1-5

• The ocean can be both a source and a sink for carbon
• Source


  Sends out more carbon than it takes in
• Sink


  Takes in more carbon than it sends out
• Nitrogen fixation


  1. Nitrogen gas converted to ammonia by bacteria

  2. Haber-Bosch process converts nitrogen gas to ammonia using fossil fuels
• Primary productivity


  Rate of converting solar energy into biomass or biological energy
• Only about 10% of energy is transferred from one trophic level to the next
• Higher net primary productivity

  More biomass for plants, more animals can be supported
• Tropical rainforest is the biome with the highest species richness for amphibians
• Describe question


  • Requires two parts: 1) Preferred conditions (e.g. more rainfall, warmer temperatures) 2) Why those conditions lead to higher biodiversity (e.g. more food, habitat, niches)
• Biodiversity


  Ecosystem diversity, species diversity (richness and evenness), genetic diversity
• Genetic diversity protects populations against environmental disruption
• Genetic diversity


  Protects a population against environmental disruption
• Potato subspecies


  • Many different genetic variations
  • Some impacted by blight, others survive
• If all potatoes are genetically identical, they will all fall victim to a disease and the whole population will be lost
• High species diversity allows ecosystems to recover more quickly from disturbance
• Biodiversity


  Like diversifying an investment portfolio, it helps hedge against risks
• Genetic diversity is important because if a species invests all of their genetic material on one exact genome, they are more likely to go extinct when there is a disturbance
• Categories of ecosystem services

  • Provisioning
  • Cultural
  • Regulating
  • Supporting
• Provisioning ecosystem services

  Physical products taken from the ecosystem, e.g. food, lumber, animals
• Cultural ecosystem services


  Non-material benefits people obtain from ecosystems, e.g. recreation, tourism
• Regulating ecosystem services

  Benefits obtained from an ecosystem's ability to regulate climate, water, disease, etc.
• Supporting ecosystem services


  Services necessary for the production of all other ecosystem services, e.g. nutrient cycling, soil formation
• The categories of ecosystem services are artificially created by humans and don't always fit neatly
• Islands closer to the mainland and larger in size generally have more species richness and biodiversity
• Provisioning ecosystem service provided by primary forests

  • Timber
  • Lumber
  • Wood
  • Medicine
  • Food
• Primary succession


  1. Pioneer species (e.g. lichen, moss)

  2. Intermediate species

  3. Climax community species
• Secondary succession


  Occurs when there is already soil present, after a disturbance like fire or flood
• Specialists


  Require specialized food and habitat, have a narrow niche
• Generalists


  Can thrive in a wide variety of conditions, have a broad niche
• Specialists are more likely to be negatively affected by habitat fragmentation because they have specific resource requirements
• Specialists cannot adapt quickly to changes because they have highly specialized adaptations to their environment
• Not all invasive species are r-selected, but r-selection does make a species more likely to become invasive due to high reproduction rates
• Ecological tolerance


  The range of environmental conditions an organism can tolerate, e.g. temperature, salinity, pH
• Organisms with a higher rate of reproduction are potentially prone to take over and exclude the food resources or habitat resources of another organism
• Homo sapiens can be considered the most invasive species in Earth's history
• Ecological tolerance


  How much an organism can take of temperature change, salinity change, pH change, etc.
• Ecological niche


  The range of conditions an organism thrives in and the role it plays in the ecosystem, including the range of food and habitat resources it can utilize
• More description would be needed to determine if ecological tolerance is different from ecological niche in this context
• 1. selected


  Organisms that have a high reproductive rate, short lifespan, and produce many offspring with little parental care
• 1. k selected

  Organisms that have a low reproductive rate, long lifespan, and invest heavily in their offspring