due to global warming result in further acceleration of warming
what i negative feedback in climate change
changes due to global warming result in increased uptake of CO2 and other greenhouse gases, so global warming should be reduced
what are the biological effect of climate change
- geographic range shifts
- phenology shifts: timing of biological events
- evolutionary adaptation
- extinction
- ocean acidification & deoxygenation
