Transcript Biomes_Aquatic_Ecosystems_Presentation

Biomes
By Drew Buzzell, Rebecca Forman
and Nina Sevilla
Objective Question:
What defines a biome?
• A biome is a terrestrial ecosystem that covers a large region
of the earth
• Characterized by communities of plants, animals and other
organisms that are adapted to its climate and other abiotic
factors
Tropical Forest
• Tropical forests occur near the equator where
temperatures are warm year-round
• One type of tropical forests--tropical rain forests--can receive
as much as 350 centimeters of rainfall yearly
• Tall broad-leaved trees create a canopy and little light
actually reaches the forest floor
• Tropical rain forests have the greatest diversity of life
o 50% of all species on Earth
• Clearing forests affects global weather patterns
Savanna
• Savannas are grasslands with scattered trees
• Found in tropical regions of Africa, Australia and South
America
• Grasses grow rapidly and are food for grazing animals
• Warm climate with alternating wet and dry seasons
o Organisms in the savanna must be able to cope with
drought
Desert
• Deserts are land areas that receive less than 30 cm of rain
per year
• Some have soil temperatures of over 60 degrees C, while
others are relatively cold
• Some have little to no plant life and others are populated by
scattered shrubs and cacti
Chaparral
• Temperate coastal biome dominated by dense evergreen
shrubs are known as chaparrals
• Climate consists of mild, rainy winters and hot, dry summers
Temperate Grassland
• Temperate grasslands are characterized by deep, nutrientrich soil that supports a varity of species and other plants
• Seasonal drought and occasional fires prevent woody
shrubs and trees from growing
• Drier areas have shorter grass species, but wetter areas
support plants that grow over 2 meters in height.
Temperate Deciduous Forest
• Temperate deciduous forests are characterized by dense
stands of deciduous trees (trees that drop their leaves each
year)
• Winters tend to be cold, and summers tend to be quite hot.
• New England falls into this category.
Coniferous Forest
• Coniferous forests are characterized by cone-bearing
evergreen trees (pine, spruce, fir, and hemlock)
• These regions are also called the taiga
• Winters are long, cold, and have heavy snowfall
• Typical animals are hares, moose, elk, wolves, and bears
Tundra
• Tundras are characterized by extremely cold temperatures
and high winds
• Found within the Arctic Circle and on high mountaintops at
all latitudes
• Permafrost is the permanently frozen subsoil, during the
summer only the first few inches melt
Aquatic Ecosystems
Background
• Nearly 3/4ths of the Earth's surface is covered with water
• Aquatic (water) ecosystems provide homes to many of the
Earth's organisms
• Major abiotic factors affecting aquatic ecosystems include
the amount of dissolved salt, the water temperature and the
availability of sunlight
Ponds and Lakes
• Standing (not flowing) bodies of water
• Photic zone is made up by the shallow water close to shore
and the upper zone of water away from shore
o Water plants and Phytoplankton--microscopic algae and
cyanobacteria that carry out photosynthesis--live in this
zone
• The aphotic zone is the deep, murky areas of a lake where
light levels are too low to support photosynthesis
• The benthic zone is what the bottom of any aquatic
ecosystem is called
o consists of rock, sand, and sediment
Streams and Rivers
• Bodies of flowing freshwater
o Streams are smaller, rivers are larger
• Near the source, river water is usually cold, low in nutrients,
and clear
o Few phytoplankton inhibit this part, instead the major
producer is algae on rocks
o Many species of anthropds live in the benethic zone and
the most common fish are trout
• Downstream the river becomes warmer, murkier, wider and
deeper
o Marshes and other wetlands are common
o More phytoplankton, as well as many other species,
inhabit this part
o Worms and insect larvae are more abundant in the
benethic zone
Estuaries
• An estuary is the area where a stream or river merges with
the ocean
• There are changes in slat concentration and temperature
• Nutrient rich soil supports a rich diversity of life, it is one of
Earth's most productive ecosystems
• Along the east coast of the United State, the major
ecosystems found in estuaries are salt marshes
• In tropical areas, the typical estuary ecosystems are
mangrove swamps
Objective Question:
Freshwater
Flowing
Aquatic
Ecosystems
Standing
Salt and Fresh
Water
Ocean Zones
• The ocean can be divided into zones based on depth
o Pelagic Zone (open water above the ocean floor)
 Photic, Aphotic
o Benethic Zone
• The ocean can also be divided into zones based on the
distance from shore
o Intertidal Zone
o Nertic Zone
o Oceanic Zone
Intertidal Zone
• Intertidal zone is the area of shore between high-tide and
low-tide
• Benethic organisms in this zone must be well-adapted to the
harsh conditions of the sun and wind during low tide and
pounding waves during high tide
o Ex. Barnicles
 cement themselves to rocks
 trap-door holds moisture during low-tide
Neritic Zone
• Neritic zone is the area of the ocean from the low-tide line
out to the edge of the continental shelf
• Sunlight allows for seaweeds and phytoplankton
• Other animals include mollusks, crustatians, sponges, sea
turtles, fish and marine mammals
Oceanic Zone
• Oceanic zone is the vast, open ocean from the edge of the
continental shelf outward
• The photic zone is inhabited by phytoplankton and
zooplankton (microscopic animals that serve as food)
• Swimming animals include dolphin, whales, squid and
numerous species of fish that are adapted to life at different
depths
Coral Reefs
• Visually spectacular and biologically diverse ecosystem
o Equivalent to tropical rain forests on earth
• Contain one out of every four marine species
• Usually in the neritic zone
• Most coral reefs are formed by colonies of coral polyps
Deep-Sea Vents
• Hydrothermal vents are spots on the ocean floor where hot
gasses and minerals escape from the Earth's interior
• No sunlight reaches this deep zone
• Vent communities use chemical energy from the Earth
o The producers in this ecosystem are prokaryotes that can
extract energy from sulfur compounds and use it to make
carbohydrates