AQUATIC ECOSYSTEMS Determined by the salinity of water 2 types: Freshwater & Marine.
AQUATIC ECOSYSTEMS Determined by the salinity of water Determined by the salinity of water – 2...
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AQUATIC ECOSYSTEMS • Determined by the salinity of water –2 types: •Freshwater : lakes, ponds, rivers, streams, wetlands •Marine: coastal marshes & swamps, coral reefs, oceans
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Transcript of AQUATIC ECOSYSTEMS Determined by the salinity of water Determined by the salinity of water – 2...
AQUATIC ECOSYSTEMS
• Determined by the salinity of water–2 types:• Freshwater : lakes, ponds, rivers,
streams, wetlands
•Marine: coastal marshes & swamps, coral reefs, oceans
CHARACTERISTICS
• TEMPERATURE• SUNLIGHT*• OXYGEN• NUTRIENTS
Determines which organisms live where
*Photosynthetic organisms live near the surface
Three types of organisms:based on location & adaptations
• Plankton– Phytonplankton– zooplankton
• Nekton
• Benthos
Plankton – microscopic drifters
Phytoplankton: photosynthethicAlgae (base of food chain)
Zooplankton: heterotrophic microscopic organisms – jellyfish
Nekton – free-swimming
Benthos – bottom dwelling
Decomposers
7-1 Freshwater Ecosystems
• These include rivers, streams, lakes, and ponds.
• Rivers and streams have moving water. The water may be moving fast or slow.
• Lake are usually larger and deeper than ponds.• Just like in the oceans, plants and animals live
in the shallow (less deep) parts. The sun shines more in the shallow parts.
Lakes & Ponds
• Littoral zone: near shore– Nutrient rich– Diverse life– Plants rooted in mud, stems above water
Littoral zone
Lakes & Ponds
• Open water:– Further from shore– No rooted plants– Phytoplankton starts
food chain
Lakes & Ponds
• Deep Water:– No light– Bacteria &
decomposers live on dead things that drift down
– Fish adapted to cool water
Lakes & Ponds
• Benthic Zone:– Bottom– Decomposers, insect larva, clams
How nutrients affect lakes• Eutrophication= an
increase in the amount of nutrients in an aquatic ecosystem.
• Plants & algae grow• Bacteria feeding on
decaying plants grow• Bacteria use oxygen in
water• Reduced oxygen levels
kills fish • Run-off increase nutrients
Freshwater WetlandsSwamps – woody plantsPoorly drained land,
Marshes – non-woody plants (cattails, grasses)
Function of Wetlands
• Trap & filter sediments, nutrients, pollutants• Reduce flooding• Buffer shoreline against erosion• Spawning grounds & habitat for fish &
shellfish• Provide habitat for rare, threatened,
endangered species• Recreation
Human Impact
• Considered wasteland & breeders of disease carrying insects. Drained, cleared & developed.
• Now we recognize importance as water purifiers & flood prevention.
% of Wetlands lost . 22 states have lost 50% of wetlands7 have lost 80% (Indiana, Ill, Miss, Ky, Iowa, Calif, Ohio
Rivers
• Headwaters – origin may be snowmelt or rain• Full of oxygen, runs swiftly through shallow
riverbed• Becomes wider, warmer, slower, contains
more vegetation & less oxygen• Communities & industries affect health of
rivers.
Flint River
Lake Lanier
Atlanta’s drinking water
Characteristics of Aquatic Ecosystems
