Here you go
Explanation: A BIOME is a major geographical area characterized by a particular type of plants (flora) and animals (fauna). The major determining factor of what biome will exist in a particular place is CLIMATE. So let's talk about climate for a few minutes.
The ultimate source of climate is the sun, which provides not only the majority of energy on earth, but also creates climatic events when its randomizing energy interacts with the earth.
Less than half of the solar radiation striking the earth's atmosphere successfully penetrates the atmosphere to reach earth.
Terrestrial irradiance (that is, solar radiation that strikes the earth's surface) ranges from approximately 250nm (ultraviolet) to 1500nm (near infrared). Shorter and longer wavelengths are absorbed or reflected by atmospheric ozone, water vapor and other molecules.
When the sun is directly overhead in a cloudless sky, irradiance is most intense and peaks near 540nm ("green").
Environmental conditions and solar angle of incidence affect both intensity and spectral distribution of incident sunlight.
the TROPICS lie between the Tropic of Cancer (23.5o N) and the Tropic of Capricorn (23.5o S). These receive the highest annual input of solar energy, and are the only place on earth that the sun ever shines directly overhead (on the equinoxes, March 21 and September 21).
the SUBTROPICS lie between the Tropic of Cancer and 30oN in the northern hemisphere, and between the Tropic of Capricorn and 30oS in the southern hemisphere. (Miami is in the subtropics)
the TEMPERATE regions lie between 30oN and 60oN in the Northern Hemisphere and between 30oS and 60oS in the Southern Hemisphere.
the POLAR REGIONS lie above 60oN and S
Flora and fauna are profoundly affected by environmental and seasonal changes in solar intensity and spectral distribution. Note also that because the earth is tilted 23.5o on its axis (defining those tropical latitudes), there are seasons in both hemispheres:
Equinoxes (March and September): Day and Night are of equal length
Solstices (December and June): Longest and Shortest Days/Nights of the Year (depending on which hemisphere you're occupying)
Solar warming of earth creates
global air and water vapor movement
This creates climates typical of these regions:
TROPICS: Warm with high levels of precipitation
SUBTROPICS AND TEMPERATE: Comparatively warm and arid
HIGH TEMPERATE: Cool with high levels of precipitation
ARCTIC AND ANTARCTIC: Cold and arid (the polar regions)
Climate also can be affected by local topography:
proximity to ocean, lakes, rivers
mountains and valleys
Which can create smaller, localized ecosystems within biomes.
Major Aquatic Biomes
These occupy most of the biosphere.
Life originated in the oceans, and stayed there for nearly 3 billion years. The oceans are the most influential of all terrestrial features affecting climate and biomes.
Aquatic biomes may be
marine (average salinity 3%)
freshwater (average salinity 1% or less)
brackish (mixture of salt/fresh)
The major types of aquatic biomes are...
1. Freshwater:
lakes/ponds
rivers/streams
2. Freshwater or brackish:
estuaries
wetlands
3. Marine:
intertidal regions
coral reefs (the "rainforest of the sea")
oceanic pelagic zones
abyssal zones
Stratification of Aquatic Biomes by...
LIGHT
Light is absorbed by water and by living aquatic organisms
photic zone - light sufficient for photosynthesis
aphotic zone - light insufficient for photosynthesis
TEMPERATURE
Temperatures vary with depth, and aquatic habitats of any depth generally have a THERMOCLINE--a narrow band of water where temperature suddenly changes.
PRODUCTIVITY
Classification of Freshwater Biomes by Productivity As you will learn later, PRODUCTIVITY is a measure of how much biomass (dry organic matter) a particular ecosystem gains over a specified period of time.
oligotrophic - deep, nutrient poor, water very clear
eutrophic - shallower, nutrient rich, murky with phytoplankton
(a note on CULTURAL EUTROPHICATION)
mesotrophic - in between the above two classifications
Major Terrestrial Biomes
Polar/high mountain ice
Tundra (and more images of Tundra can be seen HERE.)
Coniferous (Boreal) Forest
Temperate Deciduous Forest
Prairie (Temperate Grassland) and more beautiful shots of Prairie can be seen HERE.
Savanna (Tropical/Subtropical Grassland)
Chaparral (Mediterranean Scrub Forest)
Tropical Rainforest
Desert (plus a view of Joshua Tree National Monument and Death Valley National Park. (plus some more artistic shots of Death Valley.
Plant types:
xeriphyte - plant adapted for survival in very dry habitats
hydrophyte - plant adapted for survival in very wet habitats
mesophyte - plant adapted for survival in moderate (not too wet, not too dry) habitats
Recall the link between soil nutrient content and precipitation.
Which of these biomes has the highest productivity?
Which has the highest and lowest soil nutrient content?
Which are most useful to humans for agriculture?
