1. Freshwater Water that contains relatively little dissolved salt

2. Freshwater ecosystems include: Standing waters of lakes and ponds moving waters of rivers and streams areas where land and water come together known as the wetlands

3. Plant and animal life found in a freshwater ecosystem depends on the depth of the water how fast the water moves the amount of mineral nutrients, sunlight, and oxygen.

4. A pond or lake ecosystem is structured according to how much light is available –The shallow-water area near the shores of lakes and ponds where sunlight reaches the bottom is called the littoral zone It is a nutrient rich area

5. farther out from the shore: open waters that get enough sunlight for photosynthesis is dominated by phytoplankton (tiny plants) and zooplankton (tiny animals) areas that are too deep for photosynthesis to occur: dead plants and animals drift down from above and are decomposed by bacteria, and a few fish adapted for cooler, darker water also live there. Benthic zone – The body of water which is inhabited by decomposers, insect larvae, and clams.

6. Eutropic lakes a lake with a large amount of plant nutrients As the amount of plants and algae grows: the number of bacteria feeding on the decaying organisms also grow. These bacteria use up the oxygen dissolved in the lake’s water. eventually, the diversity of species declines

7. Lakes naturally become eurtophic over a long period of time However, the process of eutrophication can be accelerated by runoff from sewage, fertilizers, and animal wastes.

8. PLANT AND ANIMAL ADAPTATIONS Along the shore: cattails reeds they are rooted in the bottom mud. their upper leaves and stems emerge above the water

10. in deeper water pond lilies – a floating plant waterbettles trap air in the hairs under their bodies because they cannot get air directly from the water.

12. dark lake bottom: catfish – whiskers help catfish sense food

13. adaptations to temperature: lake trout need cold water bass prefer warmer waters regions where lakes partially freeze in winter, amphibians burrow into the littoral mud.

14. WETLANDS – areas of land that are covered with water for at least part of the year.

15. 2 types of freshwater wetlands and 1 type of saltwater wetland marshes – land covered with water; contain non- woody plants swamps – land covered with water; contain woody plants or shrubs estuaries (we will talk about later)

18. functions of wetlands: fish use the wetlands for feeding and spawning they provide a home for native and migratory wildlife, including endangered and threatened species wetland vegetation traps carbon that would otherwise be released as carbon dioxide (which is harmful to the atmosphere remove pollutants from the water, control flooding by absorbing extra water when rivers overflow, produce many commercially important products such as cranberries, blueberries, and peat moss.

19. Marshes plants include reeds, rushes and cattails they are rooted in the bottom sediments, but their leave are above water. The benthic zone is rich, containing plants and numerous decomposers and scavengers.

20. waterfowl: grebes and ducks have beaks adapted for eating marsh vegetation. herons have spear like beaks that is used to grasp small fish and frogs.

21. marshes attract nesting birds such as blackbirds marshes are characterized by its salinity and organisms are adapted to live within the ecosystem’s range of salinity

22. Brackish marshes have slightly saline water tidal marshes – contain saltier water

23. the everglades in Florida is the largest freshwater marsh in the united states

24. swamps occur on flat, poorly drained land, often near streams they are dominated by shrubs or water- tolerant trees such as red maple, cedar, oak, or cypress

25. mangrove swamps occur in warm climates near the ocean, so their water is saline

26. ideal habitat for many amphibians such as green frogs and salamanders and birds such as wood ducks that nest in hollow swamp trees.

27. threats to wetlands used to be considered wastelands… they were drained and cleared for farms or development. their importance is now recognized: purifiers of wastewater and absorbers of otherwise hazardous flood waters the federal government and most states now prohibit destruction of some wetlands

28. RIVERS most originate from snowmelt in mountains at its headwaters it is usually cold and highly oxygenated, running swiftly through shallow riverbeds rivers then broaden, become warmer, lose oxygen, and flow more slowly. runoff provides rivers with nutrients, which settle to the bottom as sediment. therefore the surrounding land affects the growth and health of organisms in rivers.

29. plant and animal adaptations near the headwaters, mosses have root like structures called rhizoids that they use to anchor themselves to rocks. mayfly nymphs use hooks on their legs to cling to any stable surface

30. frogs use the suction cups on their toes to maintain stability trout and minnows thrive in the cold, oxygen-rich headwater trout have streamlined bodies that present less resistance to the strong current and they’re powerful swimmers.

31. further downstream Catfish and carp prefer the warmer, calmer waters. carp are adapted to gliding over the river bottom but not to swimming against the current. water crowfoot set roots down into the sediment fig 4-45: shows how the arrowhead plant’s leaf shape varies according to the strength of a river’s current.

32. In fast waters the leaves are submerged In slower waters the leaves are floating In calm waters the leaves are aerial

33. Threats To Rivers: Industries use river water in manufacturing processes and as a receptacle for waste. People use rivers to “take away” their sewage and garbage. pesticides and other poisons coat riverbeds with toxic sediments Dam building alters river flow and may destroy fish habitat.