BIOLOGY CONCEPTS & CONNECTIONS Fourth Edition Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Neil A. Campbell Jane B. Reece Lawrence G. Mitchell Martha R. Taylor From PowerPoint ® Lectures for Biology: Concepts & Connections CHAPTER 34 The Biosphere: An Introduction to Earth's Diverse Environments Modules 34.1 – 34.6

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Ecology is the scientific study of the interactions of organisms with their environment The ocean is Earth’s largest and least explored ecosystem Recent explorations of the deep sea have brought previously unknown species to light, such as this “mystery squid” A Mysterious Giant of the Deep

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Deep-sea submersibles like Alvin allow the exploration of the deep sea –It can accommodate a pilot and two other people –It is equipped with instruments to view and sample the ocean at depths of up to 2,500m

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Scientists have found seafloor life whose ultimate energy source is not sunlight, but energy that comes from the interior of the planet –This energy is emitted from hydrothermal vents near the edges of Earth’s crustal plates

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Many animals thrive in the extreme environment around hydrothermal vents –Tube worms were unknown to science until hydrothermal vents were explored –They live on energy extracted from chemicals by bacteria

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Ecologists study environmental interactions at the organism, population, community, and ecosystem levels –These clams that live near an ocean vent constitute a population 34.1 Ecologists study how organisms interact with their environment at several levels Figure 34.1

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Ecosystem interactions involve living (biotic) communities and nonliving (abiotic) components –Abiotic components include energy, nutrients, gases, and water Organisms are affected by their environment –But their presence and activities often change the environment they inhabit

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The global ecosystem is called the biosphere –It is the sum of all the Earth's ecosystems –The biosphere is the most complex level in ecology 34.2 The biosphere is the total of all of Earth's ecosystems THE BIOSPHERE Figure 34.2A

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The biosphere is self-contained –except for energy obtained from the sun and heat lost to space Patchiness characterizes the biosphere –Patchiness occurs in the distribution of deserts, grasslands, forests, and lakes –Each habitat has a unique community of species Figure 34.2B

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Human activities affect all parts of the biosphere –One example is the widespread use of chemicals 34.3 Connection: Environmental problems reveal the limits of the biosphere

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Rachel Carson was one of the first to perceive the global dangers of pesticide abuse Figure 34.3 –Carson documented her concerns in the 1962 book Silent Spring –This book played a key role in the awakening of environmental awareness

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Chemical pesticides are concentrated in food chains by biological magnification Figure 38.3B DDT in water ppm DDT in zooplankton 0.04 ppm DDT in small fish 0.5 ppm DDT in large fish 2 ppm DDT in fish-eating birds 25 ppm DDT concentration: increase of 10 million times

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The most important abiotic factors that determine the biosphere's structure and dynamics include –solar energy –water –temperature 34.4 Physical and chemical factors influence life in the biosphere

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Disturbances such as fires, hurricanes, and volcanic eruptions are also abiotic factors Figure 34.4

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The presence and success of a species in a particular place depends upon its ability to adapt Natural selection adapts organisms to abiotic and biotic factors –Biotic factors include predation and competition 34.5 Organisms are adapted to abiotic and biotic factors by natural selection Figure 34.5

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Climate often determines the distribution of communities Earth's global climate patterns are largely determined by the input of solar energy and the planet's movement in space 34.6 Regional climate influences the distribution of biological communities

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Most climatic variations are due to the uneven heating of Earth's surface –This is a result of the variation in solar radiation at different latitudes Figure 34.6A Low angle of incoming sunlight Sunlight directly overhead Low angle of incoming sunlight Atmosphere North Pole 60º N 30º N Tropic of Cancer 0º (equator) 30º S 60º S South Pole Tropic of Capricorn

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The seasons of the year result from the permanent tilt of the plant on its axis as it orbits the sun Figure 34.6B JUNE SOLSTICE (Northern Hemisphere tilts toward sun) MARCH EQUINOX (equator faces sun directly) DECEMBER SOLSTICE (Northern Hemisphere tilts away from sun) SEPTEMBER EQUINOX

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The tropics experience the greatest annual input and least seasonal variation in solar radiation The direct intense solar radiation near the equator has an impact on the global patterns of rainfall and winds

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Figure 34.6C Ascending moist air releases moisture Doldrums TROPICS 30º 23.5º 0º 23.5º 30º Descending dry air absorbs moisture TEMPERATE ZONE Descending dry air absorbs moisture TEMPERATE ZONE Trade winds

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Warm, moist air at the equator rises As the air rises, it cools and releases much of its water content –This results in the abundant precipitation typical of most tropical regions After losing their moisture over equatorial zones, high altitude air masses spread away from the equator

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings They cool and descend again at latitudes of about 30° north and south –This explains the locations of the world's great deserts As the dry air descends, some of it spreads back toward the equator –This creates the cooling trade winds that dominate the tropics

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Temperate zones are located between the tropics and the Arctic Circle in the north and the Antarctic Circle in the south –They have seasonal variations in climate –The temperatures are more moderate than in the tropic or polar regions

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Prevailing winds result from the combined effects of the rising and falling of air masses and Earth's rotation –In the tropics, Earth's rapidly moving surface deflects vertically circulating air, making the winds blow from east to west –In temperate zones, the slower-moving surface produces the westerlies, winds that blow from west to east Figure 34.6D

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Ocean currents have a profound effect on regional climates by warming or cooling coastal areas –They are created by winds, planet rotation, unequal heating of surface waters, and the locations and shapes of continents

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Local high temperatures for August 6, 2000, in Southern California Figure 34.6E Fresno 100º Pacific Ocean Santa Barbara 73º Los Angeles (Airport) 75º Burbank 90º Bakersfield 100º Santa Ana 84º Riverside 96º San Bernardino 100º Palm Springs 106º Death Valley 119º 40 miles San Diego 72º Key 70s (ºF) 80s 90s 100s 110s

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Landforms, such as mountains, can affect local climate Figure 34.6F Pacific Ocean Coast Range Wind direction Cascade Range East

BIOLOGY CONCEPTS & CONNECTIONS Fourth Edition Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Neil A. Campbell Jane B. Reece Lawrence G. Mitchell Martha R. Taylor From PowerPoint ® Lectures for Biology: Concepts & Connections CHAPTER 34 The Biosphere: An Introduction to Earth's Diverse Environments Modules 34.7 – 34.11

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Oceans cover about 75% of the Earth's surface Light and the availability of nutrients are the major factors that shape aquatic communities 34.7 Oceans occupy most of Earth's surface AQUATIC BIOMES

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Estuaries are productive areas where rivers meet the ocean –The saltiness of estuaries ranges from less than 1% to 3% –They provide nursery areas for oysters, crabs, and many fishes –They are often bordered by extensive coastal wetlands Figure 34.7A

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The intertidal zone is the wetland at the edge of an estuary or ocean, where water meets land –Salt marshes, sand and rocky beaches, and tide pools are part of the intertidal zone –It is often flooded by high tides and then left dry during low tides Figure 34.7B

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Abiotic conditions dictate the kinds of communities that ocean zones can support Figure 34.7C Intertidal zone Continental zone Benthic zone (seafloor) Photic zone Aphotic zone Pelagic zone

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The pelagic zone is the open ocean –It supports highly motile animals such as fishes, squids, and marine mammals –Phytoplankton and zooplankton drift in the pelagic zone The benthic zone is the ocean bottom –It supports a variety of organisms based upon water depth and light penetration

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The photic zone is the portion of the ocean into which light penetrates –Photosynthesis occurs here The aphotic zone is a vast, dark region of the ocean –It is the most extensive part of the biosphere –Although there is no light, a diverse and dense population inhabits this zone

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Coral reefs are found in warm tropical waters above the continental shelf –They support a huge diversity of invertebrates and fishes Coral reefs are easily degraded by –pollution –native and introduced predators –human souvenir hunters Figure 34.7D

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Lake and pond communities are shaped by –light –temperature –the availability of nutrients and dissolved oxygen 34.8 Freshwater biomes include lakes, ponds, rivers, streams, and wetlands

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings A river environment changes greatly between its source and its mouth –Temperature, nutrients, currents, and water clarity vary at different points Figure 34.8A

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Wetlands are among the richest biomes in terms of species diversity Figure 34.8B

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Climatic differences, mainly temperature and rainfall, shape the major biomes that cover Earth's land surface Biomes tend to grade into each other Within each biome there is local variation –This gives vegetation a patchy, rather than uniform, appearance 34.9 Terrestrial biomes reflect regional variations in climate TERRESTRIAL BIOMES

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Major terrestrial biomes Figure º N Equator 30º S Tropical forest Savanna Desert Polar and high-mountain ice Chaparral Temperate grassland Temperate deciduous forest Coniferous forest Tundra (arctic and alpine)

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Several types of tropical forests occur in the warm, moist belt along the equator Tropical forests cluster near the equator Figure 34.10

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The tropical rain forest is the most diverse ecosystem on Earth Large-scale human destruction of tropical rain forests continues to endanger many species –It may also alter world climate

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The Luquillo Experimental Forest in Puerto Rico allows ecologists to study the effects of disruption on tropical forests –It contains deforested as well as still-forested areas Talking About Science: Ecologist Arial Lugo studies tropical forests in Puerto Rico Figure 34.11B

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The forest ecologist Dr. Ariel Lugo has been one of the key scientists at the Luquillo Experimental Forest –He and other scientists have offered valuable insight into the peril these forests face as well as the promise they hold Studies indicate that tropical forests recover from natural disasters much more readily than they do from human destruction Figure 34.11A

BIOLOGY CONCEPTS & CONNECTIONS Fourth Edition Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Neil A. Campbell Jane B. Reece Lawrence G. Mitchell Martha R. Taylor From PowerPoint ® Lectures for Biology: Concepts & Connections CHAPTER 34 The Biosphere: An Introduction to Earth's Diverse Environments Modules – 34.18

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Drier, tropical areas and some nontropical areas are characterized by the savanna Savannas are grasslands with scattered trees Figure 34.12

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Deserts are the driest of all terrestrial biomes –They are characterized by low and unpredictable rainfall Deserts are defined by their dryness Figure –Desertification is a significant environmental problem

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The chaparral biome is a shrubland with cool, rainy winters and dry, hot summers Chaparral vegetation is adapted to periodic fires Spiny shrubs dominate the chaparral Figure 34.14

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Temperate grasslands are found in the interiors of the continents, where winters are cold –Drought, fires, and grazing animals prevent trees from growing –Farms have replaced most of North America's temperate grasslands Temperate grasslands include the North American prairie Figure 34.15

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Temperate deciduous forests grow where there is sufficient moisture to support the growth of large trees –Nearly all of the original deciduous forests in North America have been drastically altered by agriculture and urban development Deciduous trees dominate temperate forests Figure 34.16

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The northern coniferous forest, or taiga, is the largest terrestrial biome on Earth Coniferous forests are often dominated by a few species of trees Figure 34.17

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The taiga is characterized by long, cold winters and short, wet summers Coastal coniferous forests of the Pacific Northwest are actually temperate rain forests

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings The arctic tundra lies between the taiga and the permanently frozen polar regions –It is a treeless biome characterized by extreme cold, wind, and permafrost –Permafrost is continuously frozen subsoil Long, bitter-cold winters characterize the tundra Figure 34.18