Climate and Terrestrial Biodiversity

1
Chapter 5

• Climate and Terrestrial Biodiversity

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Core Case StudyBlowing 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
3
CLIMATE A BRIEF INTRODUCTION

• Weather is a local areas short-term physical
  conditions such as temperature and precipitation.
• Climate is a regions average weather conditions
  over a long time.
• Latitude and elevation help determine climate.

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Earths Current Climate Zones
Figure 5-2
5
Solar Energy and Global Air Circulation
Distributing Heat

• Global air circulation is affected by the uneven
  heating of the earths surface by solar energy,
  seasonal changes in temperature and precipitation.

Figure 5-3
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Coriolis Effect

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

Figure 5-4
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Convection Currents

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

Figure 5-5
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Convection Cells

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

Figure 5-6
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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
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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 earths climate in your
  lifetime.

11
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.

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Topography and Local ClimateLand Matters

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

Figure 5-8
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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.

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BIOMES CLIMATE AND LIFE ON LAND
Figure 5-9
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BIOMES CLIMATE AND LIFE ON LAND

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

Figure 5-10
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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
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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.

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DESERT BIOMES

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

Figure 5-12
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DESERT BIOMES

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

Figure 5-13
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GRASSLANDS AND CHAPARRAL BIOMES

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

Figure 5-14
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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.

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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
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Temperate Grasslands

• Temperate tall-grass prairie ecosystem in North
  America.

Figure 5-16
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Polar Grasslands

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

Figure 5-17
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Chaparral

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

Figure 5-18
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FOREST BIOMES

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

Figure 5-19
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FOREST BIOMES

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

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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
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Tropical Rain Forest

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

Figure 5-21
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Temperate Deciduous Forest

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

Figure 5-22
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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
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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
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MOUNTAIN BIOMES

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

Figure 5-25
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HUMAN IMPACTS ON TERRESTRIAL BIOMES

• Human activities have damaged or disturbed more
  than half of the worlds terrestrial ecosystems.
• Humans have had a number of specific harmful
  effects on the worlds deserts, grasslands,
  forests, and mountains.

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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
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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
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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
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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