Lecture 2 Flashcards
Gross Primary Production (GPP)
total amount of carbon fixed per area per unit time
Relation between temperature and the intensity and duration of sunlight
Temperature and the intensity and duration of sunlight are strongly linked, i.e. warmer temperatures are associated with longer growing seasons.
The influence of precipitation and temperature on terrestrial primary production is _________
The influence of precipitation and temperature on terrestrial primary production is interrelated
Heavy precipitation and warm temperatures can support the most productive terrestrial ecosystems (tropical rainforests)
Transpiration
loss of water vapour to the atmosphere by land plants
Evapotranspiration
loss of water vapour to the atmosphere from plants and the soil
Would rates of primary production increase, or decrease when evapotranspiration rates are great?
In general, production increases with evapotranspiration
Evapotranspiration integrates the effect of ______ and _______ on primary production
Evapotranspiration integrates the effect of temperature and moisture on primary production
In summary: warm temperatures and sufficient water (to meet the needs of transpiration) can result in great rates of _________ ________.
In summary: warm temperatures and sufficient water (to meet the needs of transpiration) can result in great rates of primary production.
_____ is then loss of water through the stomata
Transpiration is then loss of water through the stomata
When _____ closed, plants undergo _______ by increased O2 levels by Rubisco, stopping primary production in hot temperatures
When stomata closed, plants undergo photorespiration by increased O2 levels by Rubisco, stopping primary production in hot temperatures
CAM plants open stomata at _____, cycling CO2 into acids to be transferred into the ______ cycle during the day
CAM plants open stomata at night, cycling CO2 into acids to be transferred into the Calvin cycle during the day
C4 plants keep stomata ______ in hot temps
C4 plants keep stomata closed in hot temps
PEP transfers any CO2 into a 4-C compound, and then mediates the Calvin cycle process
High levels of evapotranspiration =
high primary productivity→a result of the rapid movement of water through the plant
Nutrient Levels
Nutrient levels can define the abilities of plants, both inorganic and organic, and must be bioavailable (some nutrients are locked up in inaccessible compounds)
• The rate at which nutrients can be mineralized (made available) can be the limiting factor controlling primary production
