Unit 5: Biomes and Aquatic Ecosystems (Ch. 6)

What is a Biome?

• Groups of terrestrial ecosystems that share biotic and abiotic conditions

• Biomes are primarily defined by their _______________ & typical ____________ & _____________ life.

Climate

• Climate – describes the ______________ conditions, including _________________ & __________________ over long periods in a given area.

• Weather - _____________ conditions in Earth’s atmosphere Ex. Sunny & Humid

• Climatograph – climate diagram that shows conditions in a biome (temperature & precipitation).

• Temperature is usually in _____________°F = 1.8°C + 32

• Precipitation is usually in cm or mm.

• 1 inch = 2.54cm

• 1 inch = 25.4 mm

• Each biome has a set of characteristic _________________ adapted to its particular climate conditions.

• However, within any biome there is a variety of plants and animals due to variation in ______________, ______________ & ___________________

• Patches representing the same biome tend to occur at similar _______________

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10 primary biomes

• tropical rain forest

• dry forest savanna

• desert

• temperate rain forest

• temperate forest

• chaparral

• temperate grassland

• chaparral

• boreal forest (taiga)

• tundra

Net Primary Production

• ___________ primary production: The rate at which primary producers undergo photosynthesis and produce usable energy

• ______ primary production: The amount of organic matter (biomass) that remains after primary producers use some to carry out cellular respiration

• Ecosystems vary in their net primary productivity.

• _________ _________ biomes generally have ____________net primary productivity than __________ _________ biomes.

• This should make sense because plants require _______________, ____________ & warm enough temperatures to grow.

Tropical Rain Forest

• Year-round _________ temperatures and at least _____________ precipitation a year

• Near the equator, so the days are almost always ____________ in length.

• Soil is generally ____________________

• The tallest trees pop through the canopy and make up the ___________________

• Tall trees form a dense layer called the ______________ which keeps the forest warm and damp.

• Short trees and plants make up the _________________ and must compete for light.

• _________________leaves are a common adaptation to increase sunlight intake.

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ADAPTATIONS

• _______________ - plants that grow on other plants instead of the soil. Ex. Orchids

• Tall trees use ________________ (large above ground roots) for support

• Because there is not much _______ to assist with pollination, plants have adapted bright, colorful flowers to attract pollinators.

• Supports ________ animal species than any other biome; animals tend to be highly ________________.

Tropical Dry Forest

• Warm year-round, but rainfall is highly seasonal with a ________ & ________ season.

ADAPTATIONS

• Most trees are _______________ - they lose their leaves and cease photosynthesis part of the year. This helps reduce _________________.

• Plants and animals exhibit adaptations (e.g. waxy leaf coating, deep roots, estivation, migration) that enable them to survive the dry season.

• ________________ - animals enter a deep, sleeplike period of dormancy.

Savanna

• Receives _______ precipitation than tropical dry forests, but more than deserts; usually has a distinct ________ season

• ______________ interspersed with groups of trees

• Tree growth limited by frequent __________ and strong _________

ADAPTATIONS

• Plants are adapted to dry conditions; tend to be ________________ with deep roots, thick bark, and __________ coatings on leaves.

• Elephants drink 30-50 gallons of water a day and so they must dig for water with their tusks.

• Many animals _____________ to find water, or burrow when water is scarce.

Desert

• Receives less than 25 cm (9.8 in.) of precipitation per year (____________ biome)

• Temperatures vary widely from _______ to ___________.

• ADAPTATIONS

• Plants tend to have __________, leathery leaves

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• Plants store water in their tissues (_________________) Ex. Aloe

• Some have shallow, spread out roots to gather water.

• Some have deep tap roots (up to _____ ft)

• Tough ____________ (modified leaves) discourage predators from eating them

• Animals get most of their water from the _________ they eat, and they tend to be _______________ (active at night).

• Some have concentrated ________.

• Mammals have exaggerated ___________________ to help regulate body temperature.

Temperate Rain Forest

• Year-round _____________ temperatures and heavy ____________.

• Largest extent found in ____________________________

ADAPTATIONS

• Characterized by tall _________________ trees, such as cedars and hemlocks, that don’t lose leaves annually; many are conifers (produce seed-bearing cones)

• Forest floor is shaded, damp, covered in ________.

• Animals that require ______________, such as amphibians, thrive here.

• Squirrels, deer, elk and birds have a __________ diet which enables them to eat whatever food is available.

Temperate (Deciduous) Forest

• Precipitation ______________________throughout the year

• Varied temperatures (________ summers, _______ winters)

ADAPTATIONS

• Plants tend to be broad-leafed and _______________.

• Soil is enriched with ______________ from annual leaf drop.

• Animals may _____________ or ______________

• Others ________________ to survive cold conditions.

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• __________________ helps animals that are exposed during the winter due to lack of foliage survive.

Temperate Grassland (Prairie)

• Moderate seasonal ___________________ and fairly extreme seasonal ____________________; droughts and fires common

• Rich, fertile soil

ADAPTATIONS

• Not enough precipitation to support large ____________

• ______________, which grow from their base, thrive despite droughts, fires, animals grazing.

• Seeds are dispersed by the ____________________

• Soil tends to be rich in nutrients; most of world’s grasslands have been converted to ______________.

• Animals are adapted to deal with lack of _________.

• Some survive by _________________.

• Others survive by being _________.

Chaparral (Mediterranean)

• Highly seasonal conditions with _______________ winters and _______________ summers

• Prolonged hot, dry periods; ________________________ common

• Soil is thin and not rich in nutrients

ADAPTATIONS

• Plants are drought-resistant; many have thick, waxy __________ or leaves with __________ that trap moisture; _________________ are common.

• Plants may have thick __________ and deep __________ to resist fire.

• Some plants require __________ to germinate.

• Some chaparral plants contain ________ compounds that facilitate the spread of fire.

• Many animals _____________.

• Many are nocturnal to avoid heat.

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• Many have ________________ appendages

Boreal Forest (Taiga)

• _________________ winters; _________________ summers

• Nutrient-poor, slightly acidic soils

ADAPTATIONS

• _________ species diversity

• Coniferous trees with __________ needles and _____________ shape, adapted to harsh, snowy conditions are common.

• Animals feed, breed, and care for young mostly during short _________ season

• Year-round residents tend to have thick insulation and small extremities that maintain heat.

• Some animals change color. They grow _______________ for the snowy season.

Tundra

• Extremely ________________ winters; relatively sunny and cool summers

• Found at very __________ latitudes in the Northern Hemisphere

• Harsh _________, nutrient-poor soil, and freezing temperatures limit plant growth; no tall trees; mosses and lichens common

• Characterized by __________________ (underground soil that is frozen ___________________)

ADAPTATIONS

• Low, scrubby vegetation and ground-hugging ______________ & _____________ live here.

• Birds and ______________ migrate to the tundra during the mild summer to feed on insects and lichens

• Only a few species live here year-round (including musk oxen and polar bears).

Places that are Not Classified as Biomes

Polar Ice

• No land under polar ice in Northern Hemisphere; ice sits atop Antarctica in Southern Hemisphere

• Very few plants; most life is in surrounding ocean

Mountains

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• Mountain communities change with _______________, similar to how biome communities change with latitude.

Aquatic Ecosystems

• Normally, biomes are used to describe ___________________ environments but 75% of Earth is covered in water.

• Aquatic Ecosystems are described by their ______________, _____________ and movement of water.

• Salinity: the amount of dissolved ______ present in water.

• Measured in parts per thousand (ppt)

• Salt water = _________ppt

• Fresh water = 0.5ppt or less

• Brackish = Between __________ppt

• Photosynthesis tends to be limited by _________ availability, which is a function of depth and water clarity.

• Aquatic ecosystem zones: photic, aphotic, benthic

• Photic zone: Where there is enough light for ______________________.

• Aphotic zone: Photosynthesis cannot occur because there is not enough sunlight

• Benthic zone: Very ____________ of the body of water

• The photic zone has much more dissolved ____________, so more life is found here (both producers and consumers).

• Sunlight also causes water to be _____________

• ______________ layers of aquatic ecosystems tend to be warmer than _____________ layers

Freshwater Ecosystems: Ponds, Lakes & Inland Seas

• Salinity is less than 0.5 ppt (parts per thousand)

• Includes _______________________________________

• Ponds and lakes are similar, except in ______

• Inland seas are huge and contain organisms adapted for _________ water. Ex. Great Lakes and The Caspian Sea

• Ponds and lakes are divided horizontally into 2 zones: littoral and limnetic.

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• Littoral Zone – water is ______________ enough for plants to grow from the mud to above the water’s surface

• Includes many invertebrates like ____________________

• Limnetic Zone – ____________from shore where there are no rooted plants

Freshwater Ecosystems: Wetlands

• Wetland - Area of land _______________ with water at least _________________________

• Includes freshwater ________________________________________________

• Water can either ______________________ through wetlands or into other bodies of water or, it can remain _____________

• Freshwater Marsh – shallow-water wetland characterized by ________________ plants. Ex. Cattails and Bulrushes

• Swamp – shallow water wetland characterized by woody ______________________ instead of grasses. Ex. Cypress Trees

• _____________ cause the formation of swamps by building __________ across streams and causing flooding upstream.

• Bog – wetland characterized by low nutrients, acidic water and thick floating mats of vegetation (usually ________)

• Fen – Similar to a bog but connected to a source of ___________________, less acidic and more nutrient rich

Benefits of Wetlands

• They help prevent ______________ by absorbing excess water

• Recharge ________________

• Filter _________________ & __________________

• Provide habitats for many _________________

Freshwater Ecosystems: Rivers & Streams

• Bodies of surface water that flow _______________, eventually reaching an ocean or a landlocked body of water

• _____________ - a small river flowing into a larger one

• _________________: The area of land drained by a river and its tributaries

• Rivers shape the ________________ through which they run.

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• The ___________ or beginning of ________ rivers is high in the mountains where melting snow collects due to ____________

• Characteristics of the source

• _____________

• _________________________

• _________________________

• _____________________________________

• Characteristics of a river as it leaves its source.

• ___________________

• ___________________

• ___________________

• ___________________

• ___________________

• ___________________

• _________________– area near a river’s course that is periodically flooded

• __________ – where the river empties

Estuaries

• Occur where a river flows into the _________ or a freshwater body of water

• Coastal estuaries are _______________ ecosystems; organisms must tolerate wide salinity and temperature ranges.

• Some estuaries (like the _______________________) contain only __________________.

Two types of estuary ecosystems:

1) ____________________ – along coasts at temperate latitudes

Characterized by salt-tolerant grasses

2) ________________________– along coasts at subtropical and tropical latitudes

Include mangrove trees

Benefits of Estuaries:

1) Prevent __________________ & __________________

2) Protective barrier between ________ & __________

3) Home to many ______________, some which are commercially beneficial

Destruction of Estuaries:

• Many are being destroyed for housing and commerce

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• Flooding from Katrina was significantly worse where the salt marshes had been destroyed

Oceans

• All of the Earth’s major oceans combined occupy _______ of the Earth’s surface.

• If we evaporated all of the water from the oceans, there would be a layer of salt approximately ___________ deep left.

• Currents are driven by ___________________________ and ____________________________, wind, and gravity.

• Water density increases as temperature _______________ and salinity (salt content) _________________.

• Heavier (________________________) water sinks

• Lighter (_________________________________) water remains near the surface.

• Surface winds and heating generate _______________ currents that transport nutrients and oxygen.

• __________________ - the flow of cold, nutrient rich water towards the surface. It occurs when horizontal currents _______________ (flow apart).

• ____________________ - the flow of warm water, full of dissolved gases away from the surface, into the deep ocean. It occurs when horizontal ocean currents ________________ (flow together).

Ocean Ecosystems

1) ______________: Highly diverse; extreme range of temperature, moisture, and salinity.

2) ___________: Extends from the low tide mark to the edge of the ____________________________.

• Two productive ecosystems exist here:

• ________________ - large brown algae grows from the continental shelf.

• ________________ - Exists in subtropical and tropical waters. A mass of ____________________________ composed of ______________ of marine coral.

3) Open ocean: Begins at the edge of the ___________________ shelf

• Makes up _______ of the Earth’s oceans

• Low productivity due to low ___________________________

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• ______________________ are at base of food chain

• Includes jelly fish, whales, sea turtles, squids, large fish & sharks.

• In the aphotic open-ocean, animals have many adaptations to help them survive.

• Ex. ______________________________

• Ex. ________________________ - sometimes a symbiotic relationship with bacteria

• Benthic Ecosystems around _______________________ vents (hot water flows out from the sea floor) are home to come strange organisms.

• Bacteria use chemicals to make energy (AKA ________________________)

• Other organisms like ___________________ are in a symbiotic relationship with the bacteria and survive using the energy they make.

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