Bio test 1
Card Set Information
Bio test 1
ecology, physiological env, biomes, climate
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.
Air from equator pushed up towards poles
air curves to the right, s hem to the left.
Effects of mountains on climate
Decreasing air temp w/ ↑elevation
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.
Land use change
how humans have changed the land
evolution of unrelated species in response to similar selection pressures
broad leaves herbaceous plants
thick, tough, waxy, magnolia
Low-lattitude regions where precipitation
Warm, wet, no seaons. Rain has 2 main peaks w/
Soils are nutrient poor
Vegetation – Broad-leaved evergreen and
Up to 5 plant levels
i)emergent trees, evergreen trees, make up canopy
ii)lianas-woody vines & epiphytes –grows on
iii)Understory grow in the shade of the canopy
iv)Shrubs and forbs on forest floor.
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.
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
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
Most human-influenced biome. (b/c of ag and
Temperate shrublands and woodlands
Seasonability of precipitation
Woodlands (open canopy of short)
Wet winter, dry summer
Veggitation – evergreens, sclerophyllous leaves
Temperate Deciduous Forests
Found at 30-50o N along e and w edges
of Eurasia and e NA
Lower species diversity. Canopy trees, shorter
Fertile soils and climate are conducive to ag.
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
Some forests subject to fires, logging.
Boreal Forests (taiga)
Above 50o N, found only in the n
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
Occurs primarily in the arctic
Poleward decrease in temp and precip is
associated w/ the zones of high pressure generated by the polar atmospheric
Vegetation – sedges, forbs, grasses, low-growing shrubs like heaths willows and birches. Lichens and mosses.
when communities change over time
Orgs have 2 ways of changing
each species has a range of env tolerances that determine its potential geo distribution
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).
the total range of conditions that a species
needs to survive and reproduce
pops of the same species w/ adaptations to unique envs.
Energy balance equation for all animals
∆H= SR + IRin – IRout ± Hcond ± Hconv – Hevap + Hmet
heat exchange b/w 2 solids