Download HES Biomes Notes Biomes- Groups of ecosystems with organisms

HES Biomes Notes
Biomes- Groups of ecosystems with organisms adapted to particular abiotic factors. So, abiotic factors
determine the biome.
Background Information
Global Processes Determine Weather and Climate
• Climate- The average weather that occurs in a given region over a long period- typically several
decades. Climate is what you expect.
• Weather- the short term conditions of the atmosphere in a local area. These include
temperature, humidity, clouds, precipitation, wind speed and atmospheric pressure. Weather is
what you get!
Earth's Atmosphere
• Atmospheric layers delineated by temperature
• Gasses w/constant proportions
o Nitrogen 78%
o Oxygen 21%
o Argon 0.09%
o Carbon Dioxide 0.039%
(390 PPM)
• Particulate Matter (PM)
o Ash
o Soot
o Pollen
o Mineral dust
o Salt spray
• EMS and the Atmosphere
o Radio  micro IR  visible  UV  X-rays  Gamma
o Main part of the spectrum absorbed the by ozone layer  UV
o Main part of the spectrum that reaches the Earth’s surface  Visible
o Main part of the spectrum that is radiated by the Earth’s surface and then absorbed by
GH gas gasses  IR
Terrestrial Biomes
Abiotic Factors that dictate Terrestrial Biomes
I.
Latitude- Earth/sun relationship; angle of rays; daylight hrs
 Angle of the Sun’s rays; Earth's Tilt and the Seasons
o The amount of the surface area over which the Sun’s rays are distributed.
o The variation in angle at which the Sun's rays strike
o The Earth's axis of rotation is tilted 23.5 ˚
o When the Northern Hemisphere is tilted toward the Sun, the Southern Hemisphere
is tilted away from the Sun, and vice versa.
II.
Global atmospheric circulation- Global patterns of air movement (Convection Currents) are
initiated by unequal heating of the Earth and are influenced by the Earth’s rotation and the
Coriolis Effect
 Unequal Heating of Earth
o As the Sun's energy passes through the atmosphere and strikes land and water, it
warms the surface of Earth. But this warming does not occur evenly across the
planet.
o Some areas of Earth reflect more solar energy than others.
o The % of incoming sunlight that is reflected from a surface is called its albedo.
 Earth's Rotation and the Coriolis Effect
o As Earth rotates, this causes a deflection of objects that are moving directly north or
south
 Air has four properties that determines its movement (convection currents)
o Density- less dense air rises, denser air sinks.
o Adiabatic heating or cooling- as air rises in the atmosphere its pressure decreases
and the air expands. Conversely, as air sinks, the pressure increases and the air
decreases in volume.
o Latent heat release- when water vapor in the atmosphere condenses into liquid
water and energy is released.
o Water vapor capacity- warm air has a higher capacity for water vapor than cold air.
III.
Global ocean circulation
 Global ocean currents are mainly a result of global wind patterns and also show
deflection due to the Coriolis Effect.
 The circular pattern of major ocean currents are called gyres.
 Gyres that cross latitudes, bring in warm or cold water into their new surroundings, and
affect climate in that region.
IV.
Coastal/Continental
 Specific Heat of Water
 Global atmosphere and ocean currents
V.
Topography- Mountain Effects & The Rain Shadow
 When air moving inland from the ocean that contains a large amount of water vapor
meets the windward side of a mountain range (the side facing the wind), it rises and
begins to experience adiabatic cooling.
 Because water vapor condenses as air cools, clouds form and precipitation falls.
 The presence of the mountain range causes large amounts of precipitin to fall on its
windward side.
 The cold, dry air then travels to the other side of the mountain range (the leeward side),
where it descends and experiences higher pressures, which cause adiabatic heating.
 This air is now war and dry and process arid conditions on the leeward side forming the
region called a rain shadow.
HES Biomes Notes
Aquatic Biomes
Background
 Largest part of biosphere
 Nearly 75% of Earth’s surface
 Boundaries between biomes indistinct
 More complex food webs than terrestrial biomes
o different depths add 3rd dimension to food webs
o photosynthesis confined to surface water
o difficult to study vast and deep ocean (Moon, Mars better studied than ~95% of ocean)
Marine Biomes
 Algae supply much of world’s O2
 Take in large amounts of CO2 (photosynthesis, gas dissolution)
 Avg 3.5% salinity (mostly Na+ and Cl-)
 Open ocean, Intertidal, Neritic, & Benthic zones
o Open ocean
 The depth that light can penetrate in the open ocean is dependent on the
amount of sediment and algae suspended in the water.
o Photic zone- the zone that receives enough light to allow
photosynthesis. Lowest P; Higher T, High DO, low CO2, phytoplankton,
some large nekton (whales, sharks) and many small nekton.
o Disphotic zone- Photic down to darkness; Temps down to 4°C; small
nekton rise to shallow water at night to feed.
o Aphotic zone- Deeper water that lacks light for photosynthesis; Low DO,
high CO2; High P; Temps near 4°C; nekton and benthos dependent
on“marine snow” – organic debris raining down from surface region;
unusual adaptation of bioluminescence.
 Chemosynthesis- The process that occurs in the aphotic zone
when some species of bacteria use methane and hydrogen
sulfide to generate energy.
o Intertidal
 Alternating wet/dry
 Narrow band of coastline between low and high tides
o Neritic
 Over the continental shelf
 Warm, shallow waters beyond the shoe
 Most diverse marine biomes- coral reefs and kelp forests
o Benthic
 Seafloor
Freshwater Biomes
 < 1% salinity
 Organisms that cannot survive larger salt concentrations
 Standing water (ponds, lakes)
o Littoral zone- the shallow area of soil and water near the shore where algae and
emergent plants grow.
o Limnetic zone- open water, where rooted plants can no longer survive. Phytoplankton
are the only photosynthetic organisms. This zone extends to as deep as sunlight can
penetrate.
o Profundal zone- the zone where sunlight cannot penetrate and therefore producers
cannot survive.
o Benthic zone- the muddy bottom of a lake or bond beneath the limnetic and profundal
zone.
 Flowing water (streams, rivers)
 Watersheds & Estuaries
Wetlands
 Boundary regions between terrestrial and aquatic biomes
 Regions of wet topographic depressions
 Tidal and Nontidal
Abiotic Factors that dictate Aquatic Biomes
I.
Salinity- Freshwater, Saltwater, or Brackish
II.
Flow- standing or moving
III.
Depth of light penetration
IV.
Temperature
V.
Pressure