Energy flows Flashcards
Give the 2 types of energy in a food chain
potential (contained within something) and kinetic (movement)
Give the 2 laws of thermodynamics
- Energy is neither created nor destroyed
2. Entropy (loss of potential energy) increases - not all energy is conserved
Define primary productivity
the rate at which biomass is produced by photosynthetic and chemosynthetic autotrophs in the form of organic substances
What is the gross primary production (GPP)?
The total energy assimilation
What is net primary production (NPP)?
the rate of energy storage / the energy available to heterotrophs
What are the units of primary production?
kcal/m2/yr (energy per unit area over time) and g/m2/yr (dry organic matter per area over time)
What is standing crop biomass (SCB) and what is it measured in?
the amount of accumulated organic matter in an area at a given time
What is the equation for calculating net primary production (NPP)?
standing crop biomass (SCB) + death of plants + loss of biomass due to consumption by consumer organisms
Where is terrestrial primary productivity highest and why
in the tropics, as primary production increases with evapotranspiration, which in turn increases with increased precipitation and temperature
Which aquatic environment is likely to have the highest net primary productivity (NPP)?
where waters are shallow and nutrient-rich
Define secondary production
net energy of production (growth of new tissue, production of young) by heterotrophs
What are the 2 major food chains and how do they differ?
grazing food chain (primary producers -> herbivores -> carnivores) and detrital food chain (detritus -> decomposer herbivores -> carnivores)
What 2 measures make up the ingested energy?
assimilated energy and waste energy
what 2 measures make up the assimilated energy
energy for respiration and production
How can the assimilation efficiency be calculated?
assimilated energy / ingested energy
