Chp. 9.3 Notes: Lakes & FreshwaterWetlands
Main idea #1 Fresh water can be found in standing water bodies called lakes or wetlands.
Standing bodies of fresh water Lakes -Formation: Depressions in the ground fill w/ water from rivers, springs, rain, melting snow, & surface runoff.
Wetlands Describe: Land that is saturated with water! Moose love them in Alaska!
Does Shrek live in a marsh or a swamp? What is the difference???
2 Types of Wetlands: 1. Marshes Formation: Sediment accumulates at the bottom of a lake & oxygen runs out due to decomposers using it up. Next, grassy vegetation takes over!
2 Types of Wetlands: 2. Swamps Describe: Swamps are marshes dominated by woody-stem vegetation, such as bushes & trees.
Importance of wetlands Protect land from flooding Recycle nutrients into soil Purify water by removing pollutants Provide shelter for animals Home to strange carnivorous plants & rare reptiles & amphibians
4 Zones of a Lake 1. Littoral zone Describe: Nearshore, shallow zone that is very exposed to sunlight! Life forms: algae, aquatic plants, small crustaceans & amphibians.
2.Limnetic zone Describe: Open water in the middle of a lake. Life forms: Plant & animal plankton & its predators (fish).
3. Profundal Zone Describe: Deeper zone that receives very little light. Life forms: -detritvores, fish. A torchbearer takes the Sochi ‘14 Torch deep into Lake Baikal in Russia. © Sochi ‘14
4. Benthic Zone of a Lake Describe: - Layer of sediment along entire bottom of a lake. Life forms: -detritivores (insects, snails & small crustaceans that eat dead stuff) - “crawly” things.