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 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