Week 1 Introduction to Ecology and the Biosphere PDF

Chapter 52 An Introduction to Ecology and the Biosphere PowerPoint® Lecture Presentations for Biology Eighth Edition Neil Campbell and Jane Reece Lectures by Chris Romero, updated by Erin Barley with contributions from Joan Sharp Copyright © 2008 Pearson Education, Inc., publis...

Chapter 52 An Introduction to Ecology and the Biosphere PowerPoint® Lecture Presentations for Biology Eighth Edition Neil Campbell and Jane Reece Lectures by Chris Romero, updated by Erin Barley with contributions from Joan Sharp Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Overview: The Scope of Ecology Ecology is the scientific study of the interactions between organisms and the environment These interactions determine distribution of organisms and their abundance Ecology reveals the richness of the biosphere Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Scope of Ecological Research Ecologists work at levels ranging from individual organisms to the planet Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings  Organismal ecology studies how an organism’s structure, physiology, and (for animals) behavior meet environmental challenges Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-1 Fig. 52-2 Organismal ecology Population ecology Community ecology Ecosystem ecology Landscape ecology Global ecology Fig. 52-2a  A population is a group of individuals of the same species living in an area Population ecology focuses on factors affecting how many individuals of a species live in an area Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-2b  A community is a group of populations of different species in an area Community ecology deals with the whole array of interacting species in a community Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-2c  An ecosystem is the community of organisms in an area and the physical factors with which they interact Ecosystem ecology emphasizes energy flow and chemical cycling among the various biotic and abiotic components Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-2d  A landscape is a mosaic of connected ecosystems Landscape ecology deals with arrays of ecosystems and how they are arranged in a geographic region Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-2e  The biosphere is the global ecosystem, the sum of all the planet’s ecosystems Global ecology examines the influence of energy and materials on organisms across the biosphere Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Climate Four major abiotic components of climate are temperature, water, sunlight, and wind The long-term prevailing weather conditions in an area constitute its climate Macroclimate consists of patterns on the global, regional, and local level Microclimate consists of very fine patterns, such as those encountered by the community of organisms underneath a fallen log Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Global Climate Patterns Global climate patterns are determined largely by solar energy and the planet’s movement in space Sunlight intensity plays a major part in determining the Earth’s climate patterns More heat and light per unit of surface area reach the tropics than the high latitudes Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-10a Latitudinal Variation in Sunlight Intensity 90ºN (North Pole) 60ºN Low angle of incoming sunlight 30ºN 23.5ºN (Tropic of Cancer) Sun directly overhead at equinoxes 0º (equator) 23.5ºS (Tropic of Capricorn) 30ºS Low angle of incoming sunlight 60ºS 90ºS (South Pole) Atmosphere Seasonal Variation in Sunlight Intensity 60ºN 30ºN March equinox 0º (equator) June solstice 30ºS Constant tilt December solstice of 23.5º September equinox Fig. 52-10b 90ºN (North Pole) 60ºN Low angle of incoming sunlight 30ºN 23.5ºN (Tropic of Cancer) Sun directly overhead at equinoxes 0º (equator) 23.5ºS (Tropic of Capricorn) 30ºS Low angle of incoming sunlight 60ºS 90ºS (South Pole) Atmosphere Fig. 52-10c 60ºN 30ºN March equinox 0º (equator) June solstice 30ºS Constant tilt December solstice of 23.5º September equinox  Global air circulation and precipitation patterns play major roles in determining climate patterns Warm wet air flows from the tropics toward the poles Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-10d Global Air Circulation and Precipitation Patterns 60ºN 30ºN Descending Descending dry air dry air 0º (equator) absorbs absorbs Ascending moisture moisture moist air releases 30ºS moisture 60ºS 0º 30º 23.5º 23.5º 30º Arid Tropics Arid zone zone Global Wind Patterns 66.5ºN (Arctic Circle) 60ºN Westerlies 30ºN Northeast trades Doldrums 0º (equator) Southeast trades 30ºS Westerlies 60ºS 66.5ºS (Antarctic Circle) Fig. 52-10e 60ºN Descending Descending dry air dry air 30ºN absorbs absorbs moisture moisture 0º Ascending (equator) moist air releases 30ºS moisture 60ºS 30º 23.5º 0º 23.5º 30º Arid Tropics Arid zone zone  Air flowing close to Earth’s surface creates predictable global wind patterns Cooling trade winds blow from east to west in the tropics; prevailing westerlies blow from west to east in the temperate zones Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-10f 66.5ºN (Arctic Circle) 60ºN Westerlies 30ºN Northeast trades Doldrums 0º (equator) Southeast trades 30ºS Westerlies 60ºS 66.5ºS (Antarctic Circle) Regional, Local, and Seasonal Effects on Climate Proximity to bodies of water and topographic features contribute to local variations in climate Seasonal variation also influences climate Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Bodies of Water The Gulf Stream carries warm water from the equator to the North Atlantic Oceans and their currents and large lakes moderate the climate of nearby terrestrial environments Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-11 Labrador current Gulf stream Equator water rm Wa Cold water Fig. 52-12 2 Air cools at 3 Cooler high elevation. air sinks over water. 1 Warm air over land rises. 4 Cool air over water moves inland, replacing rising warm air over land. Mountains Mountains have a significant effect on – The amount of sunlight reaching an area – Local temperature – Rainfall Rising air releases moisture on the windward side of a peak and creates a “rain shadow” as it absorbs moisture on the leeward side Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-13 Leeward side Wind of mountain direction Mountain range Ocean Seasonality The angle of the sun leads to many seasonal changes in local environments Lakes are sensitive to seasonal temperature change and experience seasonal turnover Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Microclimate Microclimate is determined by fine-scale differences in the environment that affect light and wind patterns Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Long-Term Climate Change Global climate change will profoundly affect the biosphere One way to predict future global climate change is to study previous changes As glaciers began retreating 16,000 years ago, tree distribution patterns changed As climate changes, species that have difficulty dispersing may have smaller ranges or could become extinct Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-14 Current range Predicted range Overlap (a) 4.5ºC warming over (b) 6.5ºC warming over next century next century Concept 52.3: Aquatic biomes are diverse and dynamic systems that cover most of Earth Biomes are the major ecological associations that occupy broad geographic regions of land or water Varying combinations of biotic and abiotic factors determine the nature of biomes Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings  Aquatic biomes account for the largest part of the biosphere in terms of area They can contain fresh water or salt water (marine) Oceans cover about 75% of Earth’s surface and have an enormous impact on the biosphere Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-15 Lakes Coral reefs Rivers Oceanic pelagic and benthic zones Estuaries 30ºN Intertidal zones Tropic of Cancer Equator Tropic of Capricorn 30ºS Stratification of Aquatic Biomes Many aquatic biomes are stratified into zones or layers defined by light penetration, temperature, and depth Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-16 Intertidal zone Neritic zone Oceanic zone Littoral zone Limnetic 0 zone Photic zone 200 m Continental Pelagic shelf zone Benthic Aphotic Photic zone zone zone Pelagic Benthic zone zone Aphotic zone 2,000–6,000 m Abyssal zone (a) Zonation in a lake (b) Marine zonation Fig. 52-16a Littoral zone Limnetic zone Photic zone Pelagic Benthic zone zone Aphotic zone (a) Zonation in a lake Fig. 52-16b Intertidal zone Neritic zone Oceanic zone 0 Photic zone 200 m Continental Pelagic shelf zone Benthic Aphotic zone zone 2,000–6,000 m Abyssal zone (b) Marine zonation  The upper photic zone has sufficient light for photosynthesis while the lower aphotic zone receives little light The organic and inorganic sediment at the bottom of all aquatic zones is called the benthic zone The communities of organisms in the benthic zone are collectively called the benthos Detritus, dead organic matter, falls from the productive surface water and is an important source of food Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings  The most extensive part of the ocean is the abyssal zone with a depth of 2,000 to 6,000 m Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings  In oceans and most lakes, a temperature boundary called the thermocline separates the warm upper layer from the cold deeper water Many lakes undergo a semiannual mixing of their waters called turnover Turnover mixes oxygenated water from the surface with nutrient-rich water from the bottom Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-17-1 Winter 0º 2º 4º 4º 4º 4ºC Fig. 52-17-2 Spring 4º 4º 4º 4º 4º 4ºC Fig. 52-17-3 Summer 22º 20º 18º 8º 6º 5º 4ºC Thermocline Fig. 52-17-4 Autumn 4º 4º 4º 4º 4º 4ºC Fig. 52-17-5 Winter Spring Summer Autumn 0º 4º 22º 4º 2º 4º 20º 4º 4º 4º 18º 4º 4º 4º 8º 4º 6º 4º 4º 4º 5º 4ºC 4ºC 4ºC 4ºC Thermocline Aquatic Biomes Major aquatic biomes can be characterized by their physical environment, chemical environment, geological features, photosynthetic organisms, and heterotrophs Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Lakes Oligotrophic lakes are nutrient-poor and generally oxygen-rich Eutrophic lakes are nutrient-rich and often depleted of oxygen if ice covered in winter Rooted and floating aquatic plants live in the shallow and well-lighted littoral zone Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings  Water is too deep in the limnetic zone to support rooted aquatic plants; small drifting animals called zooplankton graze on the phytoplankton Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-18a An oligotrophic lake in Grand Teton National Park, Wyoming Fig. 52-18b A eutrophic lake in the Okavango Delta, Botswana Wetlands A wetland is a habitat that is inundated by water at least some of the time and that supports plants adapted to water-saturated soil Wetlands can develop in shallow basins, along flooded river banks, or on the coasts of large lakes and seas Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings  Wetlands are among the most productive biomes on earth and are home to diverse invertebrates and birds Video: Swans Taking Flight Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-18c Okefenokee National Wetland Reserve in Georgia Streams and Rivers The most prominent physical characteristic of streams and rivers is current A diversity of fishes and invertebrates inhabit unpolluted rivers and streams Damming and flood control impair natural functioning of stream and river ecosystems Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-18d A headwater stream in the Great Smoky Mountains Fig. 52-18e The Mississippi River far from its headwaters Estuaries An estuary is a transition area between river and sea Salinity varies with the rise and fall of the tides Estuaries are nutrient rich and highly productive An abundant supply of food attracts marine invertebrates and fish Video: Flapping Geese Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-18f An estuary in a low coastal plain of Georgia Intertidal Zones An intertidal zone is periodically submerged and exposed by the tides Intertidal organisms are challenged by variations in temperature and salinity and by the mechanical forces of wave action Many animals of rocky intertidal environments have structural adaptations that enable them to attach to the hard substrate Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-18g Rocky intertidal zone on the Oregon coast Oceanic Pelagic Zone The oceanic pelagic biome is a vast realm of open blue water, constantly mixed by wind- driven oceanic currents This biome covers approximately 70% of Earth’s surface Phytoplankton and zooplankton are the dominant organisms in this biome; also found are free-swimming animals Video: Shark Eating a Seal Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-18h Open ocean off the island of Hawaii Coral Reefs Coral reefs are formed from the calcium carbonate skeletons of corals (phylum Cnidaria) Corals require a solid substrate for attachment Unicellular algae live within the tissues of the corals and form a mutualistic relationship that provides the corals with organic molecules Video: Coral Reef Video: Clownfish and Anemone Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-18i A coral reef in the Red Sea Marine Benthic Zone The marine benthic zone consists of the seafloor below the surface waters of the coastal, or neritic, zone and the offshore pelagic zone Organisms in the very deep benthic, or abyssal, zone are adapted to continuous cold and extremely high water pressure Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings  Unique assemblages of organisms are associated with deep-sea hydrothermal vents of volcanic origin on mid-oceanic ridges; here the autotrophs are chemoautotrophic prokaryotes Video: Hydrothermal Vent Video: Tubeworms Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-18j A deep-sea hydrothermal vent community Concept 52.4: The structure and distribution of terrestrial biomes are controlled by climate and disturbance Climate is very important in determining why terrestrial biomes are found in certain areas Biome patterns can be modified by disturbance such as a storm, fire, or human activity Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-19 Tropical forest Savanna Desert 30ºN Chaparral Tropic of Temperate Cancer grassland Equator Temperate Tropic of broadleaf forest Capricorn Northern 30ºS coniferous forest Tundra High mountains Polar ice Climate and Terrestrial Biomes Climate has a great impact on the distribution of organisms This can be illustrated with a climograph, a plot of the temperature and precipitation in a region Biomes are affected not just by average temperature and precipitation, but also by the pattern of temperature and precipitation through the year Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-20 Desert Temperate grassland Tropical forest 30 Annual mean temperature (ºC) Temperate 15 broadleaf forest Northern coniferous 0 forest Arctic and alpine tundra –15 0 100 200 300 400 Annual mean precipitation (cm) General Features of Terrestrial Biomes and the Role of Disturbance Terrestrial biomes are often named for major physical or climatic factors and for vegetation Terrestrial biomes usually grade into each other, without sharp boundaries The area of intergradation, called an ecotone, may be wide or narrow Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings  Vertical layering is an important feature of terrestrial biomes, and in a forest it might consist of an upper canopy, low-tree layer, shrub understory, ground layer of herbaceous plants, forest floor, and root layer Layering of vegetation in all biomes provides diverse habitats for animals Biomes are dynamic and usually exhibit extensive patchiness Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Terrestrial Biomes Terrestrial biomes can be characterized by distribution, precipitation, temperature, plants, and animals Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Tropical Forest In tropical rain forests, rainfall is relatively constant, while in tropical dry forests precipitation is highly seasonal Tropical forests are vertically layered and competition for light is intense Tropical forests are home to millions of animal species, including an estimated 5–30 million still undescribed species of insects, spiders, and other arthropods Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-21a A tropical rain forest in Borneo Desert Precipitation is low and highly variable, generally less than 30 cm per year; deserts may be hot or cold Desert plants are adapted for heat and desiccation tolerance, water storage, and reduced leaf surface area Common desert animals include many kinds of snakes and lizards, scorpions, ants, beetles, migratory and resident birds, and seed-eating rodents; many are nocturnal Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-21b A desert in the southwestern United States Savanna Savanna precipitation and temperature are seasonal Grasses and forbs make up most of the ground cover Common inhabitants include insects and mammals such as wildebeests, zebras, lions, and hyenas Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-21c A savanna in Kenya Chaparral Chaparral climate is highly seasonal, with cool and rainy winters and hot dry summers The chaparral is dominated by shrubs, small trees, grasses, and herbs; many plants are adapted to fire and drought Animals include amphibians, birds and other reptiles, insects, small mammals and browsing mammals Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-21d An area of chaparral in California Temperate Grassland Temperate grasslands are found on many continents Winters are cold and dry, while summers are wet and hot The dominant plants, grasses and forbs, are adapted to droughts and fire Native mammals include large grazers and small burrowers Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-21e Sheyenne National Grassland in North Dakota Northern Coniferous Forest The northern coniferous forest, or taiga, extends across northern North America and Eurasia and is the largest terrestrial biome on Earth Winters are cold and long while summers may be hot Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings  The conical shape of conifers prevents too much snow from accumulating and breaking their branches Animals include migratory and resident birds, and large mammals Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-21f Rocky Mountain National Park in Colorado Temperate Broadleaf Forest Winters are cool, while summers are hot and humid; significant precipitation falls year round as rain and snow A mature temperate broadleaf forest has vertical layers dominated by deciduous trees in the Northern Hemisphere and evergreen eucalyptus in Australia Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings  Mammals, birds, and insects make use of all vertical layers in the forest In the Northern Hemisphere, many mammals hibernate in the winter Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-21g Great Smoky Mountains National Park in North Carolina Tundra Tundra covers expansive areas of the Arctic; alpine tundra exists on high mountaintops at all latitudes Winters are long and cold while summers are relatively cool; precipitation varies Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings  Permafrost, a permanently frozen layer of soil, prevents water infiltration Vegetation is herbaceous (mosses, grasses, forbs, dwarf shrubs and trees, and lichen) and supports birds, grazers, and their predators Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Fig. 52-21h Denali National Park, Alaska, in autumn Fig. 52-UN1 Why is species X absent from an area? Yes Area inaccessible or Does dispersal limit its distribution? insufficient time No Yes Does behavior limit its distribution? Habitat selection No Do biotic factors (other species) Yes Predation, parasitism, limit its distribution? competition, disease No Chemical factors Water, oxygen, salinity, pH, soil nutrients, etc. Do abiotic factors limit its distribution? Temperature, light, soil Physical structure, fire, moisture, etc. factors Fig. 52-T1 Fig. 52-UN2 100 Mean height (cm) 50 0 Altitude (m) 3,000 2,000 Sierra Nevada 1,000 Great Basin Plateau 0 Seed collection sites Fig. 52-UN3