#19-Production Flashcards
What is GPP?
Gross primary production
- total amount of carbon formed by autotrophs
- depends on the rate of photosynthesis
What is the LAI
Leaf area per unit of ground area
What happens when you have lots of leaf layers?
The more shading you have, the rate of each added leaf layer decreases
What process are the lower leaves going through ?
Respiration instead of photosynthesis
- not a lot of sun
What happens when there are no leaves being produced?
The costs outweigh the benefits
What is NPP
Net primary productivity
Biomass gained by the plant and the energy left over is use for growth
- GPP-respiration
Why is the storage of carbon good?
Because it can allow regrow to of plant is a disaster occurs
How do you measure NPP?
Estimating biomass before and after growing season
What is the concentration of chlorophyll used for?
Proxy die GPP and NPP
What is NDVI?
Normal sized difference vegetation index
Estimates how green the landscape is
- soil has a low LDVI, vegetation has a high one
What is the NEE?
Net ecosystem exchange production
Change in the concentration of CO2 can be measured in closed chambers
More refined estimate of NPP
- NEE= GPP-(AR+HR) measures weather or not the CO2 is going in or out of the system
What is the eddy correlation ?
NEE is estimated by measuring CO2 at various height in a plant canopy
As NPP increases??
It increases with annual temp and as precipitation increases
What controls NPP in terrestrial ecosystems?
Nitrogen
- in dry meadow, N limited NPP
- in wet meadow, N and P limited NPP
Plants from resource pour communities tend to have
Low growth rates
Requires less nutrients
