Climate and Terrestrial Biodiversity Chapter 7

Core Case Study: Connections between Wind, Climate, and Biomes Indirect form of solar energy Circulates Heat Moisture Plant nutrients Soil particles Long-lived air pollutants

Dust Blown from West Africa to the Amazonian Rain Forests

7-1 What Factors Influence Climate? Concept 7-1 An area's climate is determined mostly by solar radiation, the earth’s rotation, global patterns of air and water movement, gases in the atmosphere, and the earth’s surface features.

The Earth Has Many Different Climates (1) Weather Climate Air circulation in lower atmosphere due to Uneven heating of the earth’s surface by the sun Rotation of the earth on its axis Properties of air, water, and land

The Earth Has Many Different Climates (2) Currents Prevailing winds Earth’s rotation Redistribution of heat from the sun Link between air circulation, ocean currents, and biomes

Natural Capital: Generalized Map of the Earth’s Current Climate Zones

Global Air Circulation

Solar energy Air cools and descends at lower latitudes. Cold deserts Air cools and descends at lower latitudes. Westerlies Forests 30°N Northeast trades Hot deserts Warm air rises and moves toward the poles. Forests 0° Solar energy Equator Air cools and descends at lower latitudes. Southeast trades Hot deserts 30°S The highest solar energy input is at the equator. Figure 7.3 Global air circulation. The largest input of solar energy occurs at the equator. As this air is heated it rises and moves toward the poles. However, the earth’s rotation deflects the movement of the air over different parts of the earth. This creates global patterns of prevailing winds that help distribute heat and moisture in the atmosphere. Westerlies Forests Cold deserts 60°S Fig. 7-3, p. 142

Energy Transfer by Convection in the Atmosphere

Heat released radiates to space Condensation and precipitation LOW PRESSURE HIGH PRESSURE Heat released radiates to space Condensation and precipitation Cool, dry air Falls, is compressed, warms Rises, expands, cools Warm, dry air Hot, wet air Figure 7.4 Energy transfer by convection in the atmosphere. Convection occurs when hot and wet warm air rises, cools, and releases heat and moisture as precipitation (right side). Then the denser cool, dry air sinks, gets warmer, and picks up moisture as it flows across the earth’s surface to begin the cycle again. Flows toward low pressure, picks up moisture and heat HIGH PRESSURE LOW PRESSURE Moist surface warmed by sun Fig. 7-4, p. 143

Connected Deep and Shallow Ocean Currents

Warm, less salty, shallow current Figure 7.5 Connected deep and shallow ocean currents. A connected loop of shallow and deep ocean currents transports warm and cool water to various parts of the earth. This loop, which rises in some areas and falls in others, results when ocean water in the North Atlantic near Iceland is dense enough (because of its salt content and cold temperature) to sink to the ocean bottom, flow southward, and then move eastward to well up in the warmer Pacific. A shallower return current aided by winds then brings warmer, less salty—and thus less dense—water to the Atlantic. This water can cool and sink to begin this extremely slow cycle again. Question: How do you think this loop affects the climates of the coastal areas around it? Cold, salty, deep current Fig. 7-5, p. 143

Global Air Circulation, Ocean Currents, and Biomes

Moist air rises, cools, and releases moisture as rain Polar cap Arctic tundra Evergreen coniferous forest 60° Temperate deciduous forest and grassland Desert 30° Tropical deciduous forest Equator 0° Tropical rain forest Tropical deciduous forest 30° Desert Figure 7.6 Global air circulation, ocean currents, and biomes. Heat and moisture are distributed over the earth’s surface via six giant convection cells (like the one in Figure 7-4) at different latitudes. The resulting uneven distribution of heat and moisture over the planet’s surface leads to the forests, grasslands, and deserts that make up the earth’s terrestrial biomes. Temperate deciduous forest and grassland 60° Polar cap Fig. 7-6, p. 144

Greenhouse Gases Warm the Lower Atmosphere CO2 CH4 N2O Greenhouse effect Human-enhanced global warming

Flow of Energy to and from the Earth

The Earth’s Surface Features Affect Local Climates Heat absorption by land and water Effect of Mountains Rain shadow effect Cities Microclimates

Rain Shadow Effect

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. Figure 7.7 The rain shadow effect is a reduction of rainfall and loss of moisture from the landscape on the side of a mountain facing away from prevailing surface winds. Warm, moist air in onshore winds loses most of its moisture as rain and snow on the windward slopes of a mountain range. This leads to semiarid and arid conditions on the leeward side of the mountain range and the land beyond. The Mojave Desert in the U.S. state of California and Asia’s Gobi Desert are both produced by this effect. Fig. 7-7, p. 145

7-2 How Does Climate Affect the Nature and Locations of Biomes? Concept 7-2 Differences in average annual precipitation and temperature lead to the formation of tropical, temperate, and cold deserts, grasslands, and forests, and largely determine their locations.

Climate Affects Where Organisms Can Live Major biomes Latitude and elevation Annual precipitation Temperature

The Earth’s Major Biomes

Generalized Effects of Elevation and Latitude on Climate and Biomes

Tundra (herbs, lichens, mosses) Elevation Mountain ice and snow Tundra (herbs, lichens, mosses) Coniferous Forest Deciduous Forest Latitude Tropical Forest Figure 7.9 Generalized effects of elevation (left) and latitude (right) on climate and biomes. Parallel changes in vegetation type occur when we travel from the equator to the poles or from lowlands to mountaintops. Question: How might the components of the left diagram change as the earth warms during this century? Explain. Tropical Forest Deciduous Forest Coniferous Forest Tundra (herbs, lichens, mosses) Polar ice and snow Fig. 7-9, p. 147

Tundra (herbs, lichens, mosses) Elevation Mountain ice and snow Tundra (herbs, lichens, mosses) Coniferous Forest Deciduous Forest Tropical Forest Latitude Tropical Forest Deciduous Forest Coniferous Forest Tundra (herbs, lichens, mosses) Polar ice and snow Figure 7.9 Generalized effects of elevation (left) and latitude (right) on climate and biomes. Parallel changes in vegetation type occur when we travel from the equator to the poles or from lowlands to mountaintops. Question: How might the components of the left diagram change as the earth warms during this century? Explain. Stepped Art Fig. 7-9, p. 147

Natural Capital: Average Precipitation and Average Temperature as Limiting Factors

Decreasing temperature Decreasing precipitation Cold Polar Tundra Subpolar Temperate Coniferous forest Decreasing temperature Desert Deciduous forest Grassland Tropical Chaparral Hot Figure 7.10 Natural capital: average precipitation and average temperature, acting together as limiting factors over a long time, help to determine the type of desert, grassland, or forest biome in a particular area. Although each actual situation is much more complex, this simplified diagram explains how climate helps to determine the types and amounts of natural vegetation found in an area left undisturbed by human activities. (Used by permission of Macmillan Publishing Company, from Derek Elsom, The Earth, New York: Macmillan, 1992. Copyright © 1992 by Marshall Editions Developments Limited). Desert Wet Rain forest Savanna Dry Tropical seasonal forest Scrubland Decreasing precipitation Fig. 7-10, p. 147

Science Focus: Staying Alive in the Desert Plant adaptations Animal strategies and adaptations

There Are Three Major Types of Deserts Tropical deserts Temperate deserts Cold deserts Fragile ecosystem Slow plant growth Low species diversity Slow nutrient recycling Lack of water

Climate Graphs of Three Types of Deserts

Figure 7.11 Climate graphs showing typical variations in annual temperature (red) and precipitation (blue) in tropical, temperate, and cold deserts. Top photo: a popular (but destructive) SUV rodeo in United Arab Emirates (tropical desert). Center photo: saguaro cactus in the U.S. state of Arizona (temperate desert). Bottom photo: a Bactrian camel in Mongolia’s Gobi Desert (cold desert). Question: What month of the year has the highest temperature and the lowest rainfall for each of the three types of deserts? Stepped Art Fig. 7-11, p. 149

There Are Three Major Types of Grasslands (1) Tropical Temperate Cold (arctic tundra)

There Are Three Major Types of Grasslands (2) Tropical Savanna Grazing animals Browsing animals Temperate Tall-grass prairies Short-grass prairies

There Are Three Major Types of Grasslands (3) Arctic tundra: fragile biome Adaptations of plants and animals Permafrost Alpine tundra

Climate Graphs of Tropical, Temperate, and Cold Grasslands

Figure 7.12 Climate graphs showing typical variations in annual temperature (red) and precipitation (blue) in tropical, temperate, and cold (arctic tundra) grassland. Top photo: wildebeests grazing on a savanna in Maasai Mara National Park in Kenya, Africa (tropical grassland). Center photo: wildflowers in bloom on a prairie near East Glacier Park in the U.S. state of Montana (temperate grassland). Bottom photo: arctic tundra (cold grassland) in autumn in front of the Alaska Range, Alaska (USA). Question: What month of the year has the highest temperature and the lowest rainfall for each of the three types of grassland? Stepped Art Fig. 7-12, p. 151

Monoculture Crop Replacing Biologically Diverse Temperate Grassland

Temperate Shrubland: Nice Climate, Risky Place to Live Chaparral Near the sea: nice climate Prone to fires in the dry season

Chaparral Vegetation in Utah, U.S.

Figure 7.14 Chaparral vegetation in the U.S. state of Utah and a typical climate graph. Stepped Art Fig. 7-14, p. 152

There Are Three Major Types of Forests (1) Tropical Temperate Cold Northern coniferous and boreal

There Are Three Major Types of Forests (2) Tropical rain forests Temperature and moisture Stratification of specialized plant and animal niches Little wind: significance Rapid recycling of scarce soil nutrients Impact of human activities

There Are Three Major Types of Forests (3) Temperate deciduous forests Temperature and moisture Broad-leaf trees Slow rate of decomposition: significance Impact of human activities

There Are Three Major Types of Forests (4) Evergreen coniferous forests: boreal and taigas Temperature and moisture Few species of cone: bearing trees Slow decomposition: significance Coastal coniferous forest Temperate rain forests

Climate Graphs of Tropical, Temperate, and Cold Forests

Figure 7.15 Climate graphs showing typical variations in annual temperature (red) and precipitation (blue) in tropical, temperate, and cold (northern coniferous and boreal) forests. Top photo: the closed canopy of a tropical rain forest in the western Congo Basin of Gabon, Africa. Middle photo: a temperate deciduous forest in the U.S. state of Rhode Island during the fall. (Photo 4 in the Detailed Contents shows this same area of forest during winter.) Bottom photo: a northern coniferous forest in the Malheur National Forest and Strawberry Mountain Wilderness in the U.S. state of Oregon. Question: What month of the year has the highest temperature and the lowest rainfall for each of the three types of forest? Stepped Art Fig. 7-15, p. 154

Some Components and Interactions in a Tropical Rain Forest Ecosystem

Climbing monstera palm Ocelot Blue and gold macaw Harpy eagle Squirrel monkeys Climbing monstera palm Katydid Green tree snake Slaty-tailed trogon Tree frog Figure 7.16 Some components and interactions in a tropical rain forest ecosystem. When these organisms die, decomposers break down their organic matter into minerals that plants use. Colored arrows indicate transfers of matter and energy between producers; primary consumers (herbivores); secondary, or higher-level, consumers (carnivores); and decomposers. Organisms are not drawn to scale. See an animation based on this figure at CengageNOW. Ants Bacteria Bromeliad Fungi Producer to primary consumer Primary to secondary consumer Secondary to higher-level consumer All producers and consumers to decomposers Fig. 7-16, p. 155

Stratification of Specialized Plant and Animal Niches in a Tropical Rain Forest

Black-crowned antpitta 45 Harpy eagle Emergent layer 40 35 Toco toucan Canopy 30 25 Height (meters) 20 Under story Wooly opossum 15 Figure 7.17 Stratification of specialized plant and animal niches in a tropical rain forest. Filling such specialized niches enables species to avoid or minimize competition for resources and results in the coexistence of a great variety of species. 10 Brazilian tapir Shrub layer 5 Black-crowned antpitta Ground layer Fig. 7-17, p. 156

Temperate Rain Forest in Washington State, U.S.

Mountains Play Important Ecological Roles Majority of the world’s forests Habitats for endemic species Help regulate the earth’s climate Can affect sea levels Major storehouses of water Role in hydrologic cycle

Mount Rainier National Park in Washington State, U.S.

7-3 How Have We Affected the Word’s Terrestrial Ecosystems? Concept 7-3 In many areas, human activities are impairing ecological and economic services provided by the earth’s deserts, grasslands, forests, and mountains.

Humans Have Disturbed Most of the Earth’s Lands Deserts Grasslands Forests Mountains

What are the Major Human Impacts on Terrestrial Ecosystems?

NATURAL CAPITAL DEGRADATION Major Human Impacts on Terrestrial Ecosystems Deserts Grasslands Forests Mountains Large desert cities Conversion to cropland Clearing for agriculture, livestock grazing, timber, and urban development Agriculture Figure 7.20 Major human impacts on the world’s deserts, grasslands, forests, and mountains. Question: Which two of the impacts on each of these biomes do you think are the most harmful? Timber extraction Soil destruction by off-road vehicles Release of CO2 to atmosphere from burning grassland Mineral extraction Hydroelectric dams and reservoirs Soil salinization from irrigation Conversion of diverse forests to tree plantations Increasing tourism Overgrazing by livestock Urban air pollution Depletion of groundwater Increased ultraviolet radiation from ozone depletion Damage from off-road vehicles Oil production and off-road vehicles in arctic tundra Land disturbance and pollution from mineral extraction Pollution of forest streams Soil damage from off-road vehicles Fig. 7-20, p. 158

NATURAL CAPITAL DEGRADATION Major Human Impacts on Terrestrial Ecosystems Deserts Soil salinization from irrigation Depletion of groundwater Land disturbance and pollution from mineral extraction Grasslands Conversion to cropland Release of CO2 to atmosphere from burning grassland Overgrazing by livestock Oil production and off-road vehicles in arctic tundra 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 Mountains Agriculture Timber extraction Hydroelectric dams and reservoirs Mineral extraction Increasing tourism Urban air pollution Increased ultraviolet radiation from ozone depletion Soil damage from off-road vehicles Large desert cities Figure 7.20 Major human impacts on the world’s deserts, grasslands, forests, and mountains. Question: Which two of the impacts on each of these biomes do you think are the most harmful? Soil destruction by off-road vehicles Stepped Art Fig. 7-20, p. 158