1. Human Effects on the Biosphere
Chapter 44
Human Effects on the Biosphere

2. 44.1 Why Are So Many Species Threatened of Endangered?
All over the world, humans are _______________ wildlife _________ with our _____________, factories, and farms
We also put species at __________
__________________________________
__________________ them
Introducing ________________ competitors
The rate of species extinctions is rising; many types of biomes are _____________

3. Why Are So Many Species Threatened of Endangered? (cont’d.)
A species is considered endangered when one or more of its _______________ have declined _____________________
Endangered species
A species that faces extinction in all or ____________________________
Threatened species
_____________________ to become endangered in the near future

4. Why Are So Many Species Threatened of Endangered? (cont’d.)
C Texas blind salamander.
A White abalone.
Figure 44.1 Examples of endangered species native to the United States. To learn more about these and other threatened and endangered species, visit the United States Fish and Wildlife Service’s endangered species website at
D Florida perforate reindeer lichen.
B Pyne’s ground plum.

5. Why Are So Many Species Threatened of Endangered? (cont’d.)
Human activities threaten other species by destroying or ____________________
Around the globe, _______________ of habitats by ______________, ____________, and _________________ are major contributors to species loss

6. 44.2 What Are the Effects of Desertification and Deforestation?
________________ occurs when ______________ or grazing removes plants and _____________ topsoil to ___________________
Fewer plants means less _____________; rainfall decreases
In a _____________________ cycle, drought encourages desertification, which ____________ drought

7. What Are the Effects of Desertification and Deforestation? (cont’d.)
Figure Dust storms, one outcome of desertification
A Dust cloud in the Great Plains during the 1930s.
B Dust blows across the Atlantic from North Africa.

8. What Are the Effects of Desertification and Deforestation? (cont’d.)
_____________________ continue to disappear at an ___________________
In addition to ______________ destruction of forest organisms, deforestation encourages _______________, and raises __________________ in hilly areas
Deforestation also affects ________________ – temperatures rise, and reduced transpiration results in less rainfall
Figure 43.2 Latitudinal variation in the intensity of sunlight at ground level.

9. What Are the Effects of Desertification and Deforestation? (cont’d.)
Forests take up and store huge amounts of _______________, so deforestation also contributes to global climate change
Deforested areas also become __________________
Experimental deforestation increased ______________ of essential soil nutrients such as ____________ (compared with undisturbed forest)

10. What Are the Effects of Desertification and Deforestation? (cont’d.)
Figure 44.3 Deforestation. Cropland that once was rainforest extends right up to the edge of Iguaçu national park, a World Heritage site that straddles the border between Brazil and Argentina.

11. ANIMATION: Hubbard Brook Experiment
Figure {Animated} Effect of experimental deforestation on nutrient losses from soil. After deforestation, calcium (Ca) levels in runoff increased sixfold (gray). An undisturbed plot in the same forest showed no increase during this time (green).
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12. 44.3 How Does Trash Degrade Habitats?
Buried in the ground (such as lead from batteries) can ________________ groundwater
____________ at sea (such as ___________) harms marine life
Plastic and other garbage that enters our _____________________ for many years
Avoid buying plastics, or be sure to ____________ or dispose of them properly

13. How Does Trash Degrade Habitats? (cont’d.)
Figure 44.5 Perils of plastic
A Juvenile sea lion with ring of discarded plastic around its neck. As the animal grows, the plastic will cut into its neck, causing a wound and impairing its ability to feed.
B Recently deceased Laysan albatross chick, dissected to reveal the contents of its gut. Scientists found more than 300 pieces of plastic inside the bird. One of the pieces had punctured its gut wall, resulting in its death. The chick was fed the plastic by its parents, who gathered the material from the ocean surface, mistaking it for food. A B

14. 44.4 What Are the Effects of Acid Rain?
Pollutants disrupt ________________ processes of organisms
___________________ from coal-burning power plants, and ________________ from burning gas and oil, are common air pollutants
Pollutant
Substance that is released into the environment by human activities and _______________ with the function of organisms that _______________ in the absence of the substance or with lower levels

15. What Are the Effects of Acid Rain? (cont’d.)
Dry acid ______________: dry dust particles coated with airborne _____________________
_________________ deposition (acid rain): pollutants combine with water and fall as acidic precipitation
Acid rain
_____________ rain that forms when sulfur dioxide and nitrogen oxides mix with water vapor in the atmosphere

16. What Are the Effects of Acid Rain? (cont’d.)
Acid rain in aquatic habitats
____________ fish eggs from ____________
Kills adult fish
Acid rain in forests
Burns tree leaves
Makes trees more ______________ to insects and __________________

17. What Are the Effects of Acid Rain? (cont’d.)
Acid rain __________________ of soils
Positive hydrogen ions ____________ positive nutrient ions such as calcium, causing nutrient loss
Acidity causes soil particles to release metals, such as __________________________

18. ANIMATION: Effect of air pollution in forests
Figure 44.6 {Animated} Acid rain in the United States.
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19. 44.5 What Are the Effects of Ozone Depletion and Pollution?
Ozone is said to be “______________, but _________________”
In the upper atmosphere, the ozone (O3) layer ________________________ ultraviolet (UV) radiation that damages ____________ and causes mutations
Near the ground, it is a __________________

20. What Are the Effects of Ozone Depletion and Pollution? (cont’d.)
___________________, scientists noticed that Earth’s ozone layer (10.5 to 17 miles above sea level) ______________, particularly over Antarctica (the “ozone hole”)
In 1987, countries worldwide agreed to ______________________ of chlorofluorocarbons (CFCs) and other ozone-destroying chemicals – but existing CFCs break down _________________

21. What Are the Effects of Ozone Depletion and Pollution? (cont’d.)
Antarctica
Figure 44.7 Destruction of the ozone layer.

22. What Are the Effects of Ozone Depletion and Pollution? (cont’d.)
Near the ground, __________________ eyes and _____________ tracts of humans and wildlife, and interferes with plant growth
Ground-level ozone forms when nitrogen oxides and _________________ compounds released by burning or evaporating fossil fuels are exposed to sunlight
Warm temperatures ____________________

23. 44.6 What Are the Effects of Global Climate Change?
Climate change is the most ___________ threat to habitats worldwide
___________________/meltwater from glaciers _____________ coastal wetlands
Temperature changes disrupt ___________________ (e.g., tree flowering, animal migration, and breeding seasons)
Some species are moving to higher latitudes or elevations; those that cannot move are ____________________

24. What Are the Effects of Global Climate Change? (cont’d.)
Many _________________ are expected to change as rising land and sea temperatures ____________________, winds, and ________________
Examples
Extremes in rainfall patterns: periods of ______________________ by unusually heavy rains
Increase in ____________________

25. What Are the Effects of Global Climate Change? (cont’d.)
Figure 44.8 Rising temperature. The temperature anomaly is the deviation from average temperature in the period 1951–1980.

26. What Are the Effects of Global Climate Change? (cont’d.)
Muir Glacier in Alaska (1940)
Figure 44.9 Melting glaciers, one sign of a warming world. Water from melting glaciers contributes to rising sea level.
Muir Glacier in Alaska (2004)

27. 44.7 What Is Conservation Biology?
_________________ survey and seek ways to protect the world’s ____________________
Conservation biology
Field of __________________ that surveys biodiversity and seeks ways to maintain and use it
Biodiversity
Of a region, the ___________________ within its species, ____________________, and ________________________

28. What Is Conservation Biology? (cont’d.)
Biological ___________ (biodiversity) is measured at three levels:
______________ diversity within species
______________ diversity
Biodiversity is ____________ at all three levels, in all regions

29. What Is Conservation Biology? (cont’d.)
_____________ ecosystems are ____________ to human survival:
Produce our ___________ and food
___________ , ____________, and ____________ wastes
Prevent erosion and reduce risk of flooding
Allow for new medicines to be _______________ compounds in wild species
Encourage plant breeders to use genes in _____________ to protect and improve crops

30. What Is Conservation Biology? (cont’d.)
People often _____________ environmental protections because they fear ______________________________
Conservation biologists help determine which __________________ be targeted for protection first by ____________ hot spots
____________ region with great biodiversity that is considered a high priority for conservation efforts

31. What Is Conservation Biology? (cont’d.)
Figure The location and conservation status of the land ecoregions deemed most important by the World Wildlife Fund.

32. What Is Conservation Biology? (cont’d.)
Figure Klamath–Siskiyou forest, one of North America’s critical ecoregions. Endangered northern spotted owls (inset) are endemic to this coniferous forest.

33. What Is Conservation Biology? (cont’d.)
Ecological _______________
________________ an area in an effort to restore or create a ______________ ecosystem
Required when a natural ecosystem has been _______________________
Example: Louisiana’s coastal wetlands

34. What Is Conservation Biology? (cont’d.)
Figure Ecological restoration in Louisiana’s Sabine National Wildlife Refuge. Where marshland has become open water, sediments are barged in and marsh grasses are planted on them. The squares are new sediment with marsh grass.

35. 44.8 How Can We Reduce Our Impact?
Ultimately, the health of our planet depends on our ____________________ the principles of ____________________ _____________________
The goal is living _________________
Meeting the needs of the present generation _____________________________ of future generations to meet their own needs

36. How Can We Reduce Our Impact? (cont’d.)
People in industrial nations use ___________________ of resources, and the ___________, ____________, and use of these resources has negative effects on biodiversity
Example: In the U.S., an average new home contains about ___________ of copper wiring and _______________
Strips ____________________; produces waste; causes air and water pollution

37. How Can We Reduce Our Impact? (cont’d.)
Figure Environmental costs of resource extraction.
A Bingham copper mine near Salt Lake City, Utah. This open pit mine is 4 kilometers (2.5 miles) wide and 1,200 meters (0.75 miles) deep, the largest man-made excavation on Earth.
B Pelican covered with oil that accidentally escaped from a deep sea-drilling platform in the Gulf of Mexico. A B

38. How Can We Reduce Our Impact? (cont’d.)
Figure Volunteers restoring the Little Salmon River in Idaho so that salmon can migrate upstream to their breeding grounds.

39. 44.9 A Long Reach
In the Arctic, unusually warm temperatures are affecting the __________________ of sea ice melting and ______________
Polar bears can only reach their main prey by _______________________
Other threats – high amounts of _____________ and organic pesticides are carried to ______________ by winds and ocean currents
Have been found in tissues of polar bears

40. A Long Reach (cont’d.)
Eight countries, including the U.S., control __________________ and have rights to ______________, _______, and _________________
Melting ice sheets make it easier to _________________ and _______________ from the Arctic
_______________ these resources will further harm Arctic species that are already threatened by global climate change

41. A Long Reach (cont’d.)
Figure Polar bears investigate an American submarine that surfaced in ice-covered Arctic waters.