Bio test 1

  1. Why are the tropics so warm/wet?
    • More direct solar radiation. As warm air rises
    • and cools, it can’t hold on to as much water vapor, aka clouds form.
  2. Hadley cell
    Air from equator pushed up towards poles
  3. Coriolus effect
    air curves to the right, s hem to the left.
  4. Effects of mountains on climate
    • Decreasing air temp w/ ↑elevation
    • Rain-shadow effect
    • Aspect-direction mountain faces (n-facing slopes are moister than s-facing slopes)
    • Inter-tropical convergence zone moves up&down equator, bringing wet season w/ it.
  5. Land use change
    how humans have changed the land
  6. Convergence
    evolution of unrelated species in response to similar selection pressures
  7. Forbs
    broad leaves herbaceous plants
  8. sclerophyllous
    thick, tough, waxy, magnolia
  9. Tropical Rainforests
    • Low-lattitude regions where precipitation
    • >2,000mm/yr

    • Warm, wet, no seaons. Rain has 2 main peaks w/
    • ITCZ

    Soils are nutrient poor

    • Vegetation – Broad-leaved evergreen and
    • deciduous trees.

    Up to 5 plant levels 

    i)emergent trees, evergreen trees, make up canopy

    • ii)lianas-woody vines & epiphytes –grows on
    • tree branches.

    iii)Understory grow in the shade of the canopy

    iv)Shrubs and forbs on forest floor.
  10. Tropical seasonal forests and savannas
    Wet and dry seasons, shifts with ITCZ

    • Large change in climate associated w/
    • seasonality of rain fall.

    • Vegetation – shorter, lower tree densities,
    • grasses, shrubs. Leaves can fall in dry season.

    Tropical seasonal biome

    Tropical dry forests

    • Thorn woodlands – widely spaced trees/shrubs. Found
    • b/w tropical dry forest&savanna climates. Thorns on trees.

    • Tropical savannas – fires and seasonal flooding
    • contribute to its formation.
  11. Hot Deserts
    • High temp, low rainfall. Located around the
    • descending air of Hadley cells.

    • Vegetation – succulent plants, dought-decidous
    • shrubs and grasses.

    • Desertification – Loss of plant cover and soil
    • erosion.
  12. Temperate grasslands
    • More seasonal temp variation than tropical
    • climates. Warm moist summers, cold dry winters.

    • Despite ample precip, fires/overgrazing keeps
    • trees from dominating the grasses.

    • Nutrient rich soil from all the decomposed
    • grasses/roots.
    • Most human-influenced biome. (b/c of ag and
    • grazing practices.
  13. Temperate shrublands and woodlands
    Seasonability of precipitation

    Woodlands (open canopy of short)

    “Mediterranean” climate

    Wet winter, dry summer

    Veggitation – evergreens, sclerophyllous leaves

    Fires common
  14. Temperate Deciduous Forests
    Deciduous leaves

    • Found at 30-50o N along e and w edges
    • of Eurasia and e NA

    • Lower species diversity. Canopy trees, shorter
    • trees/shrubs

    Fertile soils and climate are conducive to ag.
  15. Temperate Evergreen Forests
    Wide range of temp and precip

    Those with high precip, typically on w coast b/w 45o &50o  = temperate rainforests

    Nutrient-poor soils (evergreen leaves = acidic)

    • Lower diversity than deciduous&tropical
    • forest

    Some forests subject to fires, logging.
  16. Boreal Forests (taiga)
    • Above 50o N, found only in the n
    • hemisphere

    Extreme weather, subarctic regions.

    Permafrost – subsurface soil layer that remains frozen year round for at least 3 years

    Vegetation – coniferous species (spruces, pines, larches - deciduous needle trees)

    Least affected by humans
  17. Tundra
    Occurs primarily in the arctic

    • Poleward decrease in temp and precip is
    • associated w/ the zones of high pressure generated by the polar atmospheric
    • circulation cells

    Vegetation – sedges, forbs, grasses, low-growing shrubs like heaths willows and birches. Lichens and mosses.
  18. Succession
    when communities change over time
  19. Orgs have 2 ways of changing

  20. Fundamental principle
    each species has a range of env tolerances that determine its potential geo distribution
  21. Phys env influences orgs’ ecological success
    • Ability to obtain resources, maintain metabolic functions, grow, reproduce.
    • Extreme env conditions can impact survival
    • Geo distributions also influenced by the biotic env (competition, ect).
  22. Ecological niche
    • the total range of conditions that a species
    • needs to survive and reproduce
  23. Ecotypes
    pops of the same species w/ adaptations to unique envs.
  24. Energy balance equation for all animals
    ∆H= SR + IRin – IRout ± Hcond ± Hconv – Hevap + Hmet
  25. Conduction
    heat exchange b/w 2 solids
  26. Convection
    b/w liquids
Card Set
Bio test 1
ecology, physiological env, biomes, climate