Upload
aldous-bates
View
236
Download
0
Tags:
Embed Size (px)
Citation preview
Chapter 24Chapter 24
Sustaining Aquatic Sustaining Aquatic BiodiversityBiodiversity
Chapter Objectives:Chapter Objectives:•Define aquatic biodiversity Define aquatic biodiversity •Determine its economic Determine its economic and ecological importanceand ecological importance
•Determine the role of Determine the role of human impacts on human impacts on biodiversitybiodiversity
•Determine ways to protect Determine ways to protect and sustain diversityand sustain diversity
A. Patterns of Marine A. Patterns of Marine BiodiversityBiodiversity
•3 most diverse regions of the 3 most diverse regions of the oceans:oceans:– Reefs, Estuaries, and Ocean Reefs, Estuaries, and Ocean floorfloor
•Diversity is higher near the Diversity is higher near the coastscoasts
•Diversity increases moving Diversity increases moving south to the equatorsouth to the equator
Kelp
Hogfish
Cobia
Pacific sailfishCarrageen
Yellow jack
Batfish
MorayRed snapper
Red algae
Striped drum AngelfishBladder kelp
Sea lettuce Orange roughyChinook salmon
DevilfishGreat barracuda
Laminaria
Porcupine fish
Sockeye salmonGrouper
Dulse Chilean sea bass
Bulrush
Bluegill White bassBrook trout White waterlily
Water lettuce
Rainbow trout
Muskellunge
BowfishWater hyacinth
Rainbow darter
Bladderwort
Black crappieWhite sturgeon
Yellow perch
Largemouth black bass
Walleyed pike
American smelt
Eelgrass Longnose garDuckweedCommon piranha
Carp
African lungfish
Egyptian white lotus
Channel catfish
Velvet cichlid
B. Environmental and B. Environmental and Ecological Importance of Ecological Importance of
Aquatic BiodiversityAquatic Biodiversity•Climate Climate
moderationmoderation•Nutrient Nutrient
recyclingrecycling•Waste dilutionWaste dilution•HabitatHabitat•Reduced storm Reduced storm
impactimpact
•FoodFood
•DrugsDrugs
•RecreationRecreation
•EmploymentEmployment
•Natural Natural resourcesresources
* Only 4% of total federal budget used in aquatic research
Economic Value of Marine Economic Value of Marine ResourcesResources
•$22.5 trillion/yr$22.5 trillion/yr
•Sea Weed is used in Sea Weed is used in pharmaceuticals and pharmaceuticals and cosmetics ($400 million/yr)cosmetics ($400 million/yr)
•Many Species have Many Species have anticancer properties anticancer properties
•Sea Weed and Octopus Sea Weed and Octopus treat Hypertensiontreat Hypertension
•Bone Reconstruction from Bone Reconstruction from coralcoral
•Chemicals from Sponges fight Chemicals from Sponges fight HerpesHerpes
•Barnacles produce binding Barnacles produce binding adhesive for tooth fillingsadhesive for tooth fillings
C. Human Impacts on C. Human Impacts on Aquatic BiodiversityAquatic Biodiversity
1.) Species Loss and 1.) Species Loss and EndangermentEndangerment
•OverfishingOverfishing•Habitat DestructionHabitat Destruction•PollutionPollution
1/3 of all fish species are 1/3 of all fish species are threatened with extinctionthreatened with extinction
2. Marine Habitat Loss and 2. Marine Habitat Loss and DegradationDegradation
•½ of the worlds ½ of the worlds coastal wetlands coastal wetlands have been have been destroyeddestroyed
•½ of the worlds mangroves ½ of the worlds mangroves have disappearedhave disappeared
•70% of beaches have 70% of beaches have serious erosion problemsserious erosion problems
•Dredging destroys bottom Dredging destroys bottom habitatshabitats
3. Freshwater Habitat Loss 3. Freshwater Habitat Loss and and
DegradationDegradation•60% of the 60% of the
worlds rivers worlds rivers are strongly are strongly fragmented fragmented by damsby dams
4. Overfishing4. Overfishing•60% of the worlds 60% of the worlds
commercially valuable fish commercially valuable fish are fished to the limit or are fished to the limit or beyondbeyond
•Overfishing leads to Overfishing leads to Commercial ExtinctionCommercial Extinction–Unravels food chainsUnravels food chains
•Extinction of unintentionally Extinction of unintentionally caught species (Sea Turtles caught species (Sea Turtles and Dolphins)and Dolphins)
Global freshwater
Year
Mea
n t
rop
hic
lev
el
1950 1960 1970 1980 19902.5
2.6
2.7
2.8
2.9
3.0
3.1
3.2
3.3
3.4
3.5
Species at risk<5%
5–9.9%
10–19.9%
20–29.9%
> 30% Fig. 24.6, p. 634
Freshwater Species at Risk
5. Nonnative 5. Nonnative SpeciesSpecies•Species Species
deliberately or deliberately or accidentally accidentally introducedintroduced
ExamplesExamples: : Asian Swamp EelAsian Swamp EelZebra MusselsZebra MusselsAsian CarpAsian CarpSnakeheadSnakehead
6. Pollution6. Pollution•OilOil•AcidAcid•Oxygen demanding wastesOxygen demanding wastes•Toxic Chemicals (Cyanide and Toxic Chemicals (Cyanide and
DDT)DDT)•Coastal developmentCoastal development•SedimentationSedimentation
7. Global Warming7. Global Warming•Alters migration patternsAlters migration patterns•Destroys Coral ReefsDestroys Coral Reefs•Raise water levelsRaise water levels
Pollution of OceansPollution of Oceans
Pollution of FreshwaterPollution of Freshwater
D. Protecting and D. Protecting and Sustaining Marine Sustaining Marine
BiodiversityBiodiversityWhy is it difficult to protect Why is it difficult to protect
marine biodiversity?marine biodiversity?
•Much of the damage is not Much of the damage is not visiblevisible
•Most of the ocean is outside Most of the ocean is outside the jurisdiction of an one the jurisdiction of an one nationnation
•No effective international No effective international agreements agreements
How can we protect and How can we protect and sustain Biodiversity?sustain Biodiversity?
•Protect endangered and Protect endangered and threatened speciesthreatened species
•Establish protected areasEstablish protected areas
•Regulate and prevent Regulate and prevent ocean pollutionocean pollution
•Manage marine fisheriesManage marine fisheries
Problems for the Sea Problems for the Sea Turtles…Turtles…•3 out of 8 major turtle 3 out of 8 major turtle
species are endangeredspecies are endangeredDue to…Due to…•Loss or degradation of Loss or degradation of
habitathabitat•Legal and illegal taking of Legal and illegal taking of
eggseggs•Increased use for food, Increased use for food,
pharmaceuticals and jewelrypharmaceuticals and jewelry•Unintentional captureUnintentional capture
Seal
Bowhead whale
HumpbackwhaleNorthern right
whale
Fin whaleHawksbillturtle
Hawaiianmonk seal
Hawksbillturtle
Greenturtle Leatherback
turtle
Greenturtle
Humpbackwhale Fin whale
Humpbackwhale
Hawksbillturtle
Greenturtle
HawksbillturtleKemp'
sridley turtle
Leatherbackturtle
Olive ridleyturtle
Fin whale
Humpbackwhale
Bowhead whale
Bowhead whale
Northern rightwhale Mediterranean
monk seal
Leatherbackturtle
Hawksbillturtle
Oliveridleyturtle
Leatherbackturtle
Humpbackwhale
Fin whale
Leatherbackturtle
Greenturtle
Oliveridleyturtle
Japanesesea lion
Bowhead whale
Hawksbillturtle
Saimaa seal
Fig. 24.10, p. 637
A Mammal Pushed to A Mammal Pushed to Extinction due to fishing By-Extinction due to fishing By-
CatchCatch
One of the last known baiji, photographed in captivity before its death in 2002. Nobody eats baiji, but it became
a bycatch of other fishing.
Loggerhead119 centimeters
Olive ridley76 centimeters
Leatherback188 centimeters
Hawksbill89 centimeters
Green turtle124 centimeters
Kemp's ridley 76 centimeters
Black turtle99 centimeters
Australian flatback
99 centimeters
Major Species of Sea Turtles
Turtle Exclusion Devices Turtle Exclusion Devices (TED)(TED)•Until recently Until recently
55,000 turtles 55,000 turtles were killed a were killed a year by shrimp year by shrimp trawlingtrawling
•US Government US Government requires requires shrimp shrimp trawlers to use trawlers to use TEDTED
Shrimp trawler
Area enlarged right
Fig. 24.13, p. 640
TED allows shrimp to be captured while letting the Turtles pass through a trap door.
SHARK SHARK FINNINGFINNING
Humans Kill 100 million
sharks a year by finning
Many are killed to make Shark-
Fin Soup
WhalingWhaling
WhalingWhaling::•Easy to Kill:Easy to Kill:
•Large size and the need to Large size and the need to get to the surface to breatheget to the surface to breathe
•Fast ships, harpoon guns, Fast ships, harpoon guns, inflation lances and inflation lances and explosives.explosives.
WhalingWhaling
The Peril of the Blue WhaleThe Peril of the Blue Whale
IWC (International IWC (International Whaling Commission)Whaling Commission)
•Set annual quotasSet annual quotas•Had no power to enforce the Had no power to enforce the
regulationsregulations•USA stopped whaling in USA stopped whaling in
19701970•Japan, Norway, Iceland and Japan, Norway, Iceland and
Russia are attempting to Russia are attempting to overthrow the overthrow the IWCIWC and and CITES TreatyCITES Treaty
National and International National and International Laws to Protect Marine Laws to Protect Marine
Species…Species…**CITES TreatyCITES Treaty::•1975 Convention on International Trade of Endangered Species
•Protects endangered species by a series of permits
•Includes plants or animals, Dead or alive.
Examples of Other Laws and Examples of Other Laws and TreatiesTreaties
•1979 Global Treaty on Migratory Species
•1972 US Marine Mammal Protection Act
•1973 US Endangered Species Act
•1976 US Whale Conservation and Protection Act
•1995 International Convention on Biological Diversity
B. Establish protected areasB. Establish protected areas
Antarctica: 1991 Ban on…Antarctica: 1991 Ban on…
• Mineral and oil explorationMineral and oil exploration
• Wildlife protection, marine Wildlife protection, marine pollution and pollution and environmental monitoringenvironmental monitoring
• Oceans around Antarctica Oceans around Antarctica are not coveredare not covered
Other Areas of Other Areas of Concern…Concern…•United Nations wants to United Nations wants to establish the following establish the following regionsregions
•Black SeaBlack Sea•Persian GulfPersian Gulf•Red SeaRed Sea•South PacificSouth Pacific
Integrated Coastal Integrated Coastal ManagementManagement
Community-based attempt to use Community-based attempt to use resources in sustainable mannerresources in sustainable manner
Fishers, Scientists, business, Fishers, Scientists, business, politicianspoliticians
1)1) Identify shared problems and Identify shared problems and and establish goalsand establish goals
2)2) Agree to workable and cost-Agree to workable and cost-effective solutions that preserve effective solutions that preserve biodiversity.biodiversity.
ChesapeakChesapeake Baye Bay
Reclaiming an Industrial Site Reclaiming an Industrial Site on Lake Michigan on Lake Michigan (SHOW VIDEO – Video Downloads (SHOW VIDEO – Video Downloads
folder)folder)
Beach ErosionBeach Erosion•70% of the worlds beaches are 70% of the worlds beaches are
eroding due to natural and eroding due to natural and human causeshuman causes
•Main problem is rising sea Main problem is rising sea levels due to climate increaseslevels due to climate increases
•Since 1965 the U.S. has spent Since 1965 the U.S. has spent over $4 billion on replenishing over $4 billion on replenishing beachesbeaches
TsunamiTsunami
Engineered Methods to Engineered Methods to Reduce Beach ErosionReduce Beach Erosion
Only temporary solutionsOnly temporary solutions
Many ecologists oppose Many ecologists oppose these methodsthese methods
It is felt that some of these It is felt that some of these methods increase the methods increase the problemproblem
CurrentGroinGroin
-Structures that extend into water, help to trap sand from the current.
-Accumulate sand on upper side, but it is decreased on lower side
SeawallSeawall-Barrier in front of property
-Increase wave energy/erosion to the sides and front of wall
Importing Importing SandSand
-Sand brought in from offshore dredging
-Very disruptive to aquatic biodiversity and very expensive
Drainage Drainage systemsystem
Dischargepipe
Standpipe
Pump
Drain pipe
-Water soaks through sand into pipes that allow it to be pumped back in the ocean.
-Expensive and still in testing stages
Beachsaver Beachsaver modulemodule
Watercurtain
Beachsaver module
Sand carriedback to shore
-Placed offshore to channel water upward and to block sand loss
-Expensive and still being tested
Insuring the CoastsInsuring the Coasts• Proponents feel its necessary Proponents feel its necessary
to stimulate the economyto stimulate the economy• Some feel that gov’t susidized Some feel that gov’t susidized
coastal flood insurance should coastal flood insurance should be eliminatedbe eliminated
1.1. Individuals should pay if they Individuals should pay if they choose to live in the high risk choose to live in the high risk zoneszones
2.2.Ban wetland destructionsBan wetland destructions
Moving The Lighthouse
Regulating and preventing Regulating and preventing Ocean pollution Ocean pollution
-Industrial waste dumping -Industrial waste dumping off U.S. coasts has stoppedoff U.S. coasts has stopped
-London Dumping -London Dumping Convention of 1972Convention of 1972
-1983 permanent ban on -1983 permanent ban on dumping radioactive dumping radioactive wastes at sea wastes at sea
Radioactive waste being dumped into the open ocean
Sustainable Sustainable management of management of marine fisheriesmarine fisheries
-Reduce Overfishing-Reduce Overfishing
-Better -Better measurement of fish measurement of fish populations populations
-Controlling fishing -Controlling fishing methods and access methods and access to fisheriesto fisheries
Means of Projecting Fishery Means of Projecting Fishery PopulationsPopulations
1.1.Maximum sustained yield (MSY)Maximum sustained yield (MSY)
-maximum number of fish that -maximum number of fish that can be harvested annually from can be harvested annually from a fish stock.a fish stock.
2.2.Optimum sustained yield (OSY)Optimum sustained yield (OSY)
-Modification of the MSY -Modification of the MSY -Accounts for interactions with -Accounts for interactions with
other species other species -Provides room for error in -Provides room for error in
estimatesestimates
Individual Transfer Individual Transfer QuotasQuotas
•Permit to catch a certain Permit to catch a certain # of fish# of fish
•Permits can be sold and Permits can be sold and tradedtraded
•Discuss Pros and ConsDiscuss Pros and Cons
Protecting, Sustaining Protecting, Sustaining and Restoring Wetlandsand Restoring Wetlands
•In USA a federal permit is In USA a federal permit is required to fill any wetland required to fill any wetland larger than 3 acreslarger than 3 acres
•Has cut losses by 75% since Has cut losses by 75% since 19691969
Current U.S. Wetland Current U.S. Wetland Policy:Policy:
Zero Net LossZero Net Loss
•Mitigation BankingMitigation Banking::
•Allows destruction of a Allows destruction of a wetland as long as an wetland as long as an equal equal areaarea of the of the same typesame type is is created or restoredcreated or restored
Problems With Created Problems With Created Wetlands…Wetlands…
•Most new wetlands Most new wetlands fail to replace the fail to replace the lost oneslost ones
•Most created don’t Most created don’t resemble the real resemble the real onesones
•ExpensiveExpensive
Plans to Protect and Plans to Protect and Restore WetlandsRestore Wetlands
•Land use planning (steer Land use planning (steer developers away from developers away from wetlands)wetlands)
•Have the created Have the created wetlands inspected wetlands inspected before the original is before the original is destroyeddestroyed
•Prevent the invasion of Prevent the invasion of non-native speciesnon-native species
( )
( )
GULF OFMEXICO Naples
Fort Myers
FLORIDA
Florida Bay
EvergladesNational
Park
Key Largo
ATLANTIC OCEAN
Miami
FortLauderdale
WestPalmBeach
LakeOkeechobee
Unchannelized
Channelized
FLORIDA
Area ofdetail
Agricultural area
Treatment marshWater conservation areaCanal
miles
kilometers
0
0
20
20
40
40 60
60
KissimmeeRiver
Fig. 24.16, p. 651
Can We Save The Everglades ?Can We Save The Everglades ?
Once 60 miles wide, knee deep from lake Okeechobee to Florida Bay
Problems with the Problems with the EvergladesEverglades•US Army Corp of Engineers US Army Corp of Engineers
transformed 103mi Kissimmee transformed 103mi Kissimmee river into a 50 mi canalriver into a 50 mi canal
•Drained the wetlands in the Drained the wetlands in the northnorth
•In the south vast farmland was In the south vast farmland was planted and runoff has changed planted and runoff has changed the plant life of the areathe plant life of the area
•The Everglades are ½ their The Everglades are ½ their original sizeoriginal size
•Not as much freshwater flows Not as much freshwater flows into the Bay (getting salty) into the Bay (getting salty)
Everglades National ParkEverglades National Park•Established in 1947 (20% of Established in 1947 (20% of
the Everglades)the Everglades)
•It is the Most Endangered It is the Most Endangered National ParkNational Park
The Worlds Largest The Worlds Largest Ecological Restoration Ecological Restoration
ProjectProject•US Corp of Army Engineers (2000-2038)US Corp of Army Engineers (2000-2038)•Replumb south Florida ($7.8 billion shared Replumb south Florida ($7.8 billion shared
between USA and State)between USA and State)Goals:Goals:•Restore the curving flow of the Kissimmee Restore the curving flow of the Kissimmee
RiverRiver•Remove 250 mi of canalsRemove 250 mi of canals•Buy and Flood farmlandBuy and Flood farmland•Tap into aquifersTap into aquifers
Protecting, Restoring Protecting, Restoring and Sustaining Lakes and Sustaining Lakes
and Riversand RiversGreatest Threats to Lakes:Greatest Threats to Lakes:
• Pollution, Invasive Species Pollution, Invasive Species and Low water levelsand Low water levels
Greatest Threats to Rivers:Greatest Threats to Rivers:
•Pollution, Disruption of Flow Pollution, Disruption of Flow and Overfishingand Overfishing
National Wild and Scenic National Wild and Scenic Rivers Act - 1968Rivers Act - 1968
•Kept free of developmentKept free of development•Can’t be …Can’t be …•Widened, straightened, dredged, Widened, straightened, dredged,
filled, dammedfilled, dammed
•Only uses…Only uses…•Camping, swimming, sport Camping, swimming, sport
fishing, non-motorized boatsfishing, non-motorized boats
Protecting the Oceans Protecting the Oceans ResourcesResources
3.3.Multispecies managementMultispecies management
– – Studies relationships Studies relationships between species and how between species and how they interact within a food they interact within a food web.web.
4.4.Large marine systemsLarge marine systems
– – Areas of the oceans are Areas of the oceans are controlled and regulated by controlled and regulated by multinational organizations.multinational organizations.
5.5.Precautionary principlePrecautionary principle
– – Better safe than sorryBetter safe than sorry