Biology GCSE Ecology- Competition

• Food webs show the interconnectedness between organisms in an ecosystem through feeding relationships.
• Temperature affects plant growth by controlling enzyme activity and metabolic rate.
• Light is important because it provides energy to photosynthetic organisms through sunlight or artificial lighting.
• Imbalances in food webs can have ripple effects that disrupt the balance of an entire ecosystem.
• population is the total number of organisms of one species in a habitat
• community is the total population of different species living in a habitat
• Ecosystem is the interaction of community of biotic organisms with abiotic parts of their enviroment
• Plants compete for resources like light, space, water and mineral ions from the soil in order to survive and reproduce
• Animals compete for territory, food, water and mates in order to survive and reproduce
• interdependence is when in a community each different species within it depend on other species for food, shelter, pollination and seed dispersal
• Any major change in the ecosystem e.g. removal of a species can have far-reaching effects on interdependence
• effects of a loss of stonefly larvae in an ecosystem:

  1. less competition for algae- increases population of blackfly as they eat algae and more likely to be eaten by predators like water spiders who have a loss of prey (stonefly) = decrease in population
  2. water spider- have less food/prey-decrease in population
  3. stickleback- have less food since they prey on water spiders which are decreasing
• Stable communities = when all the species and enviromental factors are in balance so that population sizes are roughly constant e.g. tropical rainforests and oak woodlands
• Intraspecific competition occurs between members of the same species
• The intensity of competition depends on how many individuals are competing, how much resources there are available and how well adapted they are at obtaining them
• Interspecific competition is when two different species compete with one another.
• Succession is the gradual process whereby one type of vegetation replaces another over time
• Unstable communities= when there are fluctuations in numbers due to changes in environmental conditions or disturbances such as storms, floods, droughts etc.