8.2: Primary Production Flashcards
1
Q
What is primary production?
A
- the amount of light energy that is converted to chemical energy
2
Q
What do primary producers set?
A
- set a “spending limit” for the entire ecosystem’s energy budget
3
Q
What is gross primary production (GPP)?
A
Total primary production in an ecosystem
4
Q
What is net primary production (NPP)?
A
- the GPP minus the energy used by the primary producers for respiration (Ra)
5
Q
What areas have high NPP and why?
A
- areas with lots of vegetation (Amazon, coral reefs)
- productivity will fluctuate
6
Q
What is Ecosystem energy budgets?
A
- The extent of photosynthetic production sets the spending limit for an ecosystem’s energy budget
Note: more photosynthesis, more energy available
7
Q
What is the global energy budget? (2)
A
- the amount of solar radiation reaching the Earth’s surface limits photosynthetic output of ecosystems
- Only a small fraction of solar energy actually strikes photosynthetic organisms, and even less is of a usable wavelength
8
Q
What is Gross and Net Production?
A
- total primary production is known as the ecosystem’s gross primary production (GPP)
- GPP is measured as the conversion of chemical energy from photosynthesis per Unit time
9
Q
What is Net Primary Production (NPP) expressed as? (2)
A
- energy per unit area per unit time (J/m^2yr) or
- Biomass added per unit area per unit time (g/m^2yr)
10
Q
In terms of biomass, what is NPP?
A
- the amount of new biomass added in a given period (growth)
- so like, is there growth in that area?
11
Q
We get energy from the sun. describe where this energy goes.
A
- 99% goes through the plant or bounces off of it
- ex, radio waves, UV rays, (sinapate esters—> think sunscreen) - 1% is divided: 60% for respiration (tree) and 40% to NPP for other life processes to sustain photoautotroph life
