Chapter 12: Ecology Presentation PDF

Chapter 12: Ecology © 2017 Pearson Education, Inc.  12.1 Ecology is the study of organisms in their environments. Ecology is the study of how organisms interact with each other and with their environment. Ecologists make verifiable Hypothesis-driven ecolo...

Chapter 12: Ecology © 2017 Pearson Education, Inc.  12.1 Ecology is the study of organisms in their environments. Ecology is the study of how organisms interact with each other and with their environment. Ecologists make verifiable Hypothesis-driven ecology observations using the science may be conducted discovery approach. in the field or in the lab. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.1 Ecology can inform the philosophy and social movement of environmentalism. Ecology is distinct from environmentalism, a broad philosophy and social movement that seeks to maintain environmental quality. The science of ecology provides the basis for understanding environmental problems. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.1 Ecosystems provide valuable goods and services that benefit human society. Raw Erosion materials control estimated estimated value: value: >$2 >$16 trillion trillion Water Recreation treatment estimated and value: filtration >$20 estimated trillion value: >$22 © 2017 Pearson Education, Inc. trillion Chapter Table of Contents  12.1 Some important services are more difficult to quantify in monetary terms. Intrinsic Sustain value and define cultures Scientific Resources research for teaching and learning © 2017 Pearson Education, Inc. Chapter Table of Contents  12.2 Ecology can be studied at many levels. Organismal ecology Ecology is the scientific study of Population organisms in their ecology environments. It is convenient to Community divide ecology ecology into five Ecosystem increasingly ecology comprehensive Global levels. ecology © 2017 Pearson Education, Inc. Chapter Table of Contents  12.2 Ecology can be studied at many levels: organismal ecology. Organismal ecology focuses on the ways that organisms adapt to their environments through physiology and behavior. What type of questions might an organismal An organism is an ecologist ask? individual living being. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.2 Ecology can be studied at many levels: population ecology. Population ecology is concerned with the factors that affect population size, growth, and density. A population is a group What type of questions might a of individuals of the same population ecologist species living in the same ask? place at the same time. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.2 Ecology can be studied at many levels: community ecology. Questions in community ecology focus on interactions among species. A community consists What type of questions might a of all the populations (of community ecologist multiple species) living ask? in a particular place. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.2 Ecology can be studied at many levels: ecosystem ecology. Ecosystem ecology is concerned with questions of energy flow and chemical cycling. An ecosystem is all the What type of questions might an life living in a particular ecosystem ecologist area together with all the ask? nonliving components. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.2 All organisms interact with each other and the nonliving ecosystems The ecosystem includes all living organisms as well as nonliving factors such as air, sunlight, wind, and water. The dynamics of every ecosystem depend on two main processes: 1. E​ nergy flow 2. ​Chemical cycling © 2017 Pearson Education, Inc. Chapter Table of Contents  12.2 Energy flows through ecosystems. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.2 Chemicals cycle through ecosystems: © 2017 Pearson Education, Inc. Chapter Table of Contents  12.2 Ecology can be studied at many levels: ecology of the biosphere. At a global scale, ecologists can study the influence of energy and matter on organisms across the biosphere. What type of questions The biosphere is the might an ecologist ask global ecosystem. about the biosphere? © 2017 Pearson Education, Inc. Chapter Table of Contents  12.3 The biosphere includes biotic and abiotic factors. The living organisms of an ecosystem constitute its biotic factors. The abiotic factors of an ecosystem are its nonliving components. Abiotic factors can have a profound effect on the life within an ecosystem. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.3 Examples of abiotic factors include the supply of energy and nutrients. The most important abiotic factor is energy. – Most ecosystems on Earth are powered by solar energy via sunlight. The availability of inorganic nutrients can impact plant growth. – Examples are nitrogen and phosphorous. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.3 Other important abiotic factors Wind Water availability Temperature Fire © 2017 Pearson Education, Inc. Chapter Table of Contents  12.7 Interactions between species play important roles in communities. Within a community, species interact with members as they compete for food, water, sunlight, or living space. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.7 Competition occurs when two or more species rely on similar limiting resources. Competition is mutually harmful. According to the competitive exclusion principle, if the resources required by two species are too similar, they cannot coexist. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.7 Mutualism is a form of interspecies interaction in which both species benefit. Mutualism is beneficial to both species. – It often occurs among species that are symbiotic, living in close physical association with one another, but not all symbiotic relationships are mutual. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.7 Some interactions are beneficial to one species and harmful to the other. Predation is an interaction in which a predator species kills and eats a prey species. Cheetah and impala Herbivory is the eating of plant parts by an animal. Barrel cactus © 2017 Pearson Education, Inc. Chapter Table of Contents  12.7 Some interactions are beneficial to one species and harmful to the other. A parasite lives on or in (but does not kill) a host, from which it obtains nutrients. Mouse flea Pathogens are disease-causing microorganisms. © 2017 Pearson Education, Inc. Chestnut blight Chapter Table of Contents  12.8 Food webs describe multiple trophic structures. Trophic structure describes the feeding relationships within a community. Food chains and food webs describe the transfer of organic material from one trophic level to the next. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.8 A food chain is a simplified description of one part of the trophic structure. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.8 A food web interconnects multiple food chains. A food web of a hypothetical forest community Arrows indicate energy transfer or “who eats whom.” © 2017 Pearson Education, Inc. Chapter Table of Contents  12.8 Many toxins cannot be digested and are passed from one tropic level to another. Biological magnification is the tendency of toxins to become concentrated in a food chain. Why are pregnant women told to limit their consumption of tuna and other predatory fish? © 2017 Pearson Education, Inc. Chapter Table of Contents  12.9 Which forest is more diverse? Consider these two forests: Are they equally diverse? Or would you consider one forest more diverse than the other? © 2017 Pearson Education, Inc. Chapter Table of Contents  12.9 Species diversity includes both species richness and abundance. Consider these two forests: Both forests have the same number of species, or species richness (four in this example). © 2017 Pearson Education, Inc. Chapter Table of Contents  12.9 Species diversity includes both species richness and abundance. Consider these two forests: However, the relative abundance, differs between the two communities. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.9 Keystone species can drive patterns of species richness and diversity. A keystone species is a species that has a disproportionately large effect on its environment relative to its abundance. Ecologists studying the Alaskan coast discovered that a decline in the sea otter population allowed sea urchins to quickly multiply. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.9 Communities are rarely static, and disturbance is followed by recolonization. Primary succession occurs when an area has been rendered virtually lifeless with no soil. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.9 Ecological disturbance often adds to the diversity of habitats and communities. Secondary succession occurs after a disturbance that kills much of the life in an area but leaves the soil intact. After a disturbance, an area will be reoccupied by a series of species. Ecological succession may take hundreds or thousands of years. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.10 Invasive species disrupt ecosystems as both predators and competitors. When non-native organisms are introduced to a community, they can spread rapidly, becoming an invasive species. Invasive species are now a leading cause of extinctions of local populations. Lionfish were introduced into the Caribbean and consumed other fish voraciously. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.10 Invasive species spread rapidly after being introduced to a new environment. Burmese pythons were set loose in Florida. Kudzu is a climbing vine, A rogue’s gallery of introduced to the southern U.S. invasive species © 2017 Pearson Education, Inc. Chapter Table of Contents  12.10 Once established, controlling invasive species can be very difficult. Ecologists may implement biological control, the intentional release of a natural enemy. The introduction of a stingless wasp has helped keep populations of the invasive borer in check. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.10 Biological control for invasive species can have unintended consequences. In Hawaii and the Caribbean, growers introduced the mongoose, a fierce hunter of rats. Unfortunately, the mongooses also decimated native reptiles, amphibians, and birds. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.11 Biodiversity is a general term for the variety of living things on Earth. Biodiversity includes: Genetic Species Ecological diversity diversity diversity © 2017 Pearson Education, Inc. Chapter Table of Contents  12.11 Genetic biodiversity refers to the collection of genes within a population. Severely reducing genetic variation makes the population less able to adapt to a changing environment. – Because virtually all the potatoes in the country were genetically identical, the Irish potato blight caused widespread crop failure and famine. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.11 Species biodiversity refers to the number of different species. Extinction is the irreversible loss of all populations of a species. Ecologists estimate that at the current rate half of all living plant and animal species will be extinct by the end of this century. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.11 Ecosystem biodiversity refers to the variety of ecosystems found on Earth. The degradation of ecosystems threatens ecosystem services, benefits that ecosystems provide to people such as: – Waste decomposition – Water cycling – Nutrient cycling – Food production – Recreation © 2017 Pearson Education, Inc. Chapter Table of Contents  12.11 Biodiversity benefits people and supports our society in many ways. Emu (Dromaius Rosy periwinkle Belize Barrier Reef novaehollandiae) (Catharanthus roseus) Biodiversity Nearly all of The economies provides our of both drugs are many countries current and derived depend on future food from natural wildlife crops. © 2017 Pearson Education, Inc. products. preserves and Chapter Table of Contents  12.11 Causes of biodiversity loss: habitat destruction Habitat destruction is the single greatest threat to biodiversity. – This includes destruction of habitat due to development, agriculture, forestry, mining, and dam construction. Brazilian rain forest being cleared for agricultural use © 2017 Pearson Education, Inc. Chapter Table of Contents  12.11 Causes of biodiversity loss: overharvesting Overharvesting species faster than they can naturally replenish leads to a loss of biodiversity. – This includes hunting, fishing, and logging. Overfishing has decimated the populations of many wild fish. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.11 Causes of biodiversity loss: invasive species Invasive species are an increasingly grave threat to biodiversity. – The invader may have no natural predators and can thus multiply unchecked, causing the extinction of competitors or prey species. Introduced to Guam, brown tree snakes have driven several bird species to extinction or near extinction. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.11 Causes of biodiversity loss: pollution Pollution of the air and water contributes to biodiversity loss at the local, regional, and global levels. The Deepwater Horizon oil rig explosion in 2010 released oil into the Gulf of Mexico. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.11 Causes of biodiversity loss: climate change Global climate change impacts biodiversity at both local and global scales. – Ecologists predict declining biodiversity due to changes in rainfall patterns, disruption of seasonal patterns, rising temperatures, and ocean acidification. Coral bleaching is a phenomenon that has been linked with the increase in water temperatures and ocean acidification. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.14 Energy flows through ecosystems from producers to consumers. Primary producers convert solar energy to chemical energy via photosynthesis. Primary consumers are herbivores that eat primary producers. Secondary consumers are carnivores that eat primary consumers. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.14 Energy flows through ecosystems along multiple levels of consumers. Tertiary consumers are top-level predators. – As trophic levels increase, less energy is available at each transfer. Decomposers are organisms that break down nonliving matter. – Death at any level sends energy to the decomposers. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.14 The trophic structure of an ecosystem describes the feeding relationships. Energy enters an TROPHIC LEVEL 4 ecosystem as Tertiary consumers sunlight. TROPHIC LEVEL 3 Secondary consumers TROPHIC LEVEL 2 Primary consumers TROPHIC LEVEL 1 Primary producers Decomposers break down nonliving matter. At each energy conversion heat is released. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.14 Different ecosystems have different rates of primary production. Biomass is the total amount of living material in an ecosystem. Primary production measures the rate at which solar energy is converted to biomass. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.14 As energy is passed from one trophic level to the next, most of it is lost as heat. From one trophic level to the next, only around 10% of the energy transfers. The cumulative loss of energy means that each level of trophic structure can support fewer organisms than the last. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.14 Energy availability can be visualized in an ecological pyramid. Secondary Consumers Primary Consumers Producers 20,000 calories of primary production can feed 10 vegetarians for one day or support one meat-eater for one day. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.15 Elements—such as carbon and nitrogen—cycle through the biosphere. Energy flows through ecosystems. Elements cycle through ecosystems. Elements move from abiotic reservoirs (nonliving) such as the air, soil, and water, to biotic components (living) of ecosystems in a biogeochemical cycle. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.15 Biogeochemical cycles occur both locally and globally. Abiotic reservoirs Biotic components − Includes the atmosphere, − Includes producers, rocks, and oceans consumers, and decomposers Geological processes contribute to the abiotic reservoirs. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.15 The carbon cycle is an example of a biogeochemical cycle. The carbon cycle is affected by human activities (shown in red), primarily the burning of fossil fuels, which releases trapped carbon into the atmosphere as CO2. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.15 The nitrogen cycle is an example of a biogeochemical cycle. Nitrogen is only available to living things after soil bacteria convert N 2 to compounds that plants can take up. Human effects on the nitrogen cycle are shown in red. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.15 True or false? True or false? The top of the food chain has the most energy because energy accumulates up the chain. True or false? Decomposers release some energy into the soil that is then cycled back to plants. True or false? The carbon cycle consists only of photosynthesis and respiration. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.16 All water on Earth is interconnected in a global water cycle. Precipitation transfers water from the atmosphere to the land. Conversely, evaporation from bodies of water and transpiration from plants move water from terrestrial sources to the atmosphere. Water erodes the land as it moves to the ocean. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.16 The global water cycle Over the oceans, the net movement of water is from the sea into the atmosphere. Over land, it is from the clouds down to the land. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.16 Fresh water, a valuable resource for human societies, is relatively rare The vast majority of water on Earth’s surface is found in the oceans. Less than 1% of the water on Earth is fresh water that humans can access! © 2017 Pearson Education, Inc. Chapter Table of Contents  12.17 What impact does our population have on other species? The global human population is now over 7.2 billion and still growing. How might the increasing human population impact other species populations? Explain using ecological concepts. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.17 Humans depend on Earth for survival, but we cause many ecological problems. Humans depend on the continued health of Earth’s ecosystems for our own survival, but we threaten the health of ecosystems in several ways. No part of the biosphere remains unchanged by the collective influence of over 7 billion humans. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.17 The average American uses resources at a higher rate than the world average. An ecological footprint is an estimate of the amount of land and water required to sustain one person. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.17 The average world citizen uses more resources than the planet can provide. What are some ways we can each reduce our ecological footprint? © 2017 Pearson Education, Inc. Chapter Table of Contents  12.17 Human impact: Forest destruction The primary cause of forest destruction is clearing for agriculture. Satellite images for one region of a South American rain forest © 2017 Pearson Education, Inc. Chapter Table of Contents  12.17 Human impact: Freshwater shortages Some regions of the world are already experiencing dire freshwater shortages, and the problem will probably get worse in the near future. Polluted creek in Orange Depleted water levels at County, California Arrowrock Dam, Idaho © 2017 Pearson Education, Inc. Chapter Table of Contents  12.17 Human impact: Declining species Endangered species are those with rapidly declining populations. An endangered hawksbill The Canada lynx is considered turtle with researcher a threatened species. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.18 Humans can work together to solve ecological problems. Conservation biology is a branch of ecology that seeks to investigate and reverse the loss of biodiversity. The field of restoration ecology uses ecological principles to help repair degraded areas. Conservation and restoration ecology are both expanding fields and are making significant progress. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.18 Identifying conservation priority areas can save much biodiversity. Biodiversity hot spots are relatively small areas with unusually high concentrations of endemic species and endangered species. Endemic species are only found in a relatively small geographic area. The ring-tailed lemur is endemic to the island of Madagascar. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.18 Conservation biologists recommend preserving habitat in biodiversity hot spots. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.18 When people are motivated to act, species recovery can be dramatic. Bald eagles declined dramatically in the lower 48 U.S. states due to habitat loss and environmental toxins, primarily DDT. Today, bald eagles have recovered to over 10,000 breeding pairs. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.18 Conservation biologists also aim to maintain ecosystem biodiversity. Fragmentation is the splitting of habitats that isolates small populations. Corridors can be used to connect habitat patches. A bridge in the Netherlands allows animals to access areas otherwise separated by a road. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.18 Restoration ecologists work to repair degraded habitats. This includes returning native species and bioremediation, the use of living organisms to detoxify polluted ecosystems. Workers plant sunflowers to naturally remove toxins from topsoil. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.18 A realistic goal for the future is promoting sustainable development. The goal of sustainable development is to maintain the productivity of Earth’s ecosystems indefinitely. – Sensible, science-driven policies can help us take corrective action now, while much hope remains. Education plays an important role in conserving our biosphere. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.19 The accumulation of greenhouse gases is causing global climate change. Greenhouse gases are airborne chemicals that capture and hold heat within Earth’s atmosphere. They include: – Carbon dioxide (CO2) – Methane (CH4) – Nitrous oxide (N2O) – Water (H2O) vapor © 2017 Pearson Education, Inc. Chapter Table of Contents  12.19 Global climate change: data on greenhouse gases Atmospheric levels are higher now than at any time in the past 800,000 years. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.19 Global climate change: data on global temperatures Since 1880, there has been an increase in global surface temperatures. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.19 Carbon dioxide is an important greenhouse gas produced by our activities. Power generation and industry contribute the most CO2 to the atmosphere. CO2 contribution from various human activities © 2017 Pearson Education, Inc. Chapter Table of Contents  12.19 Why is the Earth warming? We need to understand the greenhouse effect. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.19 Greenhouse gases act as an atmospheric blanket, trapping heat. The greenhouse effect is vital to life on Earth; without it, most of Earth’s surface would be too cold to support life. The more greenhouse gases there are in the atmosphere, the more heat is trapped. The overwhelming consensus among scientists is that the atmospheric accumulation of greenhouse gases from human activity is warming the Earth, causing global climate change. © 2017 Pearson Education, Inc. Chapter Table of Contents  12.19 Global climate change has many far-reaching effects on ecosystems. Ecosystem effects include: – Habitat change or loss (shifting ranges) – Polar melting (species loss) © 2017 Pearson Education, Inc. Chapter Table of Contents  12.19 Global climate change has many far-reaching effects that impact human life. – Coral bleaching (can mean the loss of entire reef ecosystems) – Increasing fires (result of earlier snow melt) © 2017 Pearson Education, Inc. 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