Exploring the Mysterious Giant of the Deep

1. Chapter 34 0 The Biosphere: An Introduction to Earth’s Diverse Environments

2. A Mysterious Giant of the Deep • There are about 1,000 known species of squid • But until recently, no one had reported on this “mystery squid”

3. Deep-sea submersibles • Are allowing scientists to study uncharted depths of the ocean Figure A

4. At depths of up to 2,500 meters • Scientists are observing new environments and a great variety of organisms Figure B Figure C

5. Ecology • Is the scientific study of the interactions of organisms with their environments

6. Figure 34.1 • 34.1 Ecologists study how organisms interact with their environment at several levels • At the organismal level • Ecologists may examine how one kind of organism meets the challenges of its environment

7. At the population level • Ecologists might study factors that limit population size • At the community level • An ecologist might focus on interspecies interactions

8. Ecosystem interactions involve • Living (biotic) communities and nonliving (abiotic) physical and chemical factors

9. Figure 34.2A THE BIOSPHERE • 34.2 The biosphere is the total of all of Earth’s ecosystems • The biosphere • Is the global ecosystem

10. Figure 34.2B • Patchiness of the environment • Characterizes the biosphere

11. CONNECTION • 34.3 Environmental problems reveal the limits of the biosphere • Human activities, including the widespread use of chemicals • Affect all parts of the biosphere

12. Figure 34.3 • Rachel Carson, a famous ecologist • Was one of the first people to perceive the global dangers of pesticide use

13. Figure 34.4 • 34.4 Physical and chemical factors influence life in the biosphere • Abiotic factors determining the biosphere’s structure and dynamics include • Solar energy, water, temperature, wind, and disturbances

14. Figure 34.5 • 34.5 Organisms are adapted to abiotic and biotic factors by natural selection • Unique adaptations • Allow the survival of organisms in particular habitats

15. Biotic factors, such as predation and competition • Can lead to the evolution of adaptations by natural selection

16. North Pole60ºN Low angle ofincoming sunlight 30ºNTropic ofCancer Sunlight strikesmost directly 0º (equator) Tropic ofCapricorn30ºS Low angle of incoming sunlight 60ºSSouth Pole Atmosphere • 34.6 Regional climate influences the distribution of biological communities • Most climatic variations • Are due to the uneven heating of Earth’s surface as it orbits the sun Figure 34.6A

17. The tilt of the Earth’s axis • Causes the changes of the seasons in the northern and southern hemispheres March equinox(equator facessun directly) June solstice(NorthernHemisphere tiltstoward sun) Constant tiltof 23.5º Decembersolstice(NorthernHemisphere tiltsaway from sun) Septemberequinox Figure 34.6B

18. 60ºN Descendingdry airabsorbsmoisture Descendingdry airabsorbsmoisture 30ºN Ascendingmoist airreleasesmoisture Trade winds Trade winds Doldrums 0º 23.5º 23.5º 30º 30º 30ºS Temperatezone Temperatezone Tropics • The uneven heating of the Earth • Also sets up patterns of precipitation and prevailing winds Figure 34.6C, D

19. Fresno104º 40 miles DeathValley119º Paso Robles93º Bakersfield106º Pacific Ocean Burbank86º Santa Barbara 75º San Bernardino 101º Key Riverside 91º Los Angeles(Airport) 74º 70s (ºF) Santa Ana84º Palm Springs 104º 80s 90s 100s 110s San Diego 75º Figure 34.6E • Ocean currents • Influence coastal climate

20. Winddirection East PacificOcean SierraNevada CoastRange Figure 34.6F • Landforms such as mountains • Affect rainfall

21. AQUATIC BIOMES • 34.7 Oceans occupy most of Earth’s surface • Several characteristics shape ocean communities • Light, distance from shore, and the availability of nutrients

22. Figure 34.7A • The intertidal zone, an oceanic zone • Is the area of shore where the ocean meets the land

23. Intertidal zone 0 Photic zone 200 m Continentalshelf Pelagiczone Benthic zone(seafloor) Aphoticzone 2,500–6,000 m • Oceanic zones also include • The pelagic and benthic zones Figure 34.7B

24. Figure 34.7C • Coral reefs • Are found in warm waters above continental shelves

25. Figure 34.7D • Estuaries • Are productive areas where rivers flow into the ocean

26. 34.8 Freshwater biomes include lakes, ponds, rivers, streams, and wetlands • Factors that shape lake and pond communities include • Light, temperature, and the availability of nutrients and dissolved oxygen

27. Figure 34.8A • Abiotic factors change from the source of a river to its mouth • And communities vary accordingly

28. Figure 34.8B • Wetlands include • Marshes and swamps

29. TERRESTRIAL BIOMES • 34.9 Terrestrial biomes reflect regional variations in climate • Temperature and rainfall • Mainly determine the terrestrial biomes

30. 30ºN Tropic ofCancer Equator Tropic ofCapricorn 30ºS Temperate grassland Tropical forest High mountains Polar ice Savanna Temperate broadleaf forest Desert Coniferous forest Chaparral Tundra Figure 34.9 • Major terrestrial biomes

31. Figure 34.10 • 34.10 Tropical forests cluster near the equator • Tropical rain forests • Are the most diverse ecosystem

32. Figure 34.11 • 34.11 Savannas are grasslands with scattered trees • Savannas • Are dry and warm

33. Figure 34.12 • 34.12 Deserts are defined by their dryness • Deserts • Are the driest biomes

34. Figure 34.13 • 34.13 Spiny shrubs dominate the chaparral • The chaparral • Is a shrubland with cool, rainy winters and dry, hot summers

35. Figure 34.14 • 34.14 Temperate grasslands include the North American prairie • Temperate grasslands • Are found where winters are cold

36. Figure 34.15 • 34.15 Broadleaf trees dominate temperate forests • Temperate broadleaf forests grow throughout midlatitude regions • Where there is sufficient moisture to support the growth of large trees

37. Figure 34.16 • 34.16 Coniferous forests are often dominated by a few species of trees • The northern coniferous forest, or taiga • Is found where there are short summers, and long, snowy winters

38. Figure 34.17 • 34.17 Long, bitter-cold winters characterize the tundra • Arctic tundra • Is a treeless biome characterized by extreme cold, wind, and permafrost

39. Alpine tundra • Occurs above the treeline on high mountains

40. Figure 34.18A, B TALKING ABOUT SCIENCE • 34.18 Ecologist Ariel Lugo studies tropical forests in Puerto Rico • The Luquillo Experimental Forest • Allows ecologists to study the effects of disruption on tropical forests