Transcript The biosphere - Science Class: Mrs. Boulougouras

THE BIOSPHERE
BIOSPHERE
• All organisms and the part of the Earth where
they exist
• Hydrosphere: collection of Earth’s water
bodies, ice, and water vapor
• Atmosphere: air blanketing Earth’s solid surface
• Geosphere: features of Earth’s surface-such as
continents and the sea floor-and everything
below Earth’s surface
BIOTIC AND ABIOTIC
FACTORS INTERACT IN THE
BIOSPHERE
CLIMATE
• Average long-term weather pattern of a
region
• Microclimate: climate of a specific
location within a larger area
CLIMATE
• Temperature
– Most organisms are adapted to live within a particular range
of temperatures and will not thrive outside of that range
– For example: the growing season of plants is primarily
influenced by temperature
• Moisture
– All organisms require water
– On land, water can be scarce and rainfall often determines
an area’s life-forms
EARTH HAS THREE MAIN
CLIMATE ZONES
• Polar
• Tropical
• Temperate
– Influence of sunlight
– Air and water movement
– Landmasses
– Adaptations to climate
EARTH
HAS 6
MAJOR
BIOMES
BIOME
• A large region characterized by a specific type of
climate and certain types of plant and animal
communities
TROPICAL RAINFOREST BIOME
• Annual rainfall: 450 cm (180 in)
• Greatest number of species
compared to any other biome
• May contain at least ½ all of the
Earth’s species of terrestrial
organisms (more than 2 million
species)
• Infertile soils but high primary
productivity
GRASSLAND BIOMES
• Tropical grasslands
– Temperatures warm throughout the
year
– Tall grasses, scattered trees and
shrubs
– Hoofed animals
• Temperate grasslands
– Dry and warm during summer; snowy
winters
– Short or tall grasses, depending on
precipitation
– Many animals live below the surface
to survive dry, windy conditions
DESERT BIOME
• Annual rainfall: less than 25 cm
(10in) each year
• The scarcity of water is the
overriding factor influencing most
biological processes in the desert
• The vegetation is characteristically
sparse
• Most extensive in the interiors of
continents
TEMPERATE FOREST BIOMES
Temperate Deciduous Forest
• Relatively mild climates and
plentiful rain
•
Grow in areas with relatively
warm summers, cold winters
•
Annual rainfall: 75-250 cm (30100 in)
•
Cover much of the eastern USA
•
Home to deer, bears, beavers,
raccoons, etc.
Temperate Evergreen/Tropical Forest
• Found in other temperate areas
•
Drier weather and different soil
conditions favor the growth of
evergreens
•
Large portions of the
southeastern and western USA
have temperate evergreen
forests
•
Where conditions are even drier,
forests give way to areas of dry
shrubs, such as in the chaparral
areas of coastal California and in
the Mediterranean
TAIGA BIOME
• Cold, wet climates promote the growth of coniferous
forests
• Extends across vast areas of Eurasia and North America
• Winters are long and cold
• Most precipitation occurs in the summer
• Many large mammals, including herbivores such as elk,
moose, deer and carnivores such as wolves, bears and lynxes
live in the taiga
TUNDRA BIOME
• Between the taiga and the permanent ice surroundings of the
North Pole is the open, boggy tundra
• Covers 1/5th of the Earth’s land surface
• Annual precipitation: less than 25 cm (10 in)
• Water is unavailable for most of the year because it is frozen
• The permafrost, or permanent ice, usually exists within 1 m (3
feet) of the surface
• Foxes, lemmings, owls, and caribou are among the inhabitants
MINOR BIOMES
• Chaparral: biome characterized by hot,
dry summers and cool, moist winters;
also called Mediterranean shrub-land
POLAR ICE CAPS AND MOUNTAINS
ARE NOT CONSIDERED BIOMES
• Polar ice caps have no soil and no
specific plant community
• Mountain climate, animals and plants
change with elevation
MARINE ECOSYSTEMS
• The ocean can be divided into zones
MARINE ECOSYSTEMS
• Intertidal Zone: strip of land between high and low tide lines
• Neritic Zone: zone that extends from the intertidal zone out to
the edge of the continental shelf
– Plankton: microscopic, free-floating organisms,
which may be animals or protists
– Zooplankton: animal plankton
– Phytoplankton: photosynthetic microscopic protists, such as algae
• Bathyal Zone: zone of the ocean that extends from the edge of
the neritic zone to the base of the continental shelf
• Abyssal Zone: depth of the ocean that lies below 2000 meters
and is in complete darkness
COASTAL WATERS CONTAIN
UNIQUE HABITATS
• Coral reef: ocean habitat
found in the shallow coastal
waters in the tropical climate
• Kelp forest: ocean habitat that
exists in cold, nutrient-rich
shallow coastal waters,
composed of large communities
of kelp, a seaweed
ESTUARY CHARACTERISTICS
• Estuaries are dynamic
environments where rivers flow
into the ocean
• Estuary Characteristics
– Refuge for many species
– Spawning grounds
• Threats to Estuary Ecosystems
– Loss of habitat
– Coastal erosion
FRESHWATER COMMUNITIES
• Freshwater ecosystems include moving and
standing water
• Lakes, ponds, streams, and rivers cover only 2%
of the Earth’s surface
• All freshwater habitats are strongly connected
to terrestrial ones, with freshwater marshes and
wetlands constituting intermediate habitats
• Many organisms are restricted to freshwater
habitats including fish, plants, arthropods,
mollusk, and other invertebrates
FRESHWATER COMMUNITIES
• Littoral Zone
– A shallow zone in a freshwater
habitat where light reached the
bottom and nurtures plants
– Inhabitants: Aquatic plants,
predatory insects, amphibians,
small fish
• Limnetic Zone
– The area in a freshwater habitat
that is away from the shore but
still close to the surface
– Inhabitants: floating algae,
zooplankton, fish
FRESHWATER COMMUNITIES
• Profundal/Benthic Zone
• The zone in a freshwater
habitat to which little
sunlight penetrates
• Inhabitants: numerous
bacteria, wormlike organisms
that eat debris on the
bottom
• Not all freshwater systems
are deep enough to have a
profundal zone
WETLANDS
• Swamps, marshes and bogs
• Covered with a layer of water
• Contain a variety of water-tolerant plants
• Dynamic communities that support a diverse array of
invertebrates, birds, and other animals
• One of the most productive ecosystems on Earth, exceeded
only by coral reefs in diversity and concentration of species
• Key role in water storage basins that moderate flooding