Chapter 5: Natural Systems Chapter 5: Natural Systems Under StressUnder Stress

Daniel BurtonDaniel Burton

Geoff KoeglerGeoff Koegler

OverviewOverview

• Chapter SummaryChapter Summary

• Fact CheckFact Check

Natural Systems Under Natural Systems Under StressStress

““Mercilessly expanding human Mercilessly expanding human demands are putting stresses on demands are putting stresses on forests, rangelands, and fisheries forests, rangelands, and fisheries that they cannot withstand. We are that they cannot withstand. We are also destroying many of the plant also destroying many of the plant and animal species with which we and animal species with which we share the planet”.share the planet”.

Shrinking ForestsShrinking Forests

• Effects of DeforestationEffects of Deforestation

• Pressures on DeforestationPressures on Deforestation

• The importance of the world’s forests The importance of the world’s forests

Losing SoilLosing Soil

• Topsoil and soil erosionTopsoil and soil erosion

• Dust Bowl ExamplesDust Bowl Examples

• Global effects of Dust BowlsGlobal effects of Dust Bowls

Grassland to DesertGrassland to Desert

• Grass-based livestock economies Grass-based livestock economies

• Livestock Vs. Carrying CapacityLivestock Vs. Carrying Capacity

• Land DegradationLand Degradation

Advancing DesertsAdvancing Deserts

• DesertificationDesertification

• Stages of DesertificationStages of Desertification

• Effects of DesertificationEffects of Desertification

Collapsing FisheriesCollapsing Fisheries

• Demand increase for seafoodDemand increase for seafood

• Effects of over-fishingEffects of over-fishing

• Canadian CodCanadian Cod

• EU SolutionEU Solution

• Dead ZonesDead Zones

Disappearing Plants and Disappearing Plants and AnimalsAnimals

• The sixth great extinctionThe sixth great extinction

• Habitat DestructionHabitat Destruction

• Bird PopulationBird Population

• Bee PopulationBee Population

• Non-native SpeciesNon-native Species

Fact Check: Natural Systems Fact Check: Natural Systems Under StressUnder Stress

• Loss of ForestsLoss of Forests

• DesertificationDesertification

• Collapsing FisheriesCollapsing Fisheries

• ExtinctionExtinction

Loss of ForestsLoss of Forests

• Brown: Forests make up 4 billion Brown: Forests make up 4 billion hectares today, down from 5 billion hectares today, down from 5 billion in 1900 in 1900

• U.N. FAO:U.N. FAO: World-Wide Forests

3940

3960

3980

4000

4020

4040

4060

4080

4100

1998 1999 2000 2001 2002 2003 2004 2005 2006

Year

Hec

tare

s (m

illi

on

s)

Loss of ForestsLoss of Forests

• Forest cover is growing in developed Forest cover is growing in developed countriescountries

(U.N. FAO)(U.N. FAO)

Loss of ForestsLoss of Forests

• Forest cover is declining in developing Forest cover is declining in developing countriescountries

(U.N. FAO)(U.N. FAO)

Loss of ForestsLoss of Forests

• The AmazonThe Amazon– Brown: Brazil has lost 20% of the Brown: Brazil has lost 20% of the

Amazon since 1970Amazon since 1970– U.N. FAO:U.N. FAO:

% of 1970 Cover Remaining

0

20

40

60

80

100

120

1965 1970 1975 1980 1985 1990 1995 2000 2005

Year

%

DesertificationDesertification

• Brown: Sahara Desert Brown: Sahara Desert is growing rapidlyis growing rapidly– Nigeria: losing 351,000 Nigeria: losing 351,000

hectares of land each hectares of land each yearyear

• Center for Center for International Earth International Earth Science Information:Science Information:– Lack of rain is the Lack of rain is the

largest causelargest cause

DesertificationDesertification

• Brown: China losing 3,600 square km per Brown: China losing 3,600 square km per year, up from 2,100 in the 1970s and 80s, year, up from 2,100 in the 1970s and 80s, – Resulted in the loss of over 24,000 villages Resulted in the loss of over 24,000 villages

during the past 50 yearsduring the past 50 years

• China is indeed losing China is indeed losing this much land (China this much land (China Environmental Science Environmental Science Presses)Presses)– Disputes as to how many Disputes as to how many

villages have been lost (4,000 villages have been lost (4,000 according to the Boston Globe)according to the Boston Globe)

Collapse of FisheriesCollapse of Fisheries

• Brown: World-wide fish catch at a Brown: World-wide fish catch at a historic high of 96 million tons in 2000, historic high of 96 million tons in 2000, 75% of fisheries are over fished75% of fisheries are over fished

• U.N. FAO:U.N. FAO:

• 80% of Fisheries80% of Fisheries

are over fishedare over fished

(Oceana)(Oceana)

Collapse of FisheriesCollapse of Fisheries

• Brown: Canadian Cod Fishery Brown: Canadian Cod Fishery collapsed in 1990 as a result of collapsed in 1990 as a result of overfishingoverfishing

• U.N. FAO:U.N. FAO:

Collapse of FisheriesCollapse of Fisheries

• Brown: Chesapeake Bay oyster Brown: Chesapeake Bay oyster catches have decreased rapidlycatches have decreased rapidly

• Chesapeake Bay Program:Chesapeake Bay Program:

Collapse of FisheriesCollapse of Fisheries

• Brown: Gulf of Mexico “Dead Zone” (size Brown: Gulf of Mexico “Dead Zone” (size of New Jersey) kill fish due to algae bloomsof New Jersey) kill fish due to algae blooms

• Sierra Club: 4,565 square miles, roughly Sierra Club: 4,565 square miles, roughly the size of Connecticutthe size of Connecticut

(NASA)(NASA)

ExtinctionExtinction

• Brown: An alarming amount of species are Brown: An alarming amount of species are vulnerable or in immediate danger of vulnerable or in immediate danger of extinction extinction – 12% of birds 12% of birds – 20% of mammals20% of mammals– 39% of fish39% of fish

• Conservation Conservation International StudyInternational Study– 36% of land mammals36% of land mammals– 61% of ocean mammals61% of ocean mammals

SummarySummary

• Lester Brown clearly depicts how Lester Brown clearly depicts how several of earth’s natural systems are several of earth’s natural systems are under stressunder stress

• Uses accurate and interesting Uses accurate and interesting information to convey issues regarding:information to convey issues regarding:– Loss of ForestsLoss of Forests– DesertificationDesertification– Collapsing FisheriesCollapsing Fisheries– ExtinctionExtinction

““On the plus side, we now have more On the plus side, we now have more information on the state of the earth information on the state of the earth and the life on it than ever before. and the life on it than ever before. While knowledge is not a substitute While knowledge is not a substitute for action, it is a prerequisite for for action, it is a prerequisite for saving the earth’s natural systems- saving the earth’s natural systems- and the civilization that they and the civilization that they support”.support”.

Questions?Questions?

ReferencesReferences

• Chesapeake Bay Program. (2008). Chesapeake Bay Program. (2008). Oysters: Commercial Harvest. Oysters: Commercial Harvest. Retrieved October 25, 2008, from Retrieved October 25, 2008, from http://www.chesapeakebay.net/status_oysterharvest.aspx?menuitem=19819http://www.chesapeakebay.net/status_oysterharvest.aspx?menuitem=19819

• Compton, T, Dregne, H, Newcomb, W. (1991). Compton, T, Dregne, H, Newcomb, W. (1991). Expansion and Contraction of the Sahara Desert from 1980 to 1990.Expansion and Contraction of the Sahara Desert from 1980 to 1990. Center for International Center for International Earth Science Information NetworkEarth Science Information Network Retrieved October 25, 2008, from Retrieved October 25, 2008, from http://www.ciesin.org/docs/005-319/005-319.htmlhttp://www.ciesin.org/docs/005-319/005-319.html

• Datong, Ning. (1989). Datong, Ning. (1989). An Assessment of the Economic Losses Resulting from Various Forms of Environmental Degradation in China.An Assessment of the Economic Losses Resulting from Various Forms of Environmental Degradation in China. China China Environmental Science PressesEnvironmental Science Presses Retrieved October 25, 2008, from http://www.library.utoronto.ca/pcs/state/chinaeco/desert.htmRetrieved October 25, 2008, from http://www.library.utoronto.ca/pcs/state/chinaeco/desert.htm

• Food and Agriculture Organization of the United Nations. (2008). Food and Agriculture Organization of the United Nations. (2008). Fisheries and Aquaculture Department. Fisheries and Aquaculture Department. Retrieved October 25, 2008, from Retrieved October 25, 2008, from http://www.fao.org/fishery/enhttp://www.fao.org/fishery/en

• Food and Agriculture Organization of the United Nations. (2008). Food and Agriculture Organization of the United Nations. (2008). Forestry. Forestry. Retrieved October 25, 2008, from Retrieved October 25, 2008, from http://www.fao.org/forestry/home/en/http://www.fao.org/forestry/home/en/

• NASA. (2007). NASA. (2007). Mississippi Dead Zone. Mississippi Dead Zone. Retrieved October 25, 2008, from http://www.nasa.gov/vision/earth/environment/dead_zone.htmlRetrieved October 25, 2008, from http://www.nasa.gov/vision/earth/environment/dead_zone.html

• Oceana. Oceana. Over 80% of Fisheries Overfished: ReportOver 80% of Fisheries Overfished: Report. Retrieved October 25, 2008, from . Retrieved October 25, 2008, from http://www.oceana.org/fileadmin/oceana/uploads/dirty_fishing/cut_the_bait/AFP_27_may_08.dochttp://www.oceana.org/fileadmin/oceana/uploads/dirty_fishing/cut_the_bait/AFP_27_may_08.doc

• Pocha, J. (September 18, 2006). Pocha, J. (September 18, 2006). China’s Dangerous Dustbowl. China’s Dangerous Dustbowl. Boston Globe. Retrieved October 25, 2008, from Boston Globe. Retrieved October 25, 2008, from http://www.boston.com/yourlife/health/other/articles/2006/09/18/chinas_dangerous_dustbowl/ http://www.boston.com/yourlife/health/other/articles/2006/09/18/chinas_dangerous_dustbowl/

• Roach, J. (October 5, 2004). Roach, J. (October 5, 2004). Bee Decline May Spell End of Some Fruits, Vegetables. National Geographic NewsBee Decline May Spell End of Some Fruits, Vegetables. National Geographic News . Retrieved October 25, 2008, . Retrieved October 25, 2008, from http://news.nationalgeographic.com/news/2004/10/1005_041005_honeybees.htmlfrom http://news.nationalgeographic.com/news/2004/10/1005_041005_honeybees.html

• Sierra Club. (2008). Sierra Club. (2008). The Dead Zone in the Gulf of Mexico. The Dead Zone in the Gulf of Mexico. Retrieved October 25, 2008, from Retrieved October 25, 2008, from http://www.sierraclub.org/cleanwater/waterquality/deadzone.asphttp://www.sierraclub.org/cleanwater/waterquality/deadzone.asp

• Weiss, K. (October 6, 2008). Weiss, K. (October 6, 2008). Many Wild Animals Face Extinction, Survey Finds.Many Wild Animals Face Extinction, Survey Finds. Chicago Tribune. Retrieved October 25, 2008, from Chicago Tribune. Retrieved October 25, 2008, from http://www.chicagotribune.com/news/nationworld/chi-extinct-mammalsoct07,0,1044472.storyhttp://www.chicagotribune.com/news/nationworld/chi-extinct-mammalsoct07,0,1044472.story