Biotic & Abiotic factors

• if the availability of food falls, the number of organisms in that community will also fall
• how does new predators affect others?

  • population of preys will fall
  • existing predators will be competing for the same prey as new ones
• what is a species is outcompeted?

  its population can fall so much that numbers are no longer sufficient to breed and will become extinct
• if an infectious disease or pathogen spreads, it can wipe out a population of a species
• 4 biotic factors:

  • availability of food
  • new predators
  • competition
  • new pathogens
• how does light intensity affect plants?

  if light intensity decreases, the rate of photosynthesis decreases and plants grow more slowly = animals that feed on plants wont have enough food
• how does temperature affect species?

  • animals could migrate
  • plants might disappear from the area
• how does water affect species?

  • both animals and plants need water to survive
• why is the pH and mineral ions of the soil important for plants?

  plants cant grow on soul that is too acidic or alkaline and need nitrate minerals to make amino acids for protein
• how does the wind intenisty affect plants?

  strong winds can cause plants to lose water
• how does gases affect plants?

  • co2 is needed for photosynthesis = lack of co2 = rate of photosynthesis decreases
  • oxygen is needed for aerobic respiration= dissolved o2 in water can fall = harmdul to aquatic organisms
• 7 abiotic factors:

  • light intensity
  • temperature
  • water
  • pH and mineral content of soil
  • wind intensity
  • CO2 levels
  • O2 levels