Chapter 1 Introduction to Environmental Science: Studying the State of Our Earth

Transcription

1 Chapter 1 Introduction to Environmental Science: Studying the State of Our Earth Friedland and Relyea Environmental Science for AP, second edition 2015 W.H. Freeman and Company/BFW AP is a trademark registered and/or owned by the College Board, which was not involved in the production of, and does not endorse, this product.

2 Module 1 Environmental Science

3 APES Underlying Concepts for Environmental Science Science is a process Energy Conversions underlie all ecological processes The Earth itself is one interconnected system Humans alter natural systems Environmental problems have a cultural and social context Human survival depends upon developing practices that will achieve sustainibility

4 Human Interactions Current Human Population 7.4 billion 220,000 ppd net increase in population 1.5 million per week 80 million per year

5 Ecology Basic Terms AP Environmental Science

6 Ecology The study (or the science) of the interactions between organisms and their environment. Environmental Science looks specifically at the interactions between HUMANS and their environment

7 Environment The total conditions affecting an organism. Conditions are both living (biotic) and non-living (abiotic). Biotic factors include other organisms. Abiotic factors include matter (chemicals) and energy. We generally think of environment as being around an organism (Habitat). We will shortly come to realize that aspects of the environment are also inside or within organisms.

8 Organism Any living entity. There are five categories of living entities on Earth. Bacteria and Cyanobacteria (Kingdom Monera) Single-celled eukaryotic organisms (e.g. protozoa, amoebas, diatoms etc )(Kingdom Protista) Fungi (Kingdom Fungi) Plants (Kingdom Plantae) Animals (Kingdom Anamalia)

9 Life Life on Earth has the following characteristics. The cell is the basic unit of life. Organisms can be single-celled or multi-celled. Life forms have internal structure and organization. They have unique genetic material (DNA) in each cell. They acquire and transform matter and energy from the environment. They return matter and energy to the environment. They reproduce and adapt (overtime) to their surroundings.

10 Life Life can also be categorized into different levels Organism (one individual) Species (a specific type of individual organisms) Populations (how many?) Communities Ecosystem (Biome) 1. biosphere

11 Life Producers autotrophs meaning they produce their own food, the basis of every food chain/web. (plants, algae, bacteria) Consumers herbivores, carnivores, omnivores. Decomposers bacteria, fungi

12 Biosphere The thin zone at the surface of the Earth where life exists. The Biosphere extends a few miles above sea level into the atmosphere and up the slopes of the highest mountains. It extends a few miles below sea level into the deepest ocean trenches.

13 Ecosystem (You will need to know this definition by heart) A unit of biological organization consisting of organisms and communities of organisms interacting with their environment in such a way that energy flow (through the system) results in trophic structure and nutrient cycling. Ecosystems are self-sustaining under undisturbed conditions.

14 Carrying capacity The largest population that an environment can support. Depends upon: Availability of resources How easily matter and energy can be transferred between life-forms and the environment in that ecosystem.

15 World views One's core values and beliefs about: How the world works. What one s role in the world should be. A SENSE OF PLACE

16 DOMINANT WORLD VIEW - anthropocentric Humans are superior to other organisms on the planet. Nature = Resources Resources are unlimited Competition is the rule Survival of the fittest (Darwin misquoted) Knowledge based Growth is good

17 Eco-centric view Humans are cool but. Bacteria promote, sustain, maintain life. Biological diversity sustains ecosystems Nature = KIN Are we part or separate from the environment? All living things have connections. Environment Some resources are limited, some are not.

18 Eco-centric Survival of the Fit-ins More organisms are produced than can survive. Therefore those that are best adapted will survive. Realization that we don t know everything Not sure, open to suggestion, new understanding.

19 Eco-centric Sufficient/sustainable nature Perpetual growth is the mentality of a cancer cell. Science and Technology are value laden Community standards, religious views & personal philosophies. SENSE OF PLACE

20 Credits Fred Montague, Environment Notebook, p. 60, Mountain Bear Ink, 2003

21 Module 2 Environmental Indicators and Sustainability

22 Environmental Indicators

23 Biodiversity Levels of biodiversity. Biodiversity exists at three scales. (a) Ecosystem diversity is the variety of ecosystems within a region. (b) Species diversity is the variety of species within an ecosystem. (c) Genetic diversity is the variety of genes among individuals of a species.

24 Species Diversity Species A group of organisms that is distinct form other groups in its morphology (body form and structure), behavior, or biochemical properties. Species diversity The number of species in a region or in a particular type of habitat. Speciation The evolution of new species. Background extinction rate The average rate at which species become extinct over the long term.

25 Ecosystem Diversity Ecosystem diversity is a measure of the diversity of ecosystems or habitats that exist in a given region.

26 Food Production Key Global Environmental Indicator 2: Food Production Food production is our ability to grow food to nourish the human population. We use science and technology to increase the amount of food we can produce on a given area of land.

27 Food Production World grain production per person. Grain production has increased since the 1950s, but it has recently begun to level off.

28 Surface Temperature and CO 2 Concentration Key Global Environmental Indicator 3: Average Global Surface Temperature and CO 2 Concentration Greenhouse gases Gases in Earth's atmosphere that trap heat near the surface. The most significant greenhouse gas is carbon dioxide (CO 2 ). Anthropogenic Derived from human activities.

29 Surface Temperature and CO 2 Concentration The Earth-surface energy balance. Earth s surface is warmed by the Sun, radiating heat outward. Heat-trapping gases absorb the outgoing heat, reradiating some back to Earth.

30 Surface Temperature and CO 2 Concentration Changes in average global surface temperature and atmospheric CO 2 concentrations. Earth s average global surface temperature has increased steadily for at least the past 100 years.

31 Human Population Key Global Environmental Indicator 4: Human Population The current human population is 7.4 billion and growing. (220,000 people per day net increase) Population scientists project the human population will reach billion by 2050 and stabilize between billion by 2100.

32 Resource Depletion Key Global Environmental Indicator 5: Resource Depletion Some natural resources, for example, coal, oil, and uranium are finite and cannot be renewed or reused. Other natural resources, for example aluminum or copper, also exist in finite amounts but can be recycled. As the human population grows, it places greater demand on finite resources. Development Improvement in human well-being through economic advancement.

33 Patterns of Resource Consumption Resource use in developed and developing countries. Only 20 percent of the world s population lives in developed countries, but that 20 percent uses most of the world s resources. The remaining 80 percent of the population lives in developing countries and uses far fewer resources per capita.

34 Human well-being depends on sustainable practice Sustainability Living on Earth in a way that allows humans to use its resources without depriving future generations of those resources. Sustainable development Development that balances current well-being and economic advancement with resource management for the benefit of future generations.

35 Sustainable Practices Environmental systems must not be damaged beyond their ability to recover. Renewable resources must not be depleted faster than they can regenerate. Nonrenewable resources must be used sparingly. Biophilia Love of life.

36 The Ecological Footprint Ecological footprint A measure of how much an individual consumes, expressed in an area of land. The ecological footprint. Some of the many factors that go into the calculation of the footprint are shown here.

37 Module 3 Scientific Method

38 Science A Way of Knowing about the Universe around you!

39 Science A way of knowing How do people make sense of the world? Mythology Religion Democratic and consensus methods Dictatorial methods Common sense explanations Scientific explanations

40 Science a way of knowing What is Science? Science is a human endeavor that strives to explain natural phenomena through systematic observation and experimentation that provide repeatable empirical evidence from which hypotheses (possible explanations) can be formulated.

41 Science Science assumes the following: Humans can observe the natural world with their senses. Nature functions according to basic laws and principles. Phenomena have material (not supernatural) causes. Events and actions cause other events and actions. Through observation, experimentation, and reason, humans can discover and understand the basic laws and principles of nature.

42 Science Science as a process: (What we do.) a process of inquiry, discovery, observation, analysis, verification and communication. (Think scientific Method) Science as a product: An ever expanding body of information and knowledge. (Explanations about how the Universe works.)

43 Science Methods: Science Systematic observation and/or experimentation Formulation of tentative explanations (Hypotheses) Tests to prove or disprove the Hypothesis using designed experiments, natural experiments, systematic observations, comparisons, etc. Analysis of the tests followed by refinement, confirmation or rejection of the hypothesis. Communication of the results Independent evaluation, experimentation, and application by other scientists.

44 Scientific Method The scientific method. In an actual investigation, a researcher might reject a hypothesis and investigate further with a new hypothesis, several times if necessary, depending on the results of the experiment.

45 Controlled Experiments A typical experimental process. An investigation of the effects of chlorpyrifos on the central nervous system illustrates how the scientific method is used.

46 Science Kinds of Science Traditional, Mainstream Science Break-through Science ( frontier, cutting edge, revolutionary) Advocacy Science Secret Science

47 Science Limits of Science Possibilities for error in the scientific process (human, limits of instruments and methods) Science cannot help with some issues. Ethics, right vs wrong, good vs. evil Science does not prove Hypotheses or Theories absolutely. (tentative nature of science) Theories and Hypotheses become more reliable and more widely accepted as more evidence accumulates.

48 Hypotheses Tentative explanation of how the universe works. As new evidence is accumulated, knowledge & understanding change. New hypotheses and theories are developed

49 Theoretical Landscape of Science

50 Hypothesis Hypothesis A testable conjecture about how something works Null hypothesis A prediction that there is no difference between groups or conditions, or a statement or idea that can be falsified, or proven wrong.

51 Collect Data Replication The data collection procedure of taking repeated measurements. Sample size (n) The number of times a measurement is replicated in data collection. Accuracy How close a measured value is to the actual or true value. Precision How close the repeated measurements of a sample are to one another. Uncertainty An estimate of how much a measured or calculated value differs from a true value.

52 Collect Data Accuracy and precision. Accuracy refers to how close a measured value is to the actual or true value. Precision is how close repeated measurements of the same sample are to one another.

53 Interpret Results Once results have been obtained, analysis of the data begins. This process involves two types of reasoning, inductive and deductive. Inductive reasoning is the process of making general statements from specific facts or examples. Deductive reasoning is the process of applying a general statement to specific facts or situations. Scientists maintain multiple working hypotheses. Scientists reject or accept a hypothesis based on what the data show and begin to generate conclusions based on their results.

54 Disseminate Findings Scientists present papers at conferences and publish the results of their investigations. This allows other scientists to repeat the original experiment and verify or challenge the results. This can lead to a hypothesis eventually becoming a theory. Theory A hypothesis that has been repeatedly tested and confirmed by multiple groups of researchers and has reached wide acceptance.

55 Controlled Experiments Controlled experiments take place in a laboratory. Control group In a scientific investigation, a group that experiences exactly the same conditions as the experimental group, except for the single variable under study.

56 Natural Experiments Natural experiment A natural event that acts as an experimental treatment in an ecosystem.

57 Environmental Science Presents Unique Challenges There is no control planet with which we can compare Earth. It is difficult to determine what is better or worse for the environment. Environmental science has so many interacting parts, it is not easy to apply one system to another. When people are unable to meet their basic needs, they are less likely to be interested in protecting the environment.

58 Environmental Problems

59 Environmental Problems

60 Credits Fred Montague, Environment Notebook, Mountain Bear Ink, 2003