freshwater biome
DESCRIPTION
Freshwater Biome. Ch.10. http://people.eku.edu/ritchisong/birdbiogeography1.htm. Aquatic Biomes. Water covers ~ 70% of Earth Aquatic habitat: organisms live in or on water Grouped by depth and salinity of water - PowerPoint PPT PresentationTRANSCRIPT
Freshwater BiomeCh.10
http://people.eku.edu/ritchisong/birdbiogeography1.htm
Aquatic BiomesWater covers ~ 70% of EarthAquatic habitat: organisms live in or on water
Grouped by depth and salinity of water Rainfall and temp. categorize land biomes, but
temp. of waters is fairly consistent and rainfall does not affect the organisms
Campcrescent.com
SalinitySalinity: amount of dissolved salts in the
waterSaltwater: 30 parts/thousand
Oceans and some lakes (Great Salt Lake in Utah) Many saltwater lakes are 40 parts/thousand…..why?
Freshwater: 0.5 parts/thousand Most lakes, ponds, and rivers
SalinityHydrometer
measures density of water by testing buoyancyBuoyancy
amount of mass that can float on the waterIncrease in salt inc. in density inc. in
buoyancy
http://spot.pcc.edu/~lkidoguc/Aquatics/AqEx/Water_Buoyancy.htm
DepthEcosystem depends on amount of sunlight
that reaches the bottom
More sunlight results in a greater number of plants
Plants-basis of food webMore plants leads to more animals
Depth Zones
Depth zonesPlants only grow in photic and shallow parts
of benthic zoneBenthic animals: insect larvae, snails, catfish,
turtles
Alvin, the research submarine, studied cracks in the ocean floorBase of the food web down there was bacteriaBacteria use energy from chemicals that ooze
through those cracks
Questions1. H0w is salinity determined and measured?
2. Suppose a friend wants to set up an aquarium and discovers that saltwater fish are more attractive, but a freshwater tank is easier to maintain. Your friend decides to set up a freshwater aquarium but buys some saltwater fish to place in it. Predict what the result of this decision would be, and why?
2 types of freshwater biomesStanding water
Ponds, lakes, marsh, swamps
Flowing water
http://rrms-biomes.tripod.com/id10.html
Standing Water:
Abiotic Factors Biotic Factors
Lake Deepest standing water, may have aphotic zone
Main producers: floating algae in the photic zone and benthic plants along shoreline
Pond Light reaches benthic zone; fed by rainfall
Producers: plants and algae that grows on bottom
Marsh Very shallow; soil is saturated; often lacks oxygen….Florida Everglades is the largest marsh in US
Plants roots under water, leaves above; mostly grasses; ducks, waterfowl, and benthic animals are common.
Swamp Poor drainage; soil saturated; along flat land; usually along coastline
Dominated by large trees and shrubs; plants adapted to growth in mud & oxygen-poor soil
Bog Inland wetland with little in or outflow; soil acidic; decay is slow; carbon stored in dead plants
Sphagnum moss is dominant organism
Standing water organismsTop level
Plankton Organisms that drift in water About size of a dust particle
Phytoplankton: carries out photosynthesis Main producers in aquatic biomes
Zooplankton: don’t carry out photosynthesis Consumers: feed on phytoplankton
Benthic ZoneHome to scavengers
Feed on remains of other organisms
WetlandsRoots of plants are submerged under water
at least part of the year
Examples: marshes, swamps, bogsSoil is soaked with water and contains little
dissolved oxygen
Important in biosphereFilter chemicals in waterMigratory fowl breed, feed, and rest thereWater sweeps into and refills aquifersProtection against floods
WetlandsCommon grass is papyrusEgyptians first used to make paper around
3000 bcMost common writing surface in eastern
Mediterranean for over 4000 years
Wetlands-human impactMore than half the wetlands in the U.S. have
been destroyedNot attractiveGive off unpleasant odor (methane from
bacteria)Breeding ground for mosquitoes
Usually on coast so can be ideal for development companies
Large so are used at times as landfillsClean water act: prohibits the filling of
wetlandsIn US only 8% wetlands are federally protected
Florida EvergladesHome to a large number of organisms
Adapted to cycles of growth, drought, and fireWater was drained from the everglades to create
farmland1947: Everglades National Park
Created to save everglades, but needed water1967 a canal was dug to get water to parkWater came too fast in too narrow of a stream
Caused flooding of the area and organisms homes 93% decrease of bird population and decline of
alligators1983: Save our Everglades campaign
Designed to clean up contamination from farms and restore a natural water flow100,000 acres of wetland has been restored
Questions1. What is the difference between the role of
phytoplankton and that of zooplankton?
2. The number of migratory birds in the tundra during the summer has been declining. How might changes that have taken place in the wetlands have contributed to this decline?
Flowing WaterRivers, streams, creeks, brooksScientists refer to all above ground bodies of
water as Streams.
Flowing Water OrganismsOrganisms that live in flowing water habitats are
adapted to the rate of water movement.Adaptations:
Hooks (grab plants)Suckers (attach/anchor to rocks)Salmon and trout are well adapted to flowing water
Grow in freshwater but spend adult life in ocean Breeding season they swim upstream to same spot they
hatched Find the “spot” by smelling the small amt of chemicals
in H2O
FlowMost streams begin at high altitude
From runoff of melting snowGravity brings downhillStarts Inland usually then goes out to ocean
Where streams slow down is where a majority of sediment accumulatesSediment provides a place for plant roots to
growColder water contains more dissolved oxygen
and therefore supports more animal lifeWhy pop loses its fizz when room temperature
FlowErosion along the fast-flowing outer edge and
sedimentation along the slow-flowing inner edge result in the winding, or meandering, of a stream
The older a stream is the more curvy it getsHuman activity
Streams have been dammed to make resevoirsDams, dikes, and irrigation canals used to
change stream coursesDams also used to control flooding
Questions1. Why are there fewer organisms in the
headwater of a stream than further downstream?
2. the headwaters of a stream often contain more dissolved oxygen than the water hundreds of kilometers downstream. Why is this true?