Biomes

land biomes

Tropical Rainforest

• has the highest mean net productivity of any land biome

• found in all continents except for Europe and Antarctica

• characterized by tall trees and lots of rainfall, as well as a lot of biodiversity

• climate has consistent rainfall and temperatures throughout the year

Savanna

• moderate-high productivity, a lot of decomposition through termites occurs

• found in all continents except for Antarctica, and most frequently located in South America and Africa

• characterized by open grassland with scattered trees, high temperatures, and season drought

Desert

• low productivity due to low decomposition rates

• found in North America, South America, Asia, Africa, and Australia - covers 20% of the Earth

• characterized by a very dry climate (little rainfall) with little vegetation and constant high temperatures

• animals and plants adapted to conserve water

Temperate Grassland

• low productivity due to low temperatures in the winter and low levels of rainfall

• found in Australia, North America, South America, Europe, and Asia

• Characterized by relatively flat geography and large amounts of vegetation (think Midwestern U.S.)

• climate characterized by a wide range of temperatures: warm summers and cold winters, rainfall in the summer months

Temperate Deciduous Forest

• high productivity, nutritious soil that allows for tall trees

• can be found in North America, South America, Europe, and Asia

• has all four seasons, which causes temperatures to vary throughout the year

• characterized by tall trees and moderate temperatures, as well as moderate, consistent rainfall throughout the year

Boreal Forest

• low productivity due to its low temperatures and low rates of decomposition

• located in North America and Asia: the biggest land biome in the world

• composed of coniferous forests and freshwater bodies

• characterized by low precipitation, species diversity, and temperatures (permafrost -10ºC to 10ºC)

Tundra

• very low productivity due to the extremely low temperatures and harsh conditions

• found in the Northern regions of Europe, Asia, North America, as well as Antarctica

• very low biodiversity

• characterized by low temperatures, frost, and low-growing plants such as mosses and grasses.

aquatic biomes

freshwater biomes

• low salinity

• streams & rivers

  • flowing water has fewer plants, so the energy inputs come from terrestrial biome organic matter

• lakes & ponds

  • standing water

  • can be divided into depth zones (determined by how much light gets through)

    • littoral zone

      • algae + plants

      • most photosynthesis occurs

    • limnetic zone

      • open water

      • floating algae

    • profundal zone

      • no sunlight = no producers (low dissolved oxygen)

      • cannot support big organisms

    • benthic zone

      • muddy bottom

• freshwater wetlands

  • shallow and submerged for some time throughout the year

  • recharge groundwater while filtering pollutants

  • decrease flooding (slowly releases stored water)

marine biomes

• high salinity

• oceans, coral reefs, marshland, estuaries

• algae

  • supply a large portion of Earth’s oxygen and uptake CO2

  • primary producers of the oceans

• The distribution of marine natural resources, such as different types of fish, varies because of some combination of

  • salinity

  • depth

  • turbidity

  • nutrient availability

  • temperature

water reservoirs

• oceans are primary water reservoirs

• others include ice caps and groundwater (freshwater)

• replenished by precipitation runoff or infiltration

• only 2.5% of the world’s water is freshwater