RNR Lecture for test 2

  1. Grassland
    greater precipitation, major disturbances are drought and fire
  2. Tropical grasslands–
    –savannahs (Africa’s Serengeti Plain) many grass varieties are tied to rainfall wide spaced patches of drought resistant trees like the acacia
  3. Temperate grasslands–
    tall grass and short grass (Prairies of N. Am.), (Pampas of S. Am), (Veld of Africa), and (steppes of Europe)

    Only 1% of US tall grass prairies left, most converted to crop land and hog farms
  4. Short grass prairies, ....
    less H2O and nutrient availability– primarily rangeland or irrigated crop land

    • This land was left due to unable to plow and grow crops. Animals include the prairie dog, buffalo, and pronghorn antelope
    • Animals are migratory in lifestyle and so are their predators
  5. Polar grasslands–
    • arctic tundra. Covers 1/5 (20%) of the Earth’s surface. Cold, windy, 5" of precipitation/ year– snow (no rain)
    • Polar grasslands are really very cold deserts
  6. Talk more about polar grasslands
    • covered with lichens (cyanobacteria– an algae and a fungus), sedges, mosses, grasses, and low shrubs
    • -Decomposition slow, permafrost results in summer marshes
    • -Slow decomposition, shallow soil, slow plant growth
    • -Most fragile ecosystem in the world

    • Highly susceptible to human disturbance
    • Substantial engineering problems
  7. Forests–
    greater precipitation, less disturbance
  8. Tropical Rain Forests–
    • near the equator, warm year round, heavy rainfall, dominated by evergreen trees, water, heat, sunlight not limiting, soil nutrients low
    • **Greatest biodiversity per area on earth
    • Soils are poor, when leaves fall and are broken down the nutrients are taken up so quickly there is not build up of material.
  9. Tropical
    rain forest are only__-% of the earth’s surface, but produce ___% of timber, have ___% of all plants and animals
    other tropical forests with monsoon season
    dry season leaf loss leading to richer soils
    7%, 50, 50
  10. Temperate Deciduous Forests–
    • moderate temperatures, four seasons, abundant rainfall, dominant trees (oaks, hickory, maple, sycamore), nutrient rich soils from leaf fall
    • 0.1% old growth forests left in the lower 48 states
    • Note: an old growth forest has never been harvested
  11. Chapparal -
    unique ecosystem between dry and wet climates
  12. Boreal forests -
    slow tree growth, acidic soils from evergreen needleleaf trees
Card Set
RNR Lecture for test 2
lecture questions that i have the ansers for so far