Flashcards in chapter 21 Deck (59)
moves many elements through ecosystems.
The hydrologic cycle
closely tied to the movement of energy.
The carbon cycle
cycles through ecosystems in many different forms.
cycle that moves between land and water
The phosphorus cycle
nutrients regenerate in the soil in what ecosystems
The movement of water from the oceans to continents is driven by
the Sun’s energy.
the movement of water through ecosystems and atmosphere; includes evaporation, transpiration, and precipitation.
97% of water is found in the oceans where is the reamaining water found
the remaining water is in lakes, streams, rivers, wetlands, underground aquifers, and soil
what happens if evaporation doesnt balance the amount of precipitation
all water would accumulate in one part of the cycle
on a global scale where is precipitation greater than evaporation
in terrestrial ecosystems
where is evaporation greater than precipitation
what happens to excess water that falls on land
it is transported in runoff and groundwater into aquatic systems.
reduces the water that enters the soil and increases runoff.
Creation of impervious surfaces (e.g., roofing, pavement)
roofing, pavement are examples of
decreases evapotranspiration and also increases runoff.
Removing plant biomass
examples of removing plant biomass
cutting down a forest
a way humans use water from the ground before it can be replenished
may increase temperatures and evaporation rates, leading to an intensity of rain and snowstorms.
How might the ocean reduce the effects of fossil fuel combustion on CO2 concentrations in the atmosphere
by absorbing atmospheric CO2
in what habitats is carbon is used for respiration instead of oxygen.
In some O2 -poor habitats (e.g., swamps
has increased to meet energy demands Over the past two centuries
extraction and combustion of fossil fuels (e.g., coal, oil, natural gas)
Combustion of what releases CO2 into the atmosphere?
greenhouse gas that absorbs infrared radiation.
exacerbates the problems of excessive greenhouse gases and global warming
Decomposing peat releases methane gas
How might N-fixing bacteria living in symbiosis w/ a plant affect the types of EVRs in which the plant could live
It would allow the plant to live in areas without much nitrogen (i.e. low nitrogen).
the process of converting atmospheric nitrogen (N2) into forms producers can use, including ammonia (NH3) which is rapidly converted into ammonium (NH4+), and nitrate (NO3–).
occurs in some species of cyanobacteria, free-living species of bacteria (e.g., Azotobacter) and in bacteria that form mutualisms with plants (e.g., Rhizobium).
requires high amounts of energy, which can be obtained by metabolizing organic matter or from mutualistic partners.
occurs when lightning, wildfires, or combustion of fossil fuels provide energy to convert N2 into NO3–.
Abiotic nitrogen fixation