BIOMES
TUNDRA
1. extreme northern latitudes
2. long harsh winters, very short summers
3. nutrient poor soils
4. permafrost
-permanently frozen ground
-interferes with drainage
-prevents roots of larger plants from becoming established
5. broad shallow lakes, ponds and bogs
6. lots of mosquitoes and black flies
7. regenerates very slowly...just hiking causes long
lasting damage
TAIGA
1. Boreal forest
2. In cold regions of Northern Hemisphere adjacent
to tundra
3. Dominated by conifers
4. Large mammals such as caribou, wolves, bear and
moose
TEMPERATE RAIN FOREST
1. Northwest coast of North America
2. Annual precipitation high, with dense coastal fogs
3. Small temperature range due to oceans moderating
effect
4. Evergreen trees (hemlock, Douglas fir, red cedar,
spruce)
5. Squirrels, deer, birds
6. Very rich wood producer
TEMPERATE DECIDUOUS FOREST
1. Hot summers/cold winters
2. Rich topsoil with deep clay rich layer
3. Dominated by broadleaved hardwood trees such as
oak, hickory, and beech that are deciduous
4. Virgin forest contained large mammals such as puma,
wolves, bison
5. Now contain bears, deer, small mammals and birds
6. Much of the original forests were logged
TEMPERATE GRASSLAND
1. Summers hot/winters cold: rainfall uncertain
2. Moist temperate grasslands: tallgrass
prairies in US (Iowa)
3. Rich soil supports grasses affected by periodic
wildfires
4. Once covered by herds of grazing animals such as
bison and pronghorn elk
5. Predators such as coyotes & wolves, with
prairie dogs, foxes, ferrets
6. Shortgrass prairies: less precipitation than tall
grass prairies (Montana)
7. More than 90% of the North American grasslands
have been subjected to agriculture
CHAPARRAL
1. Mediterranean climate: mild winter w/ abundant
rainfall, dry summers
2. Called Chaparral in North American southwest
3. Soil is thin, not very fertile.
4. Fires common in summer and fall
5. Dense evergreen shrubs, pine & scrub oak trees
DESERT
1. Dry areas in both temperate and tropical regions
2. Major daily temperature changes
3. Plant cover sparse: cacti, yuccas, Joshua trees
4. Animals small, remain under cover during the day
SAVANNA (TROPICAL GRASSLAND)
1. Grassland with widely scattered clumps of low trees
(Acacia)
2. Seasonal rainfall with prolonged dry periods
3. Herds of hoofed animals (wildebeest, antelope,
giraffe, zebra,elephants)
4. Large predators: lions and hyenas
5. Being converted to rangeland
TROPICAL RAIN FOREST
1. Temperatures are warm year-round, with precipitation
daily
2. Poor soils: organic matter cannot accumulate, high
temperatures foster rapid decomposition
3. Very high productivty
4. Most diversity of species of any biome
5. Trees form a dense multi-layered canopy, with shallow
matlike roots
6. Most varied insects, reptiles and amphibians on
earth
7. Mammals such as sloths and monkeys
8. Destruction likely by 2030
AQUATIC ECOSYSTEMS
1. Three types of organisms
A. Plankton: small or microscopic (phytoplankton &
zooplankton)
B. Nekton: large, swimming
C. Benthos: bottom dwellers
FRESHWATER ECOSYSTEMS
1. RIVERS AND STREAMS
A. Conditions change from source to mouth
Source: shallow, fast, cold, high DO
Mouth: deep, slow, warm, less DO
2. LAKE AND PONDS
A. Littoral zone: shallow water along the shore
-most productive zone/emergent vegetation & aquatic
plants
-frogs, turtles, worms, insects, fish
B. Limnetic Zone: open water away from shore
-plankton & larger fish
C. Profundal Zone: beneath Limnetic: no sunlight &
no plants...decomposers release nutrients that sit there producing mineral
rich zone
D. Fall turnover: as surface water cools, it
becomes denser and displaces the warmer mineral rich water below
E. Spring turnover: as surface ice melts, the denser
surface water sinks and displaces the bottom water
3.FRESHWATER WETLANDS
A. covered by shallow water for at least part of the
year
B. habitats for migratory waterfowl, beaver, otters,
muskrats, fish
ESTUARIES
1. Coastal body of water partly surrounded by land
with access to the open ocean and a large supply of freshwater from rivers
2. Very fertile ecosystems
3. Salt marshes: shallow swampy areas dominated by
grasses
4. Mangrove forests: found along tropical coastlines
INTERTIDAL ZONE
1. Area of shoreline between low and high tides
2. Very stressful zone