Lesson 2

• Energy flow in an ecosystem is defined as the movement or transfer of energy from one trophic level to another in an ecosystem. The energy that is passed is in the form of chemical energy.
• Energy flow is responsible for sustaining life on this planet. 
• The nutrient cycle is a system where energy and matter are transferred between living organisms and non-living parts of the environment.
• ecological succession is a sequential process of rebuilding the ecosystem because of the disaster
• primary succession has a lifeless area because of lava and it also barren community full of rocks
• secondary succession has a community before and disaster happen so back to zero
• Mountain ecosystem - altitude.
• Grassland ecosystems- vegetation grasses.
• Marine ecosystems are aquatic environments with high levels of dissolved salt
• estuarine where river meets the sea
•  fresh water is found in the surface water of lakes, rivers, and swamps
• Terrestrial ecosystem is land based
• Aquatic ecosystem is water based
• agroecosystem support farms and gardens. it is manmade
• biome is a distinct geographical region with specific climate, vegetation, and animal life. 
•  biological community - group of individuals of the same species that live together in the same area at the same time. 
• Biomes of the World

  • Tropical Rainforest.
  • Temperate Forest.
  • Desert.
  • Tundra.
  • Taiga
  • Grassland.
  • Savanna
  • Marine
• ecosystem - A community of living things interacting with non-

  living things
• Eco =home

  systems=interacting parts
• Studies by ecologists
• Must have:

  -water

  -nutrients

  -shelter
• Primary parts of an ecosystem:

  Abiotic = non-living things

  Biotic = living things.
• levels of ecological organization (pyramid)

  1. biosphere
  2. ecosystem
  3. community
  4. population
  5. organism
• food chain - Transfer of food energy from the source
• food web - Interconnected relationships among food chains in an

  ecosystem
• Ecological pyramids show the relative amounts of various parameters (such as number of organisms, energy, and biomass) across trophic levels.
• Biogeochemical cycles mainly refer to the movement of nutrients and other elements between biotic and abiotic factors.