Primary Production Flashcards
What is primary production?
Photosynthesis, using carbon to create food
GPP=?
NPP+R
What happens as CO2 is used for Photosynthesis?
Water becomes more alkaline pH becomes higher
What Reactions make up photosynthesis?
Light and dark reactions
Light reaction
Noncyclic photophosphorulation
Capture light via the sun using chloroplasts filled with chlorophyll
Dark Reaction
Calvin cycle and carbon fixation
Turns CO2 into carbohydrate for plant to consume
Why do plants have multiple pigments?
In order to absorb a greater portion of the light spectrum. These pigments are very efficient at capturing light.
What influences photosynthesis in streams
Light which is varies by season, terrestrial vegetation, particles/solutes, and algal matrix
Photosynthesis irradiance curve
non-linear curve for the intensity of light and production of photosynthesis. Point of maximum photosynthesis, after which light is too intense.
Shade adaptations/photoinhibition
Shade adaptation refers to changes in photosyn. efficiencies ad changes in saturation/photoinhibition parameters
What effect does shade have on PP in stream?
Decreases PP, but also causes Producers to be efficient with sunlight. Whereas high intensity light areas would be better photo inhibitors and more tolerant to intense light
What else controls photosynthesis?
Channel unit dimensions, substrate stability and size, streamflow regime, temperature (metabolism), nutrients
How does PP change with stream order?
Small first order stream have limited PP, increasing PP with increasing stream order. Vegetation and light penetration are defining factors.
Autochthonous
Within; net primary production within stream
Allochthonous
Energy produced OUTSIDE the system
