Ecology: Chapter 10

 Not grouped geographically the way terrestrial biomes are  Difficult to be shown on a map  Scattered  Two types: Freshwater and Saltwater  Two most important determining factors: amount of dissolved salts and depth of water  Other factors that determine organisms: rate of flow and amount of dissolved oxygen

 All bodies of water contain some salts and minerals  Salinity is measured in parts per 1000 (units of salts per 1000 units of water) ◦ Ocean water: 30 parts per 1,000 ◦ Fresh water: 0.5 parts per 1,000 or less  Brackish water: water that is more saline than fresh water, but less saline than ocean water ◦ Ex: river delta, coastal marshes (where freshwater meets ocean waters)

Great Salt Lake in Utah Mono Lake in California

Depth zonesPHOTIC DEPTH DEPENDS ON CLEARNESS OF WATER UP TO 200M DEEPIN OPEN OCEAN APHOTICSUNLIGHT NEVER REACHES ONLY IN OCEANS AND VERY DEEP LAKES BENTHIC SUPPORTSMICROSCOPIC DECOMPOSERS AND SCAVENGERS COMMON FRESHWATER ANIMALS : INSECT LARVAE, SNAILS, CATFISH, TURTLES MAY RECEIVE SUNLIGHT IN SHALLOW WATERS

Freshwater biomes Standing Water lakes & pondswetlands Flowing water rivers, streams, creeks & brooks

ABIOTIC FACTORSBIOTIC FACTORS LAKE -Deepest type of standing water -may have aphotic zone -may be fed by underground aquifers -producers: algae in photic zone & benthic plants along shoreline -complex food webs POND -Benthic zone receives light -fed by rainfall -seasonal -producers: plant & algae (grows on bottom) -food web not as complex as lakes MARSH -shallow water -soil is saturated -water lacks O2 -saltwater, freshwater, brackish, often tidal Ex: Florida Everglades -plants have roots under water -leaves are above water (emergent) -grasses, cattails, rushes -ducks, waterfowl, benthic animals SWAMP -land soaked w/ water (poor drainage) -streambeds or flat land -dominated by large trees & shrubs -plants adapted to grow in muddy, O2 poor soil Ex: Cypress trees-south US; Willow & dogwood-north US BOG-inland wetland w/ little inflow or outflow -acidic soil -slow decay -carbon stored in dead plants -sphagnum moss is dominant organism -partly decayed moss accumulates as peat

 Plankton: general term for organisms that drift in water ◦ size of dust particles  Phytoplankton ◦ Plankton that carries out photosynthesis ◦ Main producers in most aquatic biomes  Zooplankton ◦ Do NOT carry out photosynthesis ◦ Consumers ◦ Feed on phytoplankton

 Ecosystems in which the roots of plants are submerged under water at least part of the year  Act as filters, detoxifying chemicals in water that pass through them  can be used as treatment systems for waste water  Breeding, feeding waterfowl (geese & ducks)  Act as flood protection regions (wetlands along the banks)  Swamp Lands Act 1849: encouraged the filling or draining of wetlands  Clean Water Act: stopped the filling of wetlands, only 8% of wetlands in US are protected by govt

 Ex: rivers, streams, brooks, creeks  Stream Organisms ◦ Organism adapt to rate of water movement ◦ Ex: salmon  Stream Flow ◦ begin at high altitude ◦ streams flow downhill=gravity ◦ Flow towards the ocean ◦ place where streams begin=source, or head, of the stream ◦ Water near the source is called headwater  Sediments: small particles that settle to the bottom of a body of water

 Sedimentation  Erosion  As stream curves (a.k.a.meanders) fig ◦ Water flowing on the inside of curve slows down ◦ Water flowing on the outside of curve speeds up ◦ Sediments build up along inner edge-slowed flow ◦ Erosion increases along the outer edge-rapid flow Cause stream to alter its course