Aquatic Ecosystems

1. Aquatic Ecosystems Chapter 7

2. Section 7-1 Objectives • 1. Describe the factors that determine where an organism lives in an aquatic ecosystem. • 2. Describe the littoral zone and the benthic zone that make up a lake or pond. • 3. Describe two environmental functions of wetlands. • 4. Describe one threat against river ecosystems.

3. Section 7-1 Vocab • Wetland • Plankton • Nekton • Benthos

4. Section 7-1 Vocab • Littoral zone • Benthic zone • Eutrophication

5. River or lake?

6. Freshwater Ecosystems • Salinity is key • How much salt in water • Controls what lives in these ecosystems

7. Freshwater v. Marine ecosystems • Freshwater • Sluggish waters of lakes and ponds • Moving waters of rivers and streams • Wetlands—land is sometimes under water • Marine • Coastal areas • Marshes, swamps, coral reefs • Oceans

8. What do fish need to survive?

9. Characteristics of Aquatic Ecosystem • Defining characteristics • Amount of • Sunlight • Oxygen • Nutrients

10. Characteristics of Aquatic Ecosystem • Organisms grouped by locations and adaptations • Plankton • Drift only—cannot swim • Phytoplankton—plants • Zooplankton—animals • Nekton • Free-swimming organisms • Benthos • Bottom-dwellers • Decomposers

11. Who’s who? PNB

12. Lakes and Ponds • Part of freshwater ecosystems • Can be… • Natural • Animal-made • Man-made

13. Lake zones • Lake zones are divided horizontally and vertically

14. Lake zones • Littoral zone • Near shore • Diverse living things • Lots of photosynthesis • Benthic zone • Deep in lakes • Not a lot of light for photosynthesis • Decomposers, bacteria, some fish • Less diverse

15. Freshwater Ecosystem Adaptations • Water beetles • Trap air bubbles in “hair” as they dive • Whiskers help cat fish sense food • Amphibians burrow under mud to stay warm

16. Lake nutrients • Too much green—Eutrophic lake • An increase in nutrients… • …leads to an increase in plants and algae… • …leads to an increase in bacterial growth… • …leads to a decrease in dissolved oxygen… • …kills animals. 

17. Eutrophication • Human contribution • Runoff has a high concentration of: • Phosphorus • Nitrogen • Runoff sources • Fertilizers • Detergents • Pesticides

18. Freshwater Wetlands • Areas covered with freshwater for at least part of the year • Two main categories: • Marshes • Swamps • Swamps have trees and other woody plants; marshes don’t

19. Which is it? • Yoda’s refuge, the planet of Dagobah

20. Functions of the wetlands

21. Marshes • Found in SE United States • EX: Florida Everglades • Salt concentration varies • Benthic zone is very nutrient rich

22. Swamps • Flat, poor drained soil • Salt concentration varies • Ideal for frogs and amphibians • Moist

23. Human impact on Swamps and Marshes • Humans did not like these areas initially • Thought to be breeding ground for disease-carrying insects • So, we did the following to wetlands: • Drained them • Filled them • Cleared them for farmland • Florida everglades were originally 8 million acres…now only 2 million acres

25. Rivers • Start from snow melting in mountains • Beginning and end of a river very different • Headwaters—beginning • Cold, lots of dissolved O2, shallow, fast-moving • Open river—end • Warmer, wide, slow, less dissolved O2

26. Adaptations for River Life • Plants and non-moving animals have to hold onto rocks tightly • Moving animals have to be able to swim powerfully against currents

27. Human Impact on Rivers • Remove huge amounts of fresh water for our own use • Dump waste into river • Runoff goes into river • Chemicals go into river • EX Cuyahoga River • On fire • EX Citarum River • Most dirty

28. Pre-viewing Discussion Questions • 1. When did industrialization begin in the United States? • 2. What other important events occurred during this period of time?3. If you led an industrial company around 1900, would you have acted differently? If so, why do you think so?4. How do you think it affected the environment? Give examples. • 5. What is the nature of contemporary industrialization? What impact has it had on nature? • Post-viewing Discussion Questions • 1. Given your understanding of industrialization and its impact, how would you classify, or rank, its value to society? What are its merits and deficits? • 2. How did people, when interacting with the Cuyahoga, “rearrange nature”? Was this rearranging deliberate or unintentional? Were people conscious of their actions’ impact on the environment? Explain. • 3. What environmental hazards continue to exist in the Cuyahoga? How is Northeast Ohio trying to curb these hazards? What additional steps should the region take to improve environmental conditions? • 4. Do you think the region’s residents, business owners, public officials, etc., have learned how to protect the environment, based on their experience with or understanding of the Cuyahoga? Explain. • 5. Think about your immediate natural environment, or larger environmental concerns, such as global warming/climate change. Given America’s knowledge of industrialization’s impact, why do these types of issues continue to exist? What should we be thinking about, in terms of the natural environment, as citizens, business leaders, policy makers, developers, etc.? • Photo by: Univ. of Indiana Library

29. Put it all together • In pairs or groups of 3, you need to make a concept map using the following words. You must make linking phrases to connect these terms. • Freshwater wetlands, lake, littoral zone, freshwater ecosystem, eutrophication, trap and filter pollutants, runoff, benthic, phytoplankton, zooplankton, decomposers

30. Section 7-1 Objectives 1. Describe the factors that determine where an organism lives in an aquatic ecosystem. 2. Describe the littoral zone and the benthic zone that make up a lake or pond. 3. Describe two environmental functions of wetlands. 4. Describe one threat against river ecosystems.

31. Section 7-2 Objectives • 1. Explain why an estuary is a very productive ecosystem. • 2. Compare salt marshes and mangrove swamps. • 3. Describe two threats to coral reefs. • 4. Describe two threats to ocean organisms.

32. Section 7-2 Vocab • Estuary • Salt marsh • Mangrove swamp • Barrier island • Coral reef

33. Coastal Wetlands • Areas near the coast • Covered with salt water either all of the time or part of the time

34. Functions of Coastal Wetlands • Habitat / nesting area for organisms • Absorbs excess rain • Filters pollutants / sediments • Recreation

35. Coastal Wetlands • Form in estuaries—where salt and fresh water mix • Trap nutrients • Very productive • Lots of nutrients • Well protected

36. Plants and Animals of Estuaries • Horseshoe crabs • Lay eggs on beaches in Delaware bay • Migratory birds eat eggs • Human concern: • Harvesting • Medical companies • $60,000/gallon

37. Plants and Animals of Estuaries • Lots of light for photosynthesis • Dolphins, manatees, otters, oysters, barnacles, clams, plankton, fish • Living things have to tolerate different amounts of salt • Due to tides

38. Threats to Estuaries • Sites of landfills • Harbor sites • Boats can damage animals, boat pollution • Runoff pollution • Sewage • Industrial waste • Agricultural Runoff

40. Salt Marshes • Where rivers drop off lots of mud • Support clams, fish, aquatic birds • Nursery for fish, crabs, shrimp • Many of these animals then migrate to the sea

41. Mangrove swamps • Small trees adapted for growing in shallow water • Roots are mostly above ground • Protect coastline from erosion

42. Rocky and sandy Shores • More plants and animals found in rocky shores versus sandy ones • More things to attach or grab on to • Life is adapted to drying out and being exposed to sun at low tide

43. Barrier islands • Can have rocky or sandy shores • Protect mainland • Ocean City New Jersey and other Jersey Shorepoints

45. Coral Reefs • Made out of ANIMALS (coral) • Only found in warm, shallow, clear tropical seas • Inside layers of coral are dead—outmost are alive • Coral is a predator that stings its prey • Related to sea jelly • Provide homes for many animals

46. Reefs in danger • Algae that live within coral can die if.. • Too hot • Too cold • Too muddy • Too polluted • Too high in nutrients

47. Reefs in danger • If algae inside coral die, they lose their color • “bleached” • 50% of all reefs are in danger • Global warming • Oil spills • Pollution • Overfishing • Crown of Thorns predation • Coral cannot repair itself fast enough for the damage being done

48. Oceans • Light only travels down 100m (330ft) into ocean • Most life in more shallow areas • Plankton float on surface, seaweed/algae on rocks

50. Plants and Animals of the Ocean • Phytoplankton must float out in open ocean • Zooplankton follow phytoplankton for food • Both float using oil