Aquatic Biodiversity

1. Aquatic Biodiversity Chapter 7

2. Coral Reefs • Structure that is formed by coral polyps (small invertebrates that live in colonies). • Typically found in warm coastal waters of the tropics and subtropics. • Coral polyps form a hard, stony, branching structure made of limestone. • New polyps attach to old coral and gradually build the reef.

3. Coral Reefs Climate • Usually found near land in shallow, warm salt water. • Lots of light • Tropical temperatures, averaging 70°-85° F

4. Importance of Coral Reefs • High biodiversity- considered the most diverse and productive • Grow very slowly • Complex relationships that exist between many organisms.

5. Example of Food Chain

6. Damage to Coral Reefs • Very sensitive to environmental changes. • Natural disturbances: hurricanes or typhoons, and predation by a large starfish-Acanthaster • Anthropogenic disturbances (human)- sediment run off, pollution, reef fishing, bleaching… • 300+ reefs are protected as reserves or parks.

7. Chapter Overview Questions • What are the basic types of aquatic life zones? • what factors influence the kinds of life they contain? • What are the major types of saltwater life zones? • how do human activities affect them? • What are the major types of freshwater life zones? • how do human activities affect them? • Aquatic Biodiversity

8. Aquatic Life Zones (Aquatic Biomes) • Characterized by amount of NaCl, etc dissolved in the water. • Saltwater (marine) and freshwater cover ~ 71% of the earth’s surface. • Food chains and webs are more complex and longer than terrestrial ones.

9. Distribution of Organisms • Based upon salinity – • 2 groups: • Saltwater/Marine • Estuaries, coastlines, coral reefs, mangrove swamps, oceans • Freshwater

10. Chesapeake Bay: America’s Largest Estuary! • About half of the Bay’s water volume comes from salt water from the Atlantic Ocean. • The other half drains into the Bay from its enormous 64,000-square-mile watershed. • Because of this mix of fresh and salt water, the Bay’s salinity gradually increases as you move from north to south. • Video: http://www.youtube.com/watch?feature=player_embedded&v=jeyOA0mwBhc#!

11. Organisms & Aquatic Life Zones • Plankton: free floating - Phytoplankton: ex: algae - Zooplankton: animal plankton. ex: protozoans (amoeba, paramecia) -Ultraplankton: autotrophic bacteria (70% GPP near ocean’s surface!) 2. Nekton: free-swimming. ex: fish, turtles, whales 3. Benthos: bottom dwellers. Ex: barnacles, lobsters 4. Decomposers: ex: bacteria, water molds

12. Limiting Factors • Life (numbers and diversity) in the surface, middle, and bottom layers are determined by: • Temperature • Sunlight penetration (for photosynthesis):upper layers or Euphotic zone • Amount of dissolved oxygen:  at lower levels • Nutrient availability (CO2, NO3-, PO43-): • shallow waters = lots of nutrients • ocean-  nutrients, areas with upwelling have  nutrients.

13. Euphotic Zone – Upper Layer of Deep Aquatic Systems Excessive Algal Growth may cause cloudiness a.k.a “Turbidity” - Eutrophication!

14. Marine Ecosystems • Scientists estimate that marine systems provide $21 trillion in goods and services per year – 70% more than terrestrial ecosystems.

15. NATURAL CAPITAL Marine Ecosystems Ecological Services Economic Services Climate moderation Food CO2 absorption Animal and pet feed Nutrient cycling Pharmaceuticals Waste treatment Harbors and transportation routes Reduced storm impact (mangroves, barrier islands, coastal wetlands) Coastal habitats for humans Recreation Habitats and nursery areas Employment Oil and natural gas Genetic resources and biodiversity Minerals Scientific information Building materials Fig. 8-4, p. 165

16. Oceans • Largest of all ecosystems (71% of Earth’s Surface!) • High biodiversity • 2 zones: 1. Coastal- warm and nutrient rich area 90% of all marine species!  NPP 2. Open sea- cooler and less species

17. The Coastal Zone Extends to the shallow edge of the continental shelf

18. The Coastal Zone • 10% of the Ocean is Coastal Zone, yet it contains 90% of all marine species! • High NPP from • Lotsa Light! • Nutrient runoff from land and wind

19. Estuaries • Enclosed body of water formed where seawater mixes with freshwater from rivers & streams. • Called “ Marine nurseries”- habitats for many juvenile fish species. • Temperature and salinity vary due to the daily tides and seasonal flow of freshwater • Estuaries and coastal wetlands include inlets, mangrove forest swamps, & salt marshes

20. Estuaries Con’t • Extremely fertile due to constant movement of water. • Stressful conditions and abundant nutrients result in low species diversity, but great abundance of the species present. • Helpful in filtering pollutants and sediments. • Humans are constantly destroying and degrading these ecosytems.

21. Estuaries and coastal marshes provide ecological and economic services. • Filter toxic pollutants, excess plant nutrients, sediments, and other pollutants. • Reduce storm damage by absorbing waves and storing excess water produced by storms and tsunamis. • Provide food, habitats and nursery sites for many aquatic species.

22. Herring gulls Peregrine falcon Snowy Egret Cordgrass Short-billed Dowitcher Marsh Periwinkle Phytoplankton Smelt Zooplankton and small crustaceans Soft-shelled clam Clamworm Bacteria Producer to primary consumer Primary to secondary consumer Secondary to higher-level consumer All consumers and producers to decomposers

23. Mangrove Forests • Are found along about 70% of gently sloping sandy and silty coastlines in tropical and subtropical regions.

24. Mangrove Plant Adaptations • Low Oxygen/High Salinity: • These roots raise above the water level and acquire air through pneumatophores • Roots may reach a height of 30 cm to 3 meters. • Read more at:http://scienceray.com/biology/adaptations-of-the-mangrove-forests-a-scientific-review/#ixzz2Ipa3KIZe

25. Ecological Services of Mangroves • Nutrient rich silt and constant water movement = stimulates producers! • Filter toxic pollutants/excess sedimentation • Food/Habitat, nursery for aquatic species • Reduce storm damage • Store extra water and absorb waves

26. Intertidal Zone – Where the ocean meets the land • Sometimes submerged and other times exposed. • Communities are constantly changing in this area. • Rocky shores- areas pounded by waves, varieties of algae, snails, crabs, etc. • Sandy shores- no plants or algae, but insects, shorebirds, crabs, and worms found

28. Barrier Islands • Long, narrow, offshore deposits of sand or sediments that parallel the coast line. • Aid in protecting mainland, estuaries, & coastal wetlands. • Found along eastern coasts and Gulf of Mexico • Lots of development

29. Primary Dune Secondary Dune Bay or Lagoon Ocean Beach Trough Back Dune No direct passage or building No direct passage or building Limited recreation and walkways Most suitable for development Intensive recreation, no building Intensive recreation Grasses or shrubs Bay shore No filling Taller shrubs Taller shrubs and trees

30. Damage to barrier islands A single home is left standing among debris from Hurricane Ike September 14, 2008 in Gilchrist, Texas. Floodwaters from Hurricane Ike were reportedly as high as eight feet in some areas causing widespread damage across the coast of Texas. (David J. Phillip-Pool/Getty Images) Damage from Hurricane Ike

31. Open Ocean and Ocean Floor • Open Ocean - sharp increase in water depth at the edge of the continental shelf • Brightly lit surface layer • Dimly lit middle layer • Dark bottom zone

32. Open Ocean Zones • Euphotic – Lighted upper zone • Photosynthesis by phtoplankton • Low nutrients without upwellings • High DO (mg/L) • Awesome large predatory fish!

33. Open Ocean Zones • Bathayal Zone – Dimly lit middle zone • Little to no PS • Zooplankton and smaller fish

34. Open Ocean Zones • Abyssal Zone – dark and cold deepest zone • Little DO • Enough nutrients on the ocean floor to support 98% of species living there! Deposit feeders extract nutrients from ocean mud! Filter feeders

35. Effects of Human Activities on Marine Systems: Red Alert • Human activities are destroying or degrading many ecological and economic services provided by the world’s coastal areas.

36. Human Activities Are Disrupting and Degrading Marine Systems • Major threats to marine systems • Coastal development • Overfishing • Runoff of nonpoint source pollution • Point source pollution • Habitat destruction • Introduction of invasive species • Climate change from human activities • Pollution of coastal wetlands and estuaries

37. Major Human Impacts on Coral Reefs • http://www.youtube.com/watch?v=A2KmFJu1yPA

38. Case Study: The Chesapeake Bay – An Estuary in Trouble! • http://www.youtube.com/watch?v=_H0nrhM21cw

39. Natural Capital Freshwater Systems Ecological Services Economic Services Natural Capital Climate moderation Nutrient cycling Waste treatment Flood control Groundwater recharge Habitats for many species Genetic resources and biodiversity Scientific information Food Drinking water Irrigation water Hydroelectricity Transportation corridors Recreation Employment

40. Freshwater Life Zones • Cover less than 1% of earth’s surface. • Low salt concentration- < 1% • Types: Flowing (lotic) - streams, and rivers Standing (lentic) - ponds, lakes, inland wetlands

41. Kettle Lake

42. Lakes and Ponds Zones • divided into four different “zones” determined by depth and distance from the shoreline: 1. Littoral zone- top layer, shallow/near shore,  biodiversity. aquatic plants, grazing snails, clams, insects, crustaceans, fishes, and amphibians 2. Limnetic zone-sunlit water surface layer, main photosynthetic layer. plankton, fishes 3. Profundal zone-cool and dark layer,  O2 4. Benthic zone-bottom layer, decomposers and detritivores.

43. Lakes: Water-Filled Depressions • During summer and winter in deep temperate zone lakes the become stratified into temperature layers and will overturn. • This equalizes the temperature at all depths. • Oxygen is brought from the surface to the lake bottom and nutrients from the bottom are brought to the top. • What causes this overturning?

46. Oligotrophic Newly formed Poorly nourished Little sediment Deep water Clear water color Low net primary prod. Trout, smallmouth bass Eutrophic Excess supply of nutrients (Phosphates & nitrates) Shallow water Murky water color High net prod. Lots of plants, fish, plankton Lake ClassificationClassified by: nutrient content and primary productivity MESOTROPHIC LAKES- intermediate between oligotrophic and eutrophic

47. Effects of Plant Nutrients on Lakes:Too Much of a Good Thing • Plant nutrients from a lake’s environment affect the types and numbers of organisms it can support.

48. Effects of Plant Nutrients on Lakes:Too Much of a Good Thing • Cultural eutrophication: • Human inputs of nutrients from the atmosphere and urban and agricultural areas can accelerate the eutrophication process.

49. Terminology • Surface water- precipitation that does not sink into ground or evaporate • Runoff- surface water that flows into streams • Watershed (Drainage basin)- The region draining into a river, river system, or other body of water.

50. Characteristics of Rivers and Streams • bodies of flowing water moving in one direction • found everywhere—they get their start at headwaters, which may be springs, snowmelt or even lakes • travel all the way to their mouths, usually another water channel orthe ocean