Ecology - Chapters 3 and 4

• Primary production = the amount of energy that enters into an ecosystem through photosynthesis.
• Biomass = the total mass of living organisms present in an ecosystem.
• Ecology


  The study of the interactions between organisms and their physical environment
• Components of the biosphere(BBECPO)


  • Biosphere
  • Biome
  • Ecosystem
  • Community
  • Population
  • Organism
• Biotic factors = living factors
• Abiotic factors


  • Non-living factors
  • Atmosphere
  • Hydrosphere
  • Geosphere
• Weather


  Day to day conditions
• Climate


  Long term patterns of precipitation and temperature over many years
• The sun affects


  The climate and biomes that form
• ENSO


  El Nino and La Nina, weather patterns involving the movement of warm surface water in the oceans
• ENSO is irregular and difficult to predict long term
• Symbiosis


  • Parasitism (one benefits, one is harmed)
  • Commensalism (one benefits, one is unchanged)
  • Mutualism (both benefit)
• Energy flow


  • Energy comes from the sun
  • Autotrophs (producers)
  • Heterotrophs (consumers)
  • Carnivores
  • Herbivores
  • Omnivores
  • Scavengers
  • Decomposers
• Trophic levels


  • Autotrophs
  • First order heterotrophs
  • Second order heterotrophs
  • Third, fourth, etc. order heterotrophs
• Processes that cycle matter

  • Biological
  • Geological
  • Physical & chemical
  • Human activities
• Macronutrients and micronutrients


  • CHOMPS (carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur)
  • Other vitamins and minerals
• Water cycle


  1. Evaporation

  2. Purification
• Carbon cycle


  1. Photosynthesis <- CO2

  2. Cellular respiration -> CO2

  3. Fossil fuels -> CO2
• Nitrogen cycle


  1. Denitrification

  2. Biological nitrogen fixation

  3. Industrial nitrogen fixation
• Phosphorus cycle


  1. Phosphate rock -> soil

  2. Marine sediments
• Ecological pyramids can be used to illustrate relationships between trophic levels.
• Pyramid of biomass - total mass of all living organisms at each level
• Pyramid of numbers - number of organisms at each level
• Biome


  A large, naturally occurring community of plants and animals occupying a specific habitat.
• Ecosystem


  A self-sustaining community of organisms interacting with each other and their physical environment.
• Denitrification


  The process by which nitrate ions (NO3⁻) are converted back into nitrogen gas (N2)
• Biological Nitrogen Fixation


  The process by which azotobacter bacteria convert atmospheric nitrogen (N2) into a form that can be used by plants, such as ammonia (NH3)
• Industrial Nitrogen Fixation


  The process of producing ammonia (NH3) through the reaction of nitrogen (N2) and hydrogen (H2) at high temperatures
• Autotrophs


  Organisms that produce their own food through photosynthesis or chemosynthesis, including plants, algae, and cyanobacteria.
• Only 10% of total energy is passed onto the next trophic level.
• Biosphere:

  the regions of the surface and atmosphere of the earth or another planet occupied by living organisms.
• 90% of energy is lost as heat or used by the organism, and is not passed onto the next trophic level.