Transcript Biogeochemical Cycling In The Ecosystem pp. 371

Warm- up 3/17:
•What is a trophic level?
•How much energy is transferred between trophic
levels?
• Where does the lost energy go?
Biogeochemical Cycling In
The Ecosystem
pp. 371-374
DEFINITIONS
• Ecosystem: an environment where the
living (biotic) and non-living (abiotic)
things affect one another
• Biogeochemical process: circulation of
substances through living organisms and
the environment
WATER CYCLE
• Evaporation: water vapor enters the
atmosphere
• Transpiration: evaporation of water through
the leaves of plants
• Precipitation: water vapor that leaves the
atmosphere
CARBON CYCLE
• Photosynthesis: converting light energy into
organic compounds
CO2 from atmosphere to macromolecules
• Cellular respiration: breaking down organic
compounds to release energy
Carbon from Macromolecules to CO2
into atmosphere
• Combustion: burning of fossil fuels for
energy releases CO2
Carbon from old Macromolecules to CO2
into atmosphere
NITROGEN CYCLE
• nitrogen fixation: bacteria convert nitrogen
gas to usable form (ammonia)
• ammonification: decomposers break down
proteins/nucleic acids to NH3 (ammonia)
• nitrification: bacteria convert NH3 to
nitrates/nitrites (i.e. like fertilizers)
• assimilation: plants take up nitrates/nitrites to
make amino acids
• denitrification: bacteria return nitrogen to
atmosphere
Homework
Friday:
• Biome Week One Due
• Quiz: Friday
Due Monday:
• Read P 371- 374
• P 374 #1-5
ENERGY TRANSFER
Trophic Level: position in a series of
energy transfers
FOOD CHAIN
•
Single
pathway that
traces the
transfer of
energy
Large Carnivore
• 3˚ Consumer (tertiary)
• Killer Whale
Small Carnivore
• 2˚Consumer (secondary)
• Ex: Sea Otter
Herbivore
• 1˚ Consumer (primary)
• Ex: Sea Urchin
Producer
• Ex: Kelp
FOOD WEB
•Interconnected
food chains
•Arrows show
transfer of
ENERGY