Conservation APBio

Chapter 30Chapter 30

ConservationConservation

Chapter 30 2

What Is Biodiversity?What Is Biodiversity?Biodiversity Biodiversity refers to the variety of living refers to the variety of living

organisms on the planet, including their organisms on the planet, including their genes, ecosystems, and community genes, ecosystems, and community interactionsinteractions

The goal of The goal of conservation biology conservation biology is to preserve is to preserve biodiversity bybiodiversity by• Preventing extinction of species caused by Preventing extinction of species caused by

human activityhuman activity• Maintaining large population numbers that Maintaining large population numbers that

sustain genetic diversitysustain genetic diversity• Preserving community interactions that sustain Preserving community interactions that sustain

ecosystemsecosystems

Chapter 30 3

Ecosystem ServicesEcosystem Services

Why preserve ecosystems?Why preserve ecosystems?• Worth preserving for own sakeWorth preserving for own sake• They support us by providing They support us by providing ecosystem ecosystem

servicesservices

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Chapter 30 5

Ecosystem ServicesEcosystem ServicesEcosystem servicesEcosystem services include processes through include processes through

which natural ecosystems sustain human lifewhich natural ecosystems sustain human life• Purify water and airPurify water and air• Replenish oxygenReplenish oxygen• Pollinate plants and disperse seedsPollinate plants and disperse seeds

Provide wildlife habitatProvide wildlife habitatDecompose wastesDecompose wastesControl erosion and floodingControl erosion and floodingControl pestsControl pestsProvide recreationProvide recreation

Chapter 30 6 Direct BenefitsDirect Benefits

Hunting and fishing for Hunting and fishing for foodfood

Harvesting wood for Harvesting wood for heat and cookingheat and cooking

Extracting medicines Extracting medicines from plantsfrom plants• Example: Tamiflu is Example: Tamiflu is

based on chemicals based on chemicals extracted from the extracted from the Chinese star aniseChinese star anise

Chapter 30 7 Indirect BenefitsIndirect Benefits

Indirect ecosystem services have even Indirect ecosystem services have even greater impact on human welfare and greater impact on human welfare and includeinclude• Soil formationSoil formation• Erosion and soil controlErosion and soil control• Climate regulationClimate regulation• Genetic resourcesGenetic resources• RecreationRecreation

Chapter 30 8

Indirect BenefitsIndirect Benefits

Soil formationSoil formation• Rich soils that sustain agriculture can take Rich soils that sustain agriculture can take

thousands of years to build upthousands of years to build up• Soil harbors nitrogen-fixing bacteria and Soil harbors nitrogen-fixing bacteria and

decomposers that break down wastes and decomposers that break down wastes and recycle nutrientsrecycle nutrients

Chapter 30 9

Indirect BenefitsIndirect Benefits

Plants prevent erosion and provide flood Plants prevent erosion and provide flood control bycontrol by• Blocking wind that blows away loose soilBlocking wind that blows away loose soil• Providing roots that stabilize soil and enhance Providing roots that stabilize soil and enhance

its capacity to hold waterits capacity to hold water

The consequences of destroying riverside The consequences of destroying riverside forest and coastal marshes have been seen forest and coastal marshes have been seen in recent floods in the U.S.in recent floods in the U.S.

Chapter 30 10

1993 – Missouri River

Chapter 30 11

2005 Hurricane Katrina – New Orleans


Plants regulate climatePlants regulate climate• Provide shade, reducing temperatureProvide shade, reducing temperature• Provide windbreaksProvide windbreaks• Buffer against global warming by absorbing COBuffer against global warming by absorbing CO2 2

• Return water to the atmosphere through Return water to the atmosphere through transpiration, influencing water cyclestranspiration, influencing water cycles

Plants harbor genetic resources Plants harbor genetic resources • Genes identified in wild plants may be Genes identified in wild plants may be

transferred into crops to enhance productivity transferred into crops to enhance productivity and disease resistanceand disease resistance


RecreationRecreation• 350 million people visit U.S. national parks and 350 million people visit U.S. national parks and

protected refuges annuallyprotected refuges annually• ““Ecotourism” is an expanding industryEcotourism” is an expanding industry

Chapter 30 14

Ecological EconomicsEcological Economics

Ecological economics Ecological economics evaluates the trade-evaluates the trade-offs that occur when natural ecosystems offs that occur when natural ecosystems are damaged during human profit-making are damaged during human profit-making activitiesactivities

One application is to weigh the pros and One application is to weigh the pros and cons of draining a wetland to irrigate cropscons of draining a wetland to irrigate crops

Possible loss of benefits?Possible loss of benefits?

Chapter 30 15 Ecological EconomicsEcological Economics

Also used to estimate costs of disasters that Also used to estimate costs of disasters that could have been prevented or reduced by could have been prevented or reduced by maintaining natural ecosystemsmaintaining natural ecosystems• $12 billion in damage from the 1993 Missouri $12 billion in damage from the 1993 Missouri

River flood River flood • $100 billion in damages associated with $100 billion in damages associated with

Hurricane Katrina in 2005 Hurricane Katrina in 2005

Chapter 30 16

Ecological EconomicsEcological Economics

Used in government planningUsed in government planningNew York City gets much of its water from New York City gets much of its water from

the Catskills Mountainsthe Catskills MountainsEconomic analysis revealed that protecting Economic analysis revealed that protecting

the mountain ecosystem, which purifies the the mountain ecosystem, which purifies the water naturally, costs less than building a water naturally, costs less than building a water purification plantwater purification plant

Chapter 30 17 ExtinctionExtinction

Extinction is a process that occurs slowly at Extinction is a process that occurs slowly at a a background extinction ratebackground extinction rate under natural under natural conditions conditions

The fossil record suggests that five previous The fossil record suggests that five previous mass extinctionsmass extinctions led to the eradication of led to the eradication of many life forms within short time periodsmany life forms within short time periods

Possible causes of mass extinctions includePossible causes of mass extinctions include• Meteor impactsMeteor impacts• Rapid climate changesRapid climate changes

Chapter 30 18

ExtinctionExtinction

Most biologists believe that human activities Most biologists believe that human activities are now causing a sixth mass extinctionare now causing a sixth mass extinction

The current extinction rate is 100 to 1000 The current extinction rate is 100 to 1000 times the background rate predicted in the times the background rate predicted in the absence of peopleabsence of people

Chapter 30 19 ExtinctionExtinction

Many species may have become extinct Many species may have become extinct before being discovered, as suggested by before being discovered, as suggested by two newly described speciestwo newly described species• The Australian snubnose dolphin and the The Australian snubnose dolphin and the

Aftrican kipunji monkey Aftrican kipunji monkey • Only about 1000 of each remainOnly about 1000 of each remain• Both are threatened by human activity and Both are threatened by human activity and

might have become extinct before discoverymight have become extinct before discovery

Chapter 30 20

Chapter 30 21 Threatened SpeciesThreatened Species

Increasing numbers of species are Increasing numbers of species are threatenedthreatened with with extinctionextinction

Depending on the likelihood of extinction in the Depending on the likelihood of extinction in the near future, threatened species are described as near future, threatened species are described as critically endangeredcritically endangered, , endangeredendangered,, or or vulnerablevulnerable

As of 2004 there are 15,589 threatened species As of 2004 there are 15,589 threatened species • 12% of all birds12% of all birds• 23% of all mammals23% of all mammals• 32% of all amphibians32% of all amphibians• 42% of all turtles and tortoises42% of all turtles and tortoises

Chapter 30 22

Mammals

Chapter 30 23 Threats to BiodiversityThreats to Biodiversity

Two processes are fueling the decline in Two processes are fueling the decline in Earth’s biodiversityEarth’s biodiversity• Increasing use of resources to support human Increasing use of resources to support human

lifestyleslifestyles• Human activities that destroy habitats and pollute Human activities that destroy habitats and pollute

the environmentthe environment

Comparison of humanity’s footprint with Comparison of humanity’s footprint with Earth’s biocapacity in 2002Earth’s biocapacity in 2002• Footprint: 5.4 acres (24 in U.S.)Footprint: 5.4 acres (24 in U.S.)• Biocapacity: 4.5Biocapacity: 4.5

Chapter 30 24 Earth’s “Ecological Capital”Earth’s “Ecological Capital”

Human depletion of the Earth’s ecological Human depletion of the Earth’s ecological capital can be illustrated by estimatingcapital can be illustrated by estimating• Ecological footprint: Ecological footprint: surface area required to surface area required to

produce our resources and absorb our wastesproduce our resources and absorb our wastes• Biocapacity: Biocapacity: actual and available sustainable actual and available sustainable

resources and waste-absorbing capacity of resources and waste-absorbing capacity of EarthEarth

Chapter 30 25 Earth’s “Ecological Capital”Earth’s “Ecological Capital”

Humans have exceeded the Earth’s Humans have exceeded the Earth’s biocapacity by 20%biocapacity by 20%

““Ecological deficit” degrades ecosystems, Ecological deficit” degrades ecosystems, drawing on “ecological capital”drawing on “ecological capital”

Deficit will grow as living standards of less-Deficit will grow as living standards of less-developed nations increasedeveloped nations increase

Chapter 30 26

Chapter 30 27 Human Threats to BiodiversityHuman Threats to Biodiversity

Humans threaten biodiversity in a number of Humans threaten biodiversity in a number of waysways• Habitat destructionHabitat destruction• OverexploitationOverexploitation• Harmful interaction with invasive speciesHarmful interaction with invasive species• PollutionPollution• Global warmingGlobal warming

Chapter 30 28 Habitat DestructionHabitat Destruction

Farming activities over past 11,000 years Farming activities over past 11,000 years have led to loss of ½ of total forest coverhave led to loss of ½ of total forest cover

½ of tropical rain forests cut down over past ½ of tropical rain forests cut down over past 50 years for50 years for• WoodWood• Conversion to agricultureConversion to agriculture

Chapter 30 29


Other activities that lead to habitat destructionOther activities that lead to habitat destruction• Damming riversDamming rivers• Draining wetlandsDraining wetlands• Building roads and housingBuilding roads and housing• IndustryIndustry

Some species need thousands of acres to find Some species need thousands of acres to find food and breedfood and breed

Habitat fragmentation Habitat fragmentation threatens wildlife by threatens wildlife by splitting up natural ecosystemssplitting up natural ecosystems

Chapter 30 31


Preserves created to protect endangered Preserves created to protect endangered species must support a species must support a minimum viable minimum viable population (MVP)population (MVP)• Smallest natural population that can persist in Smallest natural population that can persist in

spite of natural events (disease, fires, floods)spite of natural events (disease, fires, floods)

Chapter 30 33 OverexploitationOverexploitation

Overexploitation Overexploitation involves hunting or harvesting involves hunting or harvesting natural populations at rates that exceed natural populations at rates that exceed replenishmentreplenishment

Impacts 30% of threatened birds and Impacts 30% of threatened birds and mammalsmammals

Over fishing and overharvesting threatens Over fishing and overharvesting threatens many marine life formsmany marine life forms• Cod, sharks, red snapper, swordfish, tuna, Cod, sharks, red snapper, swordfish, tuna,

turtlesturtlesUnintentional trapping in fishing nets Unintentional trapping in fishing nets

threatensthreatens• Whales, porpoises, dolphinsWhales, porpoises, dolphins

Chapter 30 34

Chapter 30 35 Invasive SpeciesInvasive Species

When non-native species are introduced into an When non-native species are introduced into an area, they can becomes area, they can becomes invasiveinvasive

Invasive Invasive species can displace native species species can displace native species and disrupt community interactions throughand disrupt community interactions through• Competion for food and/or habitatCompetion for food and/or habitat• Direct predationDirect predation

Island and lake communities are particularly Island and lake communities are particularly vulnerable to invasive speciesvulnerable to invasive species• The mongoose, imported to Hawaii to control rats, The mongoose, imported to Hawaii to control rats,

now threatens birdsnow threatens birds• The Nile perch, introduced to Lake Victoria for The Nile perch, introduced to Lake Victoria for

fishing, now threatens 200 other speciesfishing, now threatens 200 other species

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Chapter 30 37

Chapter 30 38

PollutionPollution

Pollutants that threaten biodiversity include Pollutants that threaten biodiversity include synthetic chemicalssynthetic chemicals• Plasticizers, flame retardants, pesticidesPlasticizers, flame retardants, pesticides

Enter air, water, soilEnter air, water, soilAccumulate in animal tissues, disrupting Accumulate in animal tissues, disrupting

development or reproductiondevelopment or reproduction

Chapter 30 39 PollutionPollution

Accumulation of high levels of some natural Accumulation of high levels of some natural substances are also threatssubstances are also threats• Mercury, lead, and arsenic from mining and Mercury, lead, and arsenic from mining and

manufacturing are toxic manufacturing are toxic • Oxidized nitrogen and sulfur released by Oxidized nitrogen and sulfur released by

burning fossil fuels lead to acid rainburning fossil fuels lead to acid rain

Chapter 30 40 Global WarmingGlobal Warming

Burning of fossil fuels and deforestation has led Burning of fossil fuels and deforestation has led to increased atmospheric COto increased atmospheric CO22 levels levels

Increase is associated with rising global Increase is associated with rising global temperaturestemperatures

Global warming is associated with dramatic Global warming is associated with dramatic changeschanges• Many species are shifting ranges toward polesMany species are shifting ranges toward poles• Plants and animals initiate springtime activities Plants and animals initiate springtime activities

earlier each yearearlier each year• Glaciers, ice shelves, and ice caps are meltingGlaciers, ice shelves, and ice caps are melting• Extreme weather patternsExtreme weather patterns

Chapter 30 41 Global WarmingGlobal Warming

Leads to habitat destructionLeads to habitat destructionRapid pace of global warming taxes abilities Rapid pace of global warming taxes abilities

of species to adapt to changing conditions of species to adapt to changing conditions through natural selectionthrough natural selection

By 2050: estimated that 1 million species will By 2050: estimated that 1 million species will be threatened with extinction due to global be threatened with extinction due to global warmingwarming

Chapter 30 42

Conservation BiologyConservation Biology

The goals of conservation biology are toThe goals of conservation biology are to• Understand the impact of human activities on Understand the impact of human activities on

species, populations, communities, and species, populations, communities, and ecosystemsecosystems• Preserve and restore natural communitiesPreserve and restore natural communities• Reverse loss of biodiversity caused by Reverse loss of biodiversity caused by

humanshumans• Foster sustainable use of Earth’s resourcesFoster sustainable use of Earth’s resources

Chapter 30 43

Integrated Scientific ApproachIntegrated Scientific Approach

Conservation requires integrated efforts of Conservation requires integrated efforts of many many • Ecologists, geneticists, botanists, zoologistsEcologists, geneticists, botanists, zoologists• Wildlife managersWildlife managers• Environmental lawyersEnvironmental lawyers• Ecological economistsEcological economists• Social scientistsSocial scientists• EducatorsEducators• Individuals making choices and taking actionIndividuals making choices and taking action

Chapter 30 44

Conserving Wild EcosystemsConserving Wild Ecosystems

Each threatened species faces different Each threatened species faces different survival challenges, requiring unique survival challenges, requiring unique conservation effortsconservation efforts

One approach involves the creation of One approach involves the creation of core core reserves and corridorsreserves and corridors

Core reserves Core reserves are protected natural areas are protected natural areas that preserve all levels of biodiversitythat preserve all levels of biodiversity• Exclude all but low-impact human activitiesExclude all but low-impact human activities• Must provide a Must provide a minimal critical areaminimal critical area that can that can

sustain a minimum viable populationsustain a minimum viable population

Chapter 30 45 Conserving Wild EcosystemsConserving Wild Ecosystems

Wildlife corridors Wildlife corridors are are strips of protected strips of protected land that link core land that link core reservesreserves

Allow safe passage Allow safe passage of animals between of animals between habitats separated habitats separated by human by human activities, activities, increasing size of increasing size of reservesreserves

Chapter 30 46

Conserving Wild EcosystemsConserving Wild Ecosystems

Reserves and corridors Reserves and corridors ideally ideally should be should be surrounded by buffer zones that prohibit surrounded by buffer zones that prohibit clear-cutting, mining, freeways and clear-cutting, mining, freeways and housinghousing

However, a San Diego freeway underpass However, a San Diego freeway underpass currently serves as a corridor for cougarscurrently serves as a corridor for cougars

Chapter 30 47

Chapter 30 48

SustainabilitySustainability

Sustainable living and development promote Sustainable living and development promote long-term ecological and human well-beinglong-term ecological and human well-being

Sustainability requiresSustainability requires• Diverse communities and interactionsDiverse communities and interactions• Populations stabilized below the carrying Populations stabilized below the carrying

capacity of the environmentcapacity of the environment• Recycling and efficient use of raw materialsRecycling and efficient use of raw materials• Reliance on renewable sources of energyReliance on renewable sources of energy

Chapter 30 49 SustainabilitySustainability

Sustainable development Sustainable development fulfills present fulfills present needs without compromising the ability of needs without compromising the ability of future generations to meet their needsfuture generations to meet their needs

Current commercial fishing practices (e.g. Current commercial fishing practices (e.g. netting, trawling) endanger many speciesnetting, trawling) endanger many species

Sustainable fishing would requireSustainable fishing would require• Preservation of spawning groundsPreservation of spawning grounds• Limiting fish catchesLimiting fish catches• Developing technologies to avoid damagDeveloping technologies to avoid damag

Chapter 30 50 Biosphere ReservesBiosphere Reserves

One approach to meeting the needs of One approach to meeting the needs of humans in a sustainable manner has been humans in a sustainable manner has been the creation of a world network of the creation of a world network of biosphere biosphere reservesreserves

Part of a program run by the United NationsPart of a program run by the United NationsThe goals are toThe goals are to• Maintain biodiversityMaintain biodiversity• Evaluate techniques for sustaining Evaluate techniques for sustaining

development while preserving local cultural development while preserving local cultural valuesvalues

Chapter 30 51 Biosphere ReservesBiosphere Reserves

Each biosphere consists ofEach biosphere consists of• A central A central core reserve: core reserve: protected area allowing protected area allowing

research and sustainable usesresearch and sustainable uses• A surrounding A surrounding buffer zonebuffer zone: permits low impact : permits low impact

activity and developmentactivity and development• An outer An outer transition areatransition area: supports settlements, : supports settlements,

tourism, fishing, agriculturetourism, fishing, agriculture

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Chapter 30 53

Chapter 30 54 Sustainable AgricultureSustainable Agriculture

Major habitat loss has occurred due to the Major habitat loss has occurred due to the conversion of natural ecosystems to conversion of natural ecosystems to agricultural use agricultural use

Many current agricultural practices are Many current agricultural practices are unsustainable approachesunsustainable approaches• Failure to plant following harvest leads to soil Failure to plant following harvest leads to soil

erosionerosion• Herbicides and insecticides pollute, and kill Herbicides and insecticides pollute, and kill

natural predatorsnatural predators• Irrigation practices deplete underground water Irrigation practices deplete underground water

suppliessupplies

Chapter 30 55

Sustainable AgricultureSustainable Agriculture

Many farmers now realize that sustainable Many farmers now realize that sustainable practices save money and preserve landpractices save money and preserve land• No-till No-till cropping leaves remnants of harvested cropping leaves remnants of harvested

crops as mulchcrops as mulch• Organic farming excludes herbicides, Organic farming excludes herbicides,

pesticides and fertilizerspesticides and fertilizers• Natural predators used to control pestsNatural predators used to control pests• Planting diverse crops reduces pest and Planting diverse crops reduces pest and

disease infestationsdisease infestations

Chapter 30 56

Chapter 30 57 Human Population GrowthHuman Population Growth

Most of the world’s human population lives Most of the world’s human population lives in less-developed countries and lacks basic in less-developed countries and lacks basic amenitiesamenities

75-80 million people are added to the planet 75-80 million people are added to the planet every yearevery year

Growth rate is incompatible with a Growth rate is incompatible with a sustainable increase in quality of life for the sustainable increase in quality of life for the present 6.5 billion inhabitantspresent 6.5 billion inhabitants

Chapter 30 58

Lifestyle and TechnologiesLifestyle and Technologies

Changes that humans can make to develop Changes that humans can make to develop sustainable approachessustainable approaches• Make responsible reproductive choicesMake responsible reproductive choices• Reduce energy consumption and use of fossil Reduce energy consumption and use of fossil

fuelsfuels• Develop and use energy-saving technologiesDevelop and use energy-saving technologies• Rely on renewable energy sourcesRely on renewable energy sources• Make consumer choices that promote Make consumer choices that promote

sustainable practicessustainable practices

Chapter 30Chapter 30

The EndThe End

Technology

Conservation APBio