Transcript Chapter 5
Chapter 5 Climate and Terrestrial Biodiversity Chapter Overview Questions What factors the earth’s climate? How does climate determine where the earth’s major biome’s are found? What are the major types of desert biomes? What are the major types of grassland biomes? Chapter Overview Questions (cont’d) What are the major types of forest and mountain biomes? How have human activities affected the world’s desert, grassland, forest, and mountain biomes? Updates Online The latest references for topics covered in this section can be found at the book companion website. Log in to the book’s e-resources page at www.thomsonedu.com to access InfoTrac articles. InfoTrac: Of Chicks and Frogs. Steven Pinker. Forbes, August 14, 2006 v178 i3 p40. InfoTrac: Nice Rats, Nasty Rats: Maybe It's All In the Genes. Nicholas Wade. The New York Times, July 25, 2006 pF1(L). InfoTrac: Ancient shrub unlocks a clue to Darwin's 'abominable mystery.’ The Christian Science Monitor, May 18, 2006 p02. The Jane Goodall Institute Natural History Museum: Ancient Birds Core Case Study Blowing in the Wind: A Story of Connections Wind connects most life on earth. Keeps tropics from being unbearably hot. Prevents rest of world from freezing. Figure 5-1 CLIMATE: A BRIEF INTRODUCTION Weather is a local area’s short-term physical conditions such as temperature and precipitation. Climate is a region’s average weather conditions over a long time. Latitude and elevation help determine climate. Earth’s Current Climate Zones Figure 5-2 Animation: Climate and Ocean Currents Map PLAY ANIMATION Animation: Air Circulation and Climate PLAY ANIMATION Solar Energy and Global Air Circulation: Distributing Heat Global air circulation is affected by the uneven heating of the earth’s surface by solar energy, seasonal changes in temperature and precipitation. Figure 5-3 Spring (sun aims directly at equator) Winter (northern hemisphere 23.5 ° tilts away from sun) Solar radiation Summer (northern hemisphere tilts toward sun) Fall (sun aims directly at equator) Fig. 5-3, p. 102 Video: Seasonal Variation PLAY VIDEO Coriolis Effect Global air circulation is affected by the rotation of the earth on its axis. Figure 5-4 Cold deserts Westerlies Northeast trades Forests Hot deserts Forests Equator Southeast trades Westerlies Hot deserts Forests Cold deserts Fig. 5-4, p. 102 Convection Currents Global air circulation is affected by the properties of air water, and land. Figure 5-5 LOW PRESSURE Cool, dry air HIGH PRESSURE Heat released radiates to space Condensation Falls, is compressed, warms and precipitation Rises, expands, cools Warm, dry air Hot, wet air Flows toward low pressure, picks up moisture and heat HIGH Moist surface warmed PRESSURE by sun LOW PRESSURE Fig. 5-5, p. 103 Convection Cells Heat and moisture are distributed over the earth’s surface by vertical currents, which form six giant convection cells at different latitudes. Figure 5-6 Cell 3 North Cold, dry air falls Moist air rises — rain Polar cap Arctic tundra Evergreen 60°coniferous forest Temperate deciduous forest and grassland 30°Tropical Desert Cell 2 North Cool, dry air falls Cell 1 North deciduous forest 0°Equator Tropical deciduous 30°forest Tropical rain forest Desert Temperate deciduous 60°forest and grassland Cell 1 South Cool, dry air falls Cell 2 South Polar cap Cold, dry air falls Moist air rises, cools, and releases Moisture as rain Moist air rises — rain Cell 3 South Fig. 5-6, p. 103 Animation: Air Circulation PLAY ANIMATION Ocean Currents: Distributing Heat and Nutrients Ocean currents influence climate by distributing heat from place to place and mixing and distributing nutrients. Figure 5-7 (a) Rays of sunlight penetrate the lower atmosphere and warm the earth's surface. (b) The earth's surface absorbs much of the incoming solar radiation and degrades it to longer-wavelength infrared (IR) radiation, which rises into the lower atmosphere. Some of this IR radiation escapes into space as heat, and some is absorbed by molecules of greenhouse gases and emitted as even longer-wavelength IR radiation, which warms the lower atmosphere. (c) As concentrations of greenhouse gases rise, their molecules absorb and emit more infrared radiation, which adds more heat to the lower atmosphere. Fig. 5-7, p. 104 Animation: Greenhouse Effect PLAY ANIMATION Animation: Increasing Greenhouse Gases PLAY ANIMATION Ocean Currents: Distributing Heat and Nutrients Global warming: Considerable scientific evidence and climate models indicate that large inputs of greenhouse gases from anthropogenic activities into the troposphere can enhance the natural greenhouse effect and change the earth’s climate in your lifetime. Video: Global Warming This video clip is available in CNN Today Videos for Environmental Science, 2004, Volume VII. Instructors, contact your local sales representative to order this volume, while supplies last. Animation: El Nino Southern Oscillation PLAY ANIMATION Topography and Local Climate: Land Matters Interactions between land and oceans and disruptions of airflows by mountains and cities affect local climates. Figure 5-8 Prevailing winds pick up moisture from an ocean. On the windward side of a mountain range, air rises, cools, and releases moisture. On the leeward side of the mountain range, air descends, warms, and Releases little moisture. Dry habitats Moist habitats Fig. 5-8, p. 105 Animation: Coastal Breezes PLAY ANIMATION Animation: Upwelling Along Western Coasts PLAY ANIMATION BIOMES: CLIMATE AND LIFE ON LAND Different climates lead to different communities of organisms, especially vegetation. Biomes – large terrestrial regions characterized by similar climate, soil, plants, and animals. Each biome contains many ecosystems whose communities have adapted to differences in climate, soil, and other environmental factors. BIOMES: CLIMATE AND LIFE ON LAND Figure 5-9 Tropic of Cancer Equator High mountains Polar ice Polar grassland (arctic tundra) Temperate grassland Tropical grassland (savanna) Chaparral Coniferous forest Temperate deciduous forest Tropical forest Desert Tropic of Capricorn Fig. 5-9, p. 106 Animation: Biomes Map PLAY ANIMATION BIOMES: CLIMATE AND LIFE ON LAND Biome type is determined by precipitation, temperature and soil type Figure 5-10 Polar Tundra Subpolar Temperate Coniferous forest Desert Deciduous Forest Grassland Chaparral Tropical Desert Rain forest Savanna Tropical seasonal forest Scrubland Fig. 5-10, p. 107 BIOMES: CLIMATE AND LIFE ON LAND Parallel changes occur in vegetation type occur when we travel from the equator to the poles or from lowlands to mountaintops. Figure 5-11 Elevation Mountain ice and snow Tundra (herbs, lichens, mosses) Coniferous Forest Latitude Deciduous Forest Tropical Forest Tropical Forest Deciduous Coniferous Tundra (herbs, Forest Forest lichens, mosses) Polar ice and snow Fig. 5-11, p. 108 DESERT BIOMES Deserts are areas where evaporation exceeds precipitation. Deserts have little precipitation and little vegetation. Found in tropical, temperate and polar regions. Desert plants have adaptations that help them stay cool and get enough water. Video: Desertification This video clip is available in CNN Today Videos for Environmental Science, 2004, Volume VII. Instructors, contact your local sales representative to order this volume, while supplies last. Video: Desertification in China PLAY VIDEO From ABC News, Environmental Science in the Headlines, 2005 DVD. DESERT BIOMES Variations in annual temperature (red) and precipitation (blue) in tropical, temperate and cold deserts. Figure 5-12 Freezing point Month Mean monthly precipitation (mm) Mean monthly temperature (C) Tropical Desert Fig. 5-12a, p. 109 Freezing point Month Mean monthly precipitation (mm) Mean monthly temperature (C) Temperate Desert Fig. 5-12b, p. 109 Freezing point Month Mean monthly precipitation (mm) Mean monthly temperature (°C) Polar Desert Fig. 5-12c, p. 109 DESERT BIOMES The flora and fauna in desert ecosystems adapt to their environment through their behavior and physiology. Figure 5-13 Red-tailed hawk Gambel's Quail Yucca Jack rabbit Agave Collared lizard Prickly pear cactus Roadrunner Darkling Beetle Bacteria Diamondback rattlesnake Producer to primary consumer Fungi Kangaroo rat Primary to secondary consumer Secondary to higher-level consumer All producers and consumers to decomposers Fig. 5-13, p. 110 GRASSLANDS AND CHAPARRAL BIOMES Variations in annual temperature (red) and precipitation (blue). Figure 5-14 Freezing point Month Mean monthly precipitation (mm) Mean monthly temperature (C) Tropical grassland (savanna) Fig. 5-14a, p. 112 Freezing point Month Mean monthly precipitation (mm) Mean monthly temperature (C) Temperate grassland Fig. 5-14b, p. 112 Freezing point Month Mean monthly precipitation (mm) Mean monthly temperature (C) Polar grassland (arctic tundra) Fig. 5-14c, p. 112 Video: Caribou PLAY VIDEO Video: Tundra Flyover PLAY VIDEO GRASSLANDS AND CHAPARRAL BIOMES Grasslands (prairies) occur in areas too moist for desert and too dry for forests. Savannas are tropical grasslands with scattered tree and herds of hoofed animals. Temperate Grasslands The cold winters and hot dry summers have deep and fertile soil that make them ideal for growing crops and grazing cattle. Figure 5-15 Temperate Grasslands Temperate tallgrass prairie ecosystem in North America. Figure 5-16 Golden eagle Pronghorn antelope Grasshopper sparrow Coyote Grasshopper Blue stem grass Prairie dog Bacteria Fungi Prairie Coneflower Producer to primary consumer Primary to secondary consumer Secondary to higher-level consumer All producers and consumers to decomposers Fig. 5-15, p. 113 Animation: Prairie Food Web PLAY ANIMATION Polar Grasslands Polar grasslands are covered with ice and snow except during a brief summer. Figure 5-17 Long-tailed jaeger Grizzly bear Caribou Horned lark Willow ptarmigan Mosquito Snowy owl Arctic fox Dwarf Willow Lemming Mountain Cranberry Moss campion Producer to primary consumer Primary to secondary consumer Secondary to higher-level consumer All producers and consumers to decomposers Fig. 5-17, p. 114 Chaparral Chaparral has a moderate climate but its dense thickets of spiny shrubs are subject to periodic fires. Figure 5-18 FOREST BIOMES Variations in annual temperature (red) and precipitation (blue) in tropical, temperate, and polar forests. Figure 5-19 Freezing point Month Mean monthly precipitation (mm) Mean monthly temperature (C) Tropical rain forest Fig. 5-19a, p. 116 Freezing point Month Mean monthly precipitation (mm) Mean monthly temperature (C) Temperate deciduous forest Fig. 5-19b, p. 116 Freezing point Month Mean monthly precipitation (mm) Mean monthly temperature (C) Polar evergreen coniferous forest (boreal forest, taiga) Fig. 5-19c, p. 116 FOREST BIOMES Forests have enough precipitation to support stands of trees and are found in tropical, temperate, and polar regions. Tropical Rain Forest Tropical rain forests have heavy rainfall and a rich diversity of species. Found near the equator. Have year-round uniformity warm temperatures and high humidity. Figure 5-20 Ocelot Harpy eagle Blue and gold macaw Climbing monstera palm Slaty-tailed trogon Squirrel monkeys Katydid Green tree snake Tree frog Ants Bacteria Bromeliad Fungi Producer to primary consumer Primary to secondary consumer Secondary to higher-level consumer All producers and consumers to decomposers Fig. 5-20, p. 117 Animation: Rainforest Food Web PLAY ANIMATION Tropical Rain Forest Filling such niches enables species to avoid or minimize competition and coexist Figure 5-21 Emergent layer Harpy eagle Toco toucan Canopy Understory Woolly opossum Shrub layer Brazilian tapir Black-crowned antipitta Ground layer Fig. 5-21, p. 118 Temperate Deciduous Forest Most of the trees survive winter by dropping their leaves, which decay and produce a nutrientrich soil. Figure 5-22 Broad-winged hawk Hairy Woodpecker Gray Squirrel White oak White-tailed deer White-footed mouse Metallic wood-boring beetle and Larvae Mountain Winterberry Shagbark hickory Fungi May beetle Long-tailed weasel Bacteria Producer to primary consumer Racer Wood frog Primary to secondary consumer Secondary to higher-level consumer All producers and consumers to decomposers Fig. 5-22, p. 120 Evergreen Coniferous Forests Consist mostly of cone-bearing evergreen trees that keep their needles year-round to help the trees survive long and cold winters. Figure 5-23 Great horned owl Blue jay Marten Balsam fir Moose White Spruce Wolf Bebb willow Pine sawyer beetle and larvae Snowshoe hare Fungi Starflower Bacteria Producer to primary consumer Primary Secondary to to secondary higher-level consumer consumer Bunchberry All producers and consumers to decomposers Fig. 5-23, p. 121 Video: Sequoias PLAY VIDEO Temperate Rain Forests Coastal areas support huge cone-bearing evergreen trees such as redwoods and Douglas fir in a cool moist environment. Figure 5-24 MOUNTAIN BIOMES High-elevation islands of biodiversity Often have snowcovered peaks that reflect solar radiation and gradually release water to lowerelevation streams and ecosystems. Figure 5-25 HUMAN IMPACTS ON TERRESTRIAL BIOMES Human activities have damaged or disturbed more than half of the world’s terrestrial ecosystems. Humans have had a number of specific harmful effects on the world’s deserts, grasslands, forests, and mountains. Natural Capital Degradation Desert Large desert cities Soil destruction by off-road vehicles Soil salinization from irrigation Depletion of groundwater Land disturbance and pollution from mineral extraction Fig. 5-26, p. 123 Natural Capital Degradation Grasslands Conversion to cropland Release of CO2 to atmosphere from grassland burning Overgrazing by livestock Oil production and off-road vehicles in arctic tundra Fig. 5-27, p. 123 Natural Capital Degradation Forests Clearing for agriculture, livestock grazing, timber, and urban development Conversion of diverse forests to tree plantations Damage from off-road vehicles Pollution of forest streams Fig. 5-28, p. 124 Natural Capital Degradation Mountains Agriculture Timber extraction Mineral extraction Hydroelectric dams and reservoirs Increasing tourism Urban air pollution Increased ultraviolet radiation from ozone depletion Soil damage from off-road vehicles Fig. 5-29, p. 124 Video: Eagle Fishing PLAY VIDEO Video: Gopher PLAY VIDEO Video: Grizzly Bears PLAY VIDEO Video: Owl Hunting PLAY VIDEO