Chapter 6Chapter 6

Climate and Terrestrial Climate and Terrestrial BiodiversityBiodiversity

Section 6-2Section 6-2

INTRO TOINTRO TO

CLIMATE CLIMATE

Blowing in the Wind: Blowing in the Wind: A Story of ConnectionsA Story of Connections

Wind connects Wind connects most life on earth.most life on earth. Keeps tropics from Keeps tropics from

being unbearably being unbearably hot.hot.

Prevents rest of Prevents rest of world from world from freezing.freezing.

Figure 5-1Figure 5-1

CLIMATE: A BRIEF INTRODUCTIONCLIMATE: 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 ZonesEarth’s Current Climate Zones

Figure 5-2Figure 5-2

Solar Energy and Global Air Solar Energy and Global Air Circulation: Distributing HeatCirculation: Distributing Heat

Global air circulation Global air circulation is affected by is affected by

• the uneven heating the uneven heating of the earth’s of the earth’s surface by solar surface by solar energyenergy

• seasonal changes in seasonal changes in temperature and temperature and precipitation.precipitation.

Figure 5-3Figure 5-3

Coriolis EffectCoriolis Effect

Global air Global air circulation is circulation is affected by the affected by the rotation of the rotation of the earth on its axis.earth on its axis.

Figure 5-4Figure 5-4

Convection CurrentsConvection Currents

Global air Global air circulation is circulation is affected by the affected by the properties of air properties of air water, and land.water, and land.

Figure 5-5Figure 5-5

Convection CellsConvection Cells

Heat and moisture Heat and moisture are distributed over are distributed over the earth’s surface by the earth’s surface by vertical currents, vertical currents, which form six giant which form six giant convection cells at convection cells at different latitudes.different latitudes.

Figure 5-6Figure 5-6

Ocean Currents: Ocean Currents: Distributing Heat and NutrientsDistributing Heat and Nutrients

Ocean currents influence climate by Ocean currents influence climate by distributing heat from place to place and distributing heat from place to place and mixing and distributing nutrients.mixing and distributing nutrients.

Figure 5-7Figure 5-7

Topography and Local Climate:Topography and Local Climate:Land MattersLand Matters

Interactions between land and oceans and Interactions between land and oceans and disruptions of airflows by mountains and disruptions of airflows by mountains and cities affect local climates.cities affect local climates.

Figure 5-8Figure 5-8

Section 6-3Section 6-3

INTRO TOINTRO TO

BIOMES BIOMES

Biomes Animation

BIOMES: BIOMES: CLIMATE AND LIFE ON LANDCLIMATE AND LIFE ON LAND

Different climates lead to different Different climates lead to different communities of organisms, especially communities of organisms, especially vegetation.vegetation.

Biomes – large terrestrial regions characterized Biomes – large terrestrial regions characterized by similar climate, soil, plants, and animals.by similar climate, soil, plants, and animals.

Each biome contains many ecosystems whose Each biome contains many ecosystems whose communities have adapted to differences in communities have adapted to differences in climate, soil, and other environmental factors.climate, soil, and other environmental factors.

BIOMES: BIOMES: CLIMATE AND LIFE ON LANDCLIMATE AND LIFE ON LAND

Figure 5-9Figure 5-9

BIOMES: BIOMES: CLIMATE AND LIFE ON LANDCLIMATE AND LIFE ON LAND

Biome type is determined by precipitation, Biome type is determined by precipitation, temperature and soil typetemperature and soil type

Figure 5-10Figure 5-10

BIOMES: BIOMES: CLIMATE AND LIFE ON LANDCLIMATE AND LIFE ON LAND

Parallel changes occur in vegetation type Parallel changes occur in vegetation type occur when we travel from the equator to the occur when we travel from the equator to the poles or from lowlands to mountaintops.poles or from lowlands to mountaintops.

Figure 5-11Figure 5-11

Summary of BiomesSummary of Biomes

Biomes – large terrestrial regions characterized by similar Biomes – large terrestrial regions characterized by similar climate, soil, plants, and animals.climate, soil, plants, and animals.

Determined by climate (average Temperature & Determined by climate (average Temperature & Precipitation, Soil) Precipitation, Soil)

Parallel trends as you move from the equator to the poles Parallel trends as you move from the equator to the poles and as you move from lower to higher elevation.and as you move from lower to higher elevation.

Tropical (near equator) -> Temperate -> Cold Tropical (near equator) -> Temperate -> Cold

Major Categories of BiomesMajor Categories of Biomes1. Deserts: Low Rainfall (evaporation exceeds precipitation) 1. Deserts: Low Rainfall (evaporation exceeds precipitation)

a. Tropical: Parts of middle east & Africa)a. Tropical: Parts of middle east & Africa)

b. Temperate (U.S. ex. Sonoran)b. Temperate (U.S. ex. Sonoran)

c. Cold: Gobi (Mongolia)c. Cold: Gobi (Mongolia)

2. Forests (large trees dominate) 2. Forests (large trees dominate)

a. Tropical: Lots of rainfall (parts of S. America, Africa, Asia)a. Tropical: Lots of rainfall (parts of S. America, Africa, Asia)

b. Temperate: 4 seasons b. Temperate: 4 seasons

Deciduous (Eastern U.S.)Deciduous (Eastern U.S.)

Rainforest (Parts of Washington State, etc.)Rainforest (Parts of Washington State, etc.)

c. Cold: Taiga (Coniferous or Boreal Forest), Canada, parts c. Cold: Taiga (Coniferous or Boreal Forest), Canada, parts of U.S. of U.S.

Major Categories of Biomes (Continued)Major Categories of Biomes (Continued)

3. Grasslands (medium rainfall, dominated by 3. Grasslands (medium rainfall, dominated by grasses)grasses)

a. Tropical: Savannaa. Tropical: Savanna

b. Temperate: Prairie lands in U.S. b. Temperate: Prairie lands in U.S.

c. Cold: Tundra (Alaska, parts of Canada, poles)c. Cold: Tundra (Alaska, parts of Canada, poles)

Section 6-4Section 6-4

DESERTS DESERTS

DESERT BIOMESDESERT BIOMES Deserts are areas where evaporation Deserts are areas where evaporation

exceeds precipitation.exceeds precipitation.

Deserts have little precipitation and little Deserts have little precipitation and little vegetation.vegetation. Found in tropical, temperate and polar regions.Found in tropical, temperate and polar regions.

Desert plants have adaptations that help Desert plants have adaptations that help them stay cool and get enough water.them stay cool and get enough water.

DESERT BIOMESDESERT BIOMES

Variations in Variations in annual annual temperature (red) temperature (red) and precipitation and precipitation (blue) in tropical, (blue) in tropical, temperate and temperate and cold deserts.cold deserts.

Figure 5-12Figure 5-12

Fig. 5-12a, p. 109

Tropical Desert

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Temperate Desert

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Fig. 5-12c, p. 109

Polar Desert

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DESERT BIOMESDESERT BIOMES

The flora and The flora and fauna in desert fauna in desert ecosystems ecosystems adapt to their adapt to their environment environment through their through their behavior and behavior and physiology.physiology.

Figure 5-13Figure 5-13

Section 6-5Section 6-5

GRASSSLANDS &GRASSSLANDS &

CHAPARRALSCHAPARRALS

GRASSLANDS AND CHAPARRAL GRASSLANDS AND CHAPARRAL BIOMESBIOMES

Variations in Variations in annual annual temperature temperature (red) and (red) and precipitation precipitation (blue).(blue).

Figure 5-14Figure 5-14

GRASSLANDS AND CHAPARRAL GRASSLANDS AND CHAPARRAL BIOMESBIOMES

Grasslands (prairies) occur in areas too moist Grasslands (prairies) occur in areas too moist for desert and too dry for forests.for desert and too dry for forests.

Savannas are tropical grasslands with Savannas are tropical grasslands with scattered tree and herds of hoofed animals.scattered tree and herds of hoofed animals.

Fig. 5-14a, p. 112

Tropical grassland (savanna)

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Fig. 5-14b, p. 112

Temperate grassland

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Temperate GrasslandsTemperate Grasslands

The cold winters and The cold winters and hot dry summers have hot dry summers have deep and fertile soil deep and fertile soil that make them ideal that make them ideal for growing crops and for growing crops and grazing cattle.grazing cattle.

Temperate tall-grass Temperate tall-grass prairie ecosystem in prairie ecosystem in North America.North America.

Figure 5-15Figure 5-15

Fig. 5-14c, p. 112

Polar grassland (arctic tundra)

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Polar GrasslandsPolar Grasslands

Polar grasslands Polar grasslands are covered with ice are covered with ice and snow except and snow except during a brief during a brief summer.summer.

Figure 5-17Figure 5-17

ChaparralChaparral

Chaparral has a Chaparral has a moderate moderate climate but its climate but its dense thickets of dense thickets of spiny shrubs are spiny shrubs are subject to subject to periodic fires.periodic fires.

Figure 5-18Figure 5-18

Section 6-6Section 6-6

FORESTSFORESTS

FOREST BIOMESFOREST BIOMES Variations in annual Variations in annual

temperature (red) and temperature (red) and precipitation (blue) in precipitation (blue) in tropical, temperate, and tropical, temperate, and polar forests.polar forests.

Forests have enough Forests have enough precipitation to support precipitation to support stands of trees and are stands of trees and are found in tropical, found in tropical, temperate, and polar temperate, and polar regions.regions.

Figure 5-19Figure 5-19

Fig. 5-19a, p. 116

Tropical rain forest

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• 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.

Tropical Rain ForestTropical Rain Forest

Filling such niches enables species to avoid Filling such niches enables species to avoid or minimize competition and coexistor minimize competition and coexist

Figure 5-21Figure 5-21

Fig. 5-19b, p. 116

Temperate deciduous forest

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Temperate Deciduous ForestTemperate Deciduous Forest

Most of the trees Most of the trees survive winter by survive winter by dropping their dropping their leaves, which leaves, which decay and decay and produce a nutrient-produce a nutrient-rich soil.rich soil.

Figure 5-22Figure 5-22

Temperate Rain ForestsTemperate Rain Forests

Coastal areas support huge cone-bearing Coastal areas support huge cone-bearing evergreen trees such as redwoods and evergreen trees such as redwoods and Douglas fir in a cool moist environment.Douglas fir in a cool moist environment.

Figure 5-24Figure 5-24

Fig. 5-19c, p. 116

Polar evergreen coniferous forest(boreal forest, taiga)

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Evergreen Coniferous ForestsEvergreen Coniferous Forests

Consist mostly of Consist mostly of cone-bearing cone-bearing evergreen trees that evergreen trees that keep their needles keep their needles year-round to help year-round to help the trees survive the trees survive long and cold long and cold winters.winters.

Figure 5-23Figure 5-23

Section 6-7Section 6-7

MOUNTAIN BIOMESMOUNTAIN BIOMES

MOUNTAIN BIOMESMOUNTAIN BIOMES High-elevation islands High-elevation islands

of biodiversity of biodiversity

Often have snow-Often have snow-covered peaks that covered peaks that reflect solar radiation reflect solar radiation and gradually release and gradually release water to lower-water to lower-elevation streams and elevation streams and ecosystems.ecosystems.

Figure 5-25Figure 5-25

HUMAN IMPACTS ON HUMAN IMPACTS ON TERRESTRIAL BIOMESTERRESTRIAL BIOMES

Human activities have damaged or disturbed Human activities have damaged or disturbed more than half of the world’s terrestrial more than half of the world’s terrestrial ecosystems.ecosystems.

Humans have had a number of specific Humans have had a number of specific harmful effects on the world’s deserts, harmful effects on the world’s deserts, grasslands, forests, and mountains.grasslands, forests, and mountains.

Fig. 5-26, p. 123

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. 5-27, p. 123

Oil production and off-road vehicles in arctic tundra

Overgrazing by livestock

Release of CO2 to atmosphere from grassland burning

Conversion to cropland

Grasslands

Natural Capital Degradation

Fig. 5-28, p. 124

Clearing for agriculture, livestock grazing, timber, and urban development

Conversion of diverse forests to tree plantations

Damage from off-road vehicles

Natural Capital Degradation

Forests

Pollution of forest streams

Fig. 5-29, p. 124

Natural Capital Degradation

Mountains

Agriculture

Timber extraction

Mineral extraction

Hydroelectric dams and reservoirs

Increasing tourism

Urban air pollution

Increased ultraviolet radiationfrom ozone depletion

Soil damage from off-roadvehicles

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?

Chapter Overview Questions (cont’d)

• What are the major types of grassland biomes?

• What are the major types of forest and mountain biomes?

• How have human activities affected the world’s desert, grassland, forest, and mountain biomes?