A great deal of this topic revolves around the concept of SUSTAINABILITY

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3 A great deal of this topic revolves around the concept of SUSTAINABILITY Here s a good short introduction to what sustainability means. 2:00 What can you do at home to make our world more sustainable?

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5 Introduction to biodiversity Conservation biology is a goal-oriented science that seeks to counter the biodiversity crisis, the current rapid decrease in Earth s variety of life. Extinction is a natural phenomenon that has been occurring since life evolved on earth. The current rate of extinction is what underlies the biodiversity crisis. A high rate of species extinction is being caused by humans. Watch where you step. 3:30

6 Personal Grooming Products and Great Lakes Marine Life Could removing dead skin cells from your face each night mean doom for perch and other Great Lakes species? Cosmetics manufacturers use these micro beads as abrasives in facial and body scrubs. They are too tiny for water treatment plants to filter, so they wash down the drain and into the Great Lakes. The biggest worry: fish or turtles or seagulls think of them as dinner; when eaten, the inert beads can deprive animals of nutrients from real food or lodge in their gut, blocking digestive systems. What would this do to a food web?

7 1. The three levels of biodiversity are genetic diversity, species diversity, and ecosystem diversity Fig. 55.1

8 Loss of species diversity. Much of the discussion of the biodiversity crisis centers on species diversity. The U.S. Endangered Species Act (ESA) defines an endangered species as one in danger of extinction throughout its range, and a threatened species as those likely to become endangered in the foreseeable future.

9 Here are a few examples of why conservation biologists are concerned about species loss. The IUCN reports that 13% of the known 9,040 bird species are threatened with extinction. That is 1,183 species!!! The Center for Plant Conservation estimates that 200 of the 20,000 known plant species in the U. S. have become extinct since records have been kept, and another 730 are endangered or threatened. About 20% of the known freshwater species of fish in the world have become extinct or are seriously threatened.

10 Loss of ecosystem diversity. The local extinction of one species, like a keystone predator, can affect an entire community. Some ecosystems are being erased from the Earth at an unbelievable pace. For example, an area the size of the state of West Virginia is lost from tropical forests each year.

11 Biodiversity is a crucial natural resource, and species that are threatened could provide crops, fibers, and medicines for human use. The loss of species also means the loss of genes. Fig Biodiversity represents the sum of all the genomes on Earth. Loss of genes = less adaptable.

12 3. The four major threats to biodiversity are habitat destruction, introduced species, overexploitation and food chain disruption Habitat destruction. By catastrophes or humans. Human alteration of habitat is the single greatest cause of habitat destruction, responsible for 73% of species designated extinct, endangered, or rare. About 93% of the world s coral reefs have been damaged by humans. Watch the Bleaching4:00 How does cutting down a forest affect global warming?

13 Production in Freshwater Ecosystems. Solar radiation and temperature are closely linked to primary production in freshwater lakes, something the EOC wants you to remember. During the 1970s, sewage and fertilizer pollution added nutrients like nitrates, to lakes, which shifted many lakes from having phytoplankton communities to those dominated by diatoms and green algae. We ve cleaned a lot of this up, but it continues to be a problem.

14 This process is called eutrophication, and has undesirable impacts from a human perspective. Hey, how about explaining that to us.

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16 Hypoxic/anoxic zone in the Gulf of Mexico

17 Another big issue plastic in the ocean See here what you will find in the middle of the ocean. 1:30

18 Fig

19 The carbon cycle fits the generalized scheme of biogeochemical cycles better than water. Fig

20 But the water cycle and the carbon cycle are linked in many ways, including those that we impact. Fig

21 2. Combustion of fossil fuels is the main cause of acid precipitation The burning of fossil fuels releases sulfur and nitrogen oxides that react with water in the atmosphere to produce sulfuric and nitric acids. Fig a

22 These acids fall back to earth as acid precipitation, damaging ecosystems greatly. The acids can kill plants, and can kill aquatic organisms by changing the ph of the soil and water. Fig b

23 4. Human activities may be causing climate change by increasing carbon dioxide concentration in the atmosphere Rising atmospheric CO 2. Since the Industrial Revolution, the concentration of CO 2 in the atmosphere has increased greatly as a result of burning fossil fuels. Normally, this carbon would stay locked up in coal and oil for a long time. Affects Carbon AND Water cycles. Let s pick apart a video. 5 min.

24 Measurements in 1958 read 316 ppm and increased to 400 ppm in May 2013, highest in a few million years Fig

25 The greenhouse effect. Rising levels of atmospheric CO 2 and methane may have an impact on Earth s heat budget. When light energy hits the Earth, much of it is reflected off the surface. CO 2, methane and other gases cause the Earth to retain some of the energy that would ordinarily escape the atmosphere. This phenomenon is the greenhouse effect. The Earth needs this heat, but too much could be disastrous. Watch the methane in Siberia.

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27 Global warming. How will increasing levels of CO 2 in the atmosphere affect Earth? A doubling of CO 2 will cause a 2º C increase in the average temperature of Earth. Rising temperatures can cause polar ice cap melting, which can flood coastal areas. The distribution of organisms has already started to change. Ash borers kill baseball bats! It is important that humans attempt to stabilize their use of fossil fuels.

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29 But here will be the biggest problem with carbon dioxide increase Ocean acidification. 2 min. If sea level rises you can move to a different place. If food chains collapse, you can t move to a different food chain. Once again both Carbon AND water cycles are affected.

30 5. Human activities are depleting the atmospheric ozone Life on earth is protected from the damaging affects of ultraviolet radiation (UV) by a layer of O 3, or ozone. Studies suggest that the ozone layer has been gradually thinning since Fig a

31 The destruction of ozone probably results from the accumulation of chlorofluorocarbons, chemicals used in refrigeration and aerosol cans, and in certain manufacturing processes. The result of a reduction in the ozone layer may be increased levels of UV radiation that reach the surface of the Earth. This radiation has been linked to skin cancer and cataracts. So ozone up high is good, down low bad. But when it traps UV radiation, ozone up high also contributes to global warming!

32 Introduced (aka exotic, invasive) species. Introduced species are those that humans move from native locations to new geographic regions. The Nile perch was introduced into Lake Victoria as a food fish, but led to the extinction of several native species. Pythons? Fig. 57.7a

33 Overexploitation. This refers to the human harvesting of wild plants and animals at rates that exceed the ability of those populations to rebound. The great auk was overhunted and became extinct. Fig. 55.8

34 The African elephant has been overhunted and the populations have declined dramatically. The bluefin tuna is another example of an overharvested species. Fig. 55.9

35 3. Conserving species involves weighing conflicting demands Conservation biology highlights the relationship between science, technology and society. High profile organisms may be the most popular due to use as resources. Questions about human habitat needs also arise. The ecological role of the organisms must be addressed as well. And then there is the economy. Decisions must weigh the costs and benefits. EOC!

36 4. Restoring degraded areas is an increasingly important conservation effort Restoration ecology applies ecological principles in developing ways to return degraded areas to natural conditions. Biological communities can recover from many types of disturbances, through a series of restoration mechanisms that occur during ecological succession.

37 Fig

38 Bioremediation is the use of living organisms to detoxify polluted ecosystems. Restoration ecologists use various types of organisms, like plants that absorb heavy metals, to remove many different types of toxins from ecosystems. Fig

39 The impact of human activity on the ozone layer is one more example of how much we are able to disrupt ecosystems and the entire biosphere. Are we entering the Anthropocene Era? 18 minutes if time. So what to do??? (9 min.)

40 What does it all add up to? Too many people on earth for the amount of resources each person uses. It can be measured by how much fossil fuel has to be burnt for you to live the life you do. This is called your carbon footprint. Let s calculate here. Now some practice questions

41 Which of the following is NOT an example of sustainable development? A. Using one insect to control another that is consuming crops B. Planting crops that will grow in the shade to reduce deforestation C. Installing solar power cells to reduce the need to burn fossil fuels D. Using the slash-and-burn technique to clear land for farming

42 To reduce the use of fossil fuels, automobile makers are producing electric cars. Which of the following is an advantage of using cars that run on electricity instead of gasoline? A. Electric cars use batteries that are easy to recharge B. Electric cars cost less than gasoline-powered cars C. Electric cars do not release pollutants into the environment D. Electric cars are easier to operate than gasolinepowered cars

43 Which of these is the best reason for using wind farms to produce electrical power? A. The use of wind farms makes electricity less expensive B. The use of wind farms conserves nonrenewable fuels C. Wind farms have little environmental impact D. Wind farms are suitable for most locations

44 A power company wants to build a new electric power plant next to a river and use water from the river for cooling. Which of the following should be studied before deciding whether to let the company build the plant? A. The price of the high-voltage wires used to transmit electricity B. The effects of warmer water on the fish species that live in the river C. The power company s contributions to support local sports teams D. The efficiency of the generators that the company plans to build

45 Human activities that increase carbon dioxide in the atmosphere are likely to cause which of the following environmental changes? A. Tsunamis B. Decreased plant growth C. An ice age D. A higher sea level