Unit 6: Terrestrial & Aqua2c Diversity Chapter 6 & 7. Earth has three major climate zones: Tropical, Temperate, Polar.

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1 Unit 6: Terrestrial & Aqua2c Diversity Chapter 6 & 7 Earth has three major climate zones: Tropical, Temperate, Polar Chapters 6 & 7

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3 Factors affec1ng climate: 1. Uneven hea1ng of the earth s surface by the sun Sun rays hit equator poles sunlight is least direct High solar radia1on à increased evapora1on & precipita1on 2. Tilt in Earth s axis Leads to seasonal changes in temp & precipita1on 3. Rota1on of the earth on its axis B/c of rota1on, winds are deflected east/west, creates global paqerns of prevailing winds that distribute heat & moisture 4. Proper1es of air, water, & land: Hot air tends to rise, cool, & release moisture as precipita2on Cool air tends to sink, get warmer, & lose its moisture by evapora2on, These two proper1es cause convec-on cells to circulate air, heat & moisture

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6 5. Ocean currents redistribute heat & influence air circula1on; created by: Wind blowing over oceans Differences in water density Also mix waters & distribute nutrients

7 Winds blowing along western coasts push surface water away from land à causes upwelling: deep, cold, nutrient-rich water rises Nutrients support large pops of phytoplankton à zooplankton à fish, birds, mammals

8 Coriolis Effect: In physics, the Coriolis effect is a deflec1on of moving objects when the mo1on is described rela1ve to a rota1ng reference frame The Coriolis effect makes storms swirl clockwise in the Southern hemisphere and counterclockwise in the Northern Hemisphere hqps:// watch?v=i2mec3vgeai

9 Important Clima1c Events: El Niňo Southern Oscilla-on (ENSO) When prevailing tropical winds blowing westward weaken or reverse Warms surface water along South & North American coasts à suppresses normal upwellings of cold, nutrient-rich water Causes decline in fish species Can cause extreme weather in Pacific & Indian Oceans La Niňa Reverse of El Niňo Results in more Atlan1c hurricanes, colder winters in Canada & NE U.S., and warmer/drier winters in southern U.S.

10 6. Temperature is also affected by greenhouse effect Greenhouse gases warm lower atmosphere: H 2 O CO 2 CH 4 (methane) N 2 O (nitrous oxide) Gases reflect infrared radia1on back to earth s lower atmosphere

11 7. Topography (earth s surface features) can affect climate Ex: Rain Shadow Effect Ex: Ci1es create microclimates: have more pollu1on, higher temps, & lower wind speeds

12 Terrestrial Diversity Biomes vary with La1tude: north & south of equator Al1tude: distance from sea level

13 Desert Biomes Area where evapora1on > precipita1on Low precipita1on Found mostly in tropical & subtropical regions 3 types Tropical desert: hot & dry most of year Few plants Ex: Africa s Sahara Temperate desert: Day1me temps high in summer, low in winter Shrubs, cac1; rep1les, birds Ex: North America s Mojave Cold desert: Winters are quite cold, summers are warm/hot Ex: China s Gobi

14 Terrestrial Diversity Desert Climate Graphs:

15 Desert Adapta1ons: Succulent plants save water by having no leaves, store water in their flesh, & open stomata at night Evergreen plants have waxcoated leaves to save water Many animals are nocturnal Insects & rep1les have thick scales to minimize evapora1on

16 TED Talks: Ecology from the Air: hqp:// greg_asner_ecology_from_the_air hqp:// hqp://

17 Grasslands Biomes Enough precip. for grasses, not enough for shrubs or trees Occur in interiors of con1nents Persist b/c of: 1. Seasonal drought 2. Grazing by herbivores 3. Occasional fires

18 Grasslands 3 types: Tropical grassland: Savanna Warm most of year; alterna1ng dry & wet seasons Found in Africa, South America, Australia; Acacia trees; many herbivores like elephants, zebra, giraffes, gazelles; Animals have mass migra1ons to find water; plants adapted to drought, Threatened by grazing of caqle (fecal pavement) Temperate grassland: Prairie Day1me temps warm in summer, low in winter Found in North America, South America, Asia Has deep, fer1le, alkaline topsoil Grasses have thick root network Animals include prairie dogs, bison, coyote, eagles Cold grassland: Tundra Most of year is cold Has Permafrost = frozen underground soil Hares, voles, lynx, weasel, snowy owl, fox, bears (thick fur) Canada, Russia There s also the Alpine tundra high mountains Threatened by oil drilling & mining

19 Terrestrial Diversity Grassland Climate Graphs

20 Forest Biomes: 4 types Tropical Rain forest Near equator Year-round warm temps & high precip. (80F, in per year) Dominated by broadleaf evergreen plants à create canopy High NPP & biodiversity: Parrots, frogs, insects, monkeys, snakes, jaguar, etc. Nutrient-poor, acidic soil Temperate Rain forest NW America Moderate temps & high precip. Dominated by coniferous evergreen trees (spruce, fir, redwoods) Lots of moss Rela1vely lower biodiversity due to limited light Major source for 1mber Animals: elk, weasels, owls, bear, cougar, salmon, etc.

21 Temperate deciduous forest US, Europe Warm summers, cool winters Dominated by broadleaf deciduous trees (oak, maple, hickory) à dormant in winter, grow leaves back each spring Lots of birds, rodents, insect, some larger mammals (deer, skunks, foxes, bears) Taiga/ Boreal forest/coniferous South of arc1c tundra in N. America, Europe, Asia Warm summers, cool winters Dominated by coniferous evergreen trees (spruce, pine, fir, cedar) Needles prevent water loss Needles make soil acidic Slow decomp Animals: bears, wolves, lynx, caribou, chipmunks, weasels, etc. Hibernate

22 Terrestrial Diversity Forest Climate Graphs

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24 Aqua1c Life Zones Types of Aqua1c Organisms: Plankton: free floa1ng organisms; 3 types Phytoplankton Includes: Algae (diatoms, dinoflagellates) and cyanobacteria Are Primary producers Zooplankton Single-celled to large invertebrates like jellyfish Are Primary and secondary consumers Ultraplankton Tiny photosynthe1c bacteria

25 Aqua1c Life Zones Types of Aqua1c Organisms cont.: Nekton Strong swimmers: fish, turtles, whales Benthos BoQom dwellers: oysters, sea stars, clams, lobsters, crabs, worms Decomposers: mostly bacteria

26 Aqua1c Life Zones Key factors in distribu1on of organisms: 1. Temperature: Decreases w/ depth 2. Availability of light for photosynthesis Confined to Eupho2c (pho1c) zones Decreases w/ depth 3. Dissolved oxygen content Decreases with depth 4. Availability of nutrients (CO 2, NO 3-, PO 4 3- ) CO 2 increases with depth 5. Turbidity: degree of cloudiness in water Inhibits photosynthesis

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28 Aqua1c Life Zones Marine Life Zones: 3 major life zones

29 Marine Life Zones: 3 major zones 1. Inter2dal & Neri2c/ Coastal Area of seafloor between high 1de & low 1de over con-nental shelf Alterna1vely dry & wet during day Organisms adapted to harsh environment: Changes in salinity, temp. & water level Plants & Animals of the Inter1dal Zone Highest up: Mollusks, barnacles, algae Middle: algae, sponges, sea anemones, mollusks, crustaceans, echinoderms (spiny skin), small fishes Lowest: Seaweeds, worms & fishes

30 Types of Inter1dal Zones 1. Estuaries: where rivers meet the sea 2. Coastal Wetlands: land covered with water all or part of year: Inlets, bays, sounds, mangrove forests, salt marshes Important b/c: Serve as breeding grounds & nurseries Economically valuable Decrease impacts of flooding

31 2. Coastal (Neri1c) Zone From shore to edge of con1nental shelf Warm, nutrient rich, shallow High NPP from sunlight and nutrients Contains 90% of all marine species & most fisheries Coastal Zones: ecological and economic services Maintain water quality by filtering: Toxic pollutants Excess plant nutrients Sediments Provide food, 1mber, fuelwood, habitats Reduce storm damage and erosion

32 Types of Coastal (Neri1c) Zones: 1. Coral Reefs Tiny animals (coral polyps) secret calcium carbonate shells, which become coral reefs Polyps and zooxanthellae algae have mutualis1c rela1onship: Algae provide oxygen from photosynthesis & chemical energy; Coral polyps provide home Ecosystem Services: Marine equivalent of tropical rain forests Provides habitat for one-fourth of all marine species Moderates climate b/c takes up CO2 Economic/ Social Services: Food Potential medicine Employment & Recreation

33 Coastal Zone: Coral Reefs Causes of Degrada1on: (Human-caused) Warmer ocean temperatures and Increasing ocean acidity leading to coral bleaching: kills algae and thus the polyps Coastal development Pollu1on Overfishing/ trawling Boat/anchor damage

34 3. Open Ocean: Three ver1cal zones: 1. Eupho2c zone: lit upper zone Phytoplankton perform photosynthesis Nutrient levels low & d-oxygen levels high Have fast swimming, predatory fish (swordfish, sharks, tuna) 2. Bathyal zone Dimly lit, few producers Have zooplankton and smaller fishes 3. Abyssal zone Dark & cold No photosynthesis, liqle d- oxygen High nutrients Have deposit & filter feeders (eat marine snow), slow fish

35 Marine Life Zones: 3 major zones 3. Benthic Zone: = The Ocean Floor Underlies all the other zones Communi1es consist of Bacteria Fungi Seaweed (algae) Invertebrates (sponges, echinoderms, mollusks) Fish

36 Aqua1c Life Zones Deep-Sea Hydrothermal Vents Dark, HOT!, Oxygen-deficient environment Producers are chemoautotrophic bacteria (use chemosynthesis instead of photosynthesis) Consumers eat bacteria or other consumers: tube worms, shrimp, crabs, mussels, worms, etc.

37 Major threats to marine systems: Coastal development Habitat destruc1on Overfishing Use of fishing trawlers Pollu1on Introduc1on of invasive species Climate change Ocean acidifica1on

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39 Freshwater Life Zones: includes: Len2c (standing) bodies of freshwater: Lakes Ponds Inland wetlands Lo2c (flowing) systems of freshwater: Streams Rivers

40 Lakes: bodies of standing fresh water formed when precipita1on, runoff, or groundwater seepage fill depressions in earth s surface

41 4 Lake Zones: 1. LiToral zone Near shore with rooted plants High biodiversity: turtles, frogs, crayfish, some fish 2. Limne2c zone Open, sunlight area away from shore Main photosynthe1c zone Some larger fish 3. Profundal zone Deep water too dark for photosynthesis Some fish 4. Benthic zone Decomposers & detritus feeders Some fish Nourished primarily by dead maqer

42 Aqua1c Life Zones Lake Types Based on Nutrient Levels: Oligotrophic lakes Low nutrients and low NPP Very clear water Eutrophic lakes High nutrients and high NPP Murky water with high turbidity Cultural (ar2fical) eutrophica2on: input of excess nutrients (fer1lizers) causing excess algal growth

43 Oligotrophic lake

44 Eutrophic lake

45 Freshwater Degrada1on: Dams destroy habitat Flood control levees and dikes along rivers alter flow & destroy habitat Pollutants from ci1es and farms on streams, rivers, and lakes Draining wetlands for agriculture & development