FRESHWATER BIOMES Ecology Chapter 10. Aquatic Biomes Water covers more than 70% of the Earth’s surface Aquatic habitat: one in which organisms live.

FRESHWATER BIOMESFRESHWATER BIOMES

EcologyEcology

Chapter 10Chapter 10

Aquatic BiomesAquatic Biomes

Water covers more than Water covers more than 70%70% of the of the Earth’s surfaceEarth’s surface

Aquatic habitatAquatic habitat: one in which : one in which organisms live in or on waterorganisms live in or on water not grouped geographicallynot grouped geographically difficult to show on a map difficult to show on a map often determined by often determined by depthdepth rather than rather than

locationlocation

Land vs. Aquatic BiomeLand vs. Aquatic Biome

TemperatureTemperature and and rainfallrainfall are important are important factors when distinguishing one factors when distinguishing one landland biome from another.biome from another.

Temperature in large bodies of Temperature in large bodies of waterwater are are relatively relatively stablestable..

Rainfall has Rainfall has less effectless effect on aquatic biomes on aquatic biomes because organisms are already because organisms are already underwater.underwater.

Important Factors Important Factors

SalinitySalinity: The amount of dissolved salts in : The amount of dissolved salts in a sample of water. Measured in a sample of water. Measured in parts per parts per thousandthousand (# units of salt in a thousand (# units of salt in a thousand units of water)units of water)

Aquatic biomes can be divided into Aquatic biomes can be divided into twotwo main groupsmain groups SaltwaterSaltwater (30 parts/1000) (30 parts/1000) Freshwater Freshwater (0.5 parts/1000)(0.5 parts/1000)

• Brackish water > saline than fresh, < saline than Brackish water > saline than fresh, < saline than ocean waterocean water

Important FactorsImportant Factors

DepthDepth – directly related to the amount of – directly related to the amount of sunlightsunlight that reaches the bottom of the that reaches the bottom of the body of water.body of water. Sunlight determines the Sunlight determines the types and amounts types and amounts

of plantsof plants that can grow. (Remember – plants that can grow. (Remember – plants are producers, and the base of the food web)are producers, and the base of the food web)

PhoticPhotic zone zone: top layer of sunlight that receives : top layer of sunlight that receives enough sunlight for photosynthesis to occur.enough sunlight for photosynthesis to occur.

Aphotic Aphotic zonezone: below the photic zone. Sunlight : below the photic zone. Sunlight does notdoes not reach this zone. reach this zone.

BenthicBenthic zone zone: the floor of a body of water: the floor of a body of water

Question BreakQuestion Break

1.1. What characteristic distinguishes the What characteristic distinguishes the photic zone from the aphotic zone?photic zone from the aphotic zone?

SunlightSunlight

2.2. How is salinity measured?How is salinity measured?

Parts per thousand (# units salt/1000 Parts per thousand (# units salt/1000 units of water)units of water)

Standing-water EcosystemsStanding-water Ecosystems

The most common types of standing-water The most common types of standing-water ecosystems are ecosystems are lakes and ponds.lakes and ponds. Also includes Also includes wetlandswetlands (bogs, swamps, etc.) (bogs, swamps, etc.)

While there is no flow of water in and out While there is no flow of water in and out of most standing-water ecosystems, there of most standing-water ecosystems, there is a is a circulationcirculation of water throughout the of water throughout the system. system. Review question: How does this circulation Review question: How does this circulation

occur? What causes the circulation?occur? What causes the circulation?

Abiotic Factors Biotic Factors

Deepest type of standing water;may have an aphotic zone; may be fed by aquifers

Floating algae in the photic zone, plants along shoreline, complexfood webs

Light reaches benthic zone; fed by rainfall – may be seasonal

Main producers – plants and algaethat grow on bottom; food websimpler than lakes

Plants have roots under water, leaves above water; grasses,cattails; ducks and waterfowl

Very shallow water, land occasion-ally exposed; saturated soil; FloridaEverglades largest freshwater marsh

Land soaked due to poor drainage;usually along low streambeds andflat land

Large trees and shrubs; cypresstrees in south, willow and dogwoodin north

Inland wetland; soil is acidic; decayis slow

Sphagnum moss dominant organ-ism, partly decayed moss accumu-lates as peat

Lake

Pond

Marsh

Swamp

Bog

Types of Standing-Water Ecosystems

Standing-Water OrganismsStanding-Water Organisms Several levels of habitatSeveral levels of habitat

PlanktonPlankton community community• PlanktonPlankton:: microorganisms that float on the surface of the water microorganisms that float on the surface of the water

PhytoplanktonPhytoplankton: : carry out photosynthesis. Main carry out photosynthesis. Main producersproducers in most in most aquatic biomesaquatic biomes

ZooplanktonZooplankton:: do not carry out photosynthesis. Include microscopic do not carry out photosynthesis. Include microscopic animals and protozoans. animals and protozoans. ConsumersConsumers – feed on phytoplankton – feed on phytoplankton

Big fish feed on little Big fish feed on little fish, little fish feed onfish, little fish feed onplankton plankton

BenthicBenthic community community• ScavengersScavengers, depend upon a steady rain of organic material that drifts , depend upon a steady rain of organic material that drifts

down from the top. down from the top. DecomposersDecomposers are also part of this community are also part of this community

WetlandsWetlands

Ecosystems in which the Ecosystems in which the rootsroots of plants of plants are submerged under water at least part are submerged under water at least part of the year. Soils are soaked with water, of the year. Soils are soaked with water, and very low in and very low in dissolved oxygendissolved oxygen.. Marshes, swamps, bogsMarshes, swamps, bogs Act as Act as filtersfilters, detoxifying chemicals that , detoxifying chemicals that

passes through thempasses through them• Can be used as part of a treatment system for Can be used as part of a treatment system for

waste waterwaste water Important breeding, feeding, and resting Important breeding, feeding, and resting

grounds for waterfowl.grounds for waterfowl.

Endangered WetlandsEndangered Wetlands

Wetlands are being destroyed by Wetlands are being destroyed by human activity.human activity. Many do not find wetlands as attractive Many do not find wetlands as attractive

as other natural habitatsas other natural habitats Land (especially in coastal areas) is Land (especially in coastal areas) is

developed for resorts and homesdeveloped for resorts and homes Swamp Lands Act of 1849Swamp Lands Act of 1849

encouraged the filling and draining of encouraged the filling and draining of wetlandswetlands

Florida EvergladesFlorida Everglades

Once a swampy marsh that covered 160 Once a swampy marsh that covered 160 km from Lake Okeechobee to the tip of km from Lake Okeechobee to the tip of Florida.Florida.

Region has a Region has a wet seasonwet season from May to from May to October, followed by a October, followed by a dry seasondry season. . Natural fires occur during the dry Natural fires occur during the dry season, burning off dried plant material.season, burning off dried plant material.

Home to a large number of organisms, Home to a large number of organisms, that are adapted to the annual cycle of that are adapted to the annual cycle of growth, drought, and fire.growth, drought, and fire.

In 1983, “In 1983, “Save Our EvergladesSave Our Everglades” ” campaign was launched. campaign was launched. 100,000 acres returned to wetland100,000 acres returned to wetland Flow of water adjusted to provide a Flow of water adjusted to provide a

more natural water supplymore natural water supply

Flowing-Water EcosystemsFlowing-Water Ecosystems

Rivers, streams, creeks, brooksRivers, streams, creeks, brooks All water that flows over All water that flows over landland - to a - to a

scientist they are all scientist they are all streamsstreams Water that flows Water that flows undergroundunderground is an is an

aquiferaquifer Stream OrganismsStream Organisms

Adapted to the Adapted to the rate rate of the water’s of the water’s movementmovement• Hooks to grab hold of plantsHooks to grab hold of plants• Suckers that anchor to rocksSuckers that anchor to rocks

Stream StagesStream Stages

________:________: RapidsRapids WaterfallsWaterfalls Fast-moving waterFast-moving water Steep slopeSteep slope

_______:_______: Broad floodplainBroad floodplain MeandersMeanders Oxbow lakesOxbow lakes Meander ScarsMeander Scars

Youthful Old

Important DefinitionsImportant Definitions

____________ – a stream and all its ____________ – a stream and all its tributariestributaries

________ – a smaller stream that empties ________ – a smaller stream that empties into a larger streaminto a larger stream

_________ – the land area drained by a _________ – the land area drained by a river systemriver system

______ – a high point that separates river ______ – a high point that separates river systemssystems

River System

Tributary

Watershed

Divide

________ – the bends and curves ________ – the bends and curves of a streamof a stream

Meanders

Oxbow lake

deposition

erosion

____________ – deposit formed when a ____________ – deposit formed when a stream spreads out onto a less steep areastream spreads out onto a less steep areaAlluvial Fan

_____ – where a stream empties _____ – where a stream empties into a larger body of waterinto a larger body of water

Delta

GangesRiverDelta

Nile River Delta

Human Impact on StreamsHuman Impact on Streams Flow and courseFlow and course of streams has been of streams has been

changed by human activitieschanged by human activities Dams create Dams create reservoirsreservoirs and are used for and are used for

hydroelectrichydroelectric plants plants Dams and levees can be used to Dams and levees can be used to irrigate farmlandirrigate farmland Dams and levees affect farmland by Dams and levees affect farmland by preventing preventing

sedimentssediments from being deposited on floodplains from being deposited on floodplains Change of course damages or destroys the Change of course damages or destroys the

habitats of organismshabitats of organisms• Areas that were once streambeds become the bottoms of Areas that were once streambeds become the bottoms of

deep lakesdeep lakes

Chapter 10 ReviewChapter 10 Review1.1. To be considered fresh water, water To be considered fresh water, water

must contain salt in a concentrationmust contain salt in a concentrationa.a. More than 30 parts per thousandMore than 30 parts per thousand

b.b. Less than 0.5 parts per millionLess than 0.5 parts per million

c.c. More than 40 parts per millionMore than 40 parts per million

d.d. Less than 0.5 parts per thousandLess than 0.5 parts per thousand

2.2. Brackish water is common inBrackish water is common ina.a. LakesLakes

b.b. OceansOceans

c.c. Coastal marshesCoastal marshes

d.d. aquifersaquifers

3.3. Sunlight reaches the benthic zone inSunlight reaches the benthic zone ina.a. PondsPonds

b.b. Deep lakesDeep lakes

c.c. OceansOceans

d.d. Vents in the ocean floorVents in the ocean floor

4.4. Organisms that live in the benthic zone Organisms that live in the benthic zone of deep lakes are oftenof deep lakes are often

a.a. ProducersProducers

b.b. PlantsPlants

c.c. ScavengersScavengers

d.d. planktonplankton

5.5. A type of standing-water habitat in which A type of standing-water habitat in which the soil is acidic and decay is slow is the soil is acidic and decay is slow is called acalled a

a.a. BogBog

b.b. SwampSwamp

c.c. MarshMarsh

d.d. pondpond

6.6. Phytoplankton arePhytoplankton area.a. ConsumersConsumers

b.b. DecomposersDecomposers

c.c. ProducersProducers

d.d. scavengersscavengers

7.7. Wetlands areWetlands area.a. Easy to defineEasy to define

b.b. Have traditionally been protected by lawsHave traditionally been protected by laws

c.c. Are nonproductive areas that could be better Are nonproductive areas that could be better used for other purposesused for other purposes

d.d. Are important breeding groundsAre important breeding grounds

8.8. Sediments tend to accumulate Sediments tend to accumulate a.a. In slow-moving parts of a streamIn slow-moving parts of a stream

b.b. On the outer edge of a curve in a streamOn the outer edge of a curve in a stream

c.c. In fast-moving parts of a streamIn fast-moving parts of a stream

d.d. Near the beginning of the streamNear the beginning of the stream

9.9. Streams always flowStreams always flowa.a. SouthSouth

b.b. Toward the oceanToward the ocean

c.c. DownhillDownhill

d.d. Toward the poles of EarthToward the poles of Earth

10.10. Levees and dams are Levees and dams are beneficialbeneficial to to farmlands because theyfarmlands because they

a.a. Prevent stream sediments from being Prevent stream sediments from being deposited on the fieldsdeposited on the fields

b.b. Protect the fields from floodsProtect the fields from floods

c.c. Provide a source of irrigationProvide a source of irrigation

d.d. Help refill aquifersHelp refill aquifers

11.11. Levees and dams are Levees and dams are harmful harmful to farm to farm lands because theylands because they

a.a. Prevent stream sediments from being Prevent stream sediments from being deposited on the fieldsdeposited on the fields

b.b. Protect the fields from floodsProtect the fields from floods

c.c. Provide a source of irrigationProvide a source of irrigation

d.d. Help refill aquifersHelp refill aquifers