Biodiversity Under Threat
- Created by: louisemeller
- Created on: 10-11-15 21:20
Biomes and Biospheres.
Biosphere: Part of the world's surface inhabited by living things.
Biome: A large ecosystem with a similar climate, plants, and animals.
9 main biomes:
- Tundra (very cold)
- Taiga (cold)
- Temperate forest (mild)
- Temperate grassland (mild)
- Mediterranian (warm)
- Desert (hot)
- Savannah (hot)
- Tropical rainforest (very hot)
- Equatorial rainforest.
Threats to the biosphere
Threats to the biosphere:
- Over-exploitation
- Invasive species
- Over-hunting
- Pollution
- Climate change
- Habitat change or loss
- Tourism and recreation
- Deforestation
- Conversion to farmland
- Overfishing/harvesting
- Mining and energy
- Eutrophication.
- Coral bleaching
- Introduction of alien species.
Threats to the biosphere
Net Primary Productivity: the rate at which all plants and animals in an ecosystem produce net useful chemical energy.
Biomass: the total amount of organic matter in a given area.
Eutrophication: the pollution of ecosystems with excessive nitrate and phosphate from human activity.
Endemism: being unique in ecological terms and found nowhere else.
Pivotal areas: an area of high biodiversity that is at risk.
Biodiversity hotspot: a specific location that has an enormous specird diversity but is also under threat from human activites.
Two key criteria must be met for an area to be considered a biodiversity hotspot:
- Must contain 1500 species of endemic plants and
- Has to have lost 70% of vegetation.
At least 25 areas around the world meet the criteria. They contain 60% of the world's plant, bird, mammal, reptile, and amphibian species.
Biodiversity hotspots
Examples of biodiversity hotspots:
- California
- Caribbean Islands
- Atlantic Forest
- Guinea Rainforest (congo)
- Cape Floral Region
- Madagascar\
- The Caucasus
- Mountains of S/W China
- Japan
- The Philippines
- Daintree Rainforest
- Great Barrier Reef
- S/W Australia
- New Zealand
Daintree Rainforest- Case Study
Location: Northern Queensland, North East Australia
Why is the Daintree so special?
- Area of international conservation importance, and a World Heritage Site.
- It is one of the most significant ecosystems in the world.
- Contains 65% of bat and butterfly species, 30% of frog, marsupial, and reptile species, and 20% of bird species in Australia.
- Possesses one of the greatest concentrations of primitive flowering plants in the world.
- Cassowaries are endangered and continue to lose habitat and be killed by vehicles and dogs. Only 1000-1500 left.
Tourism
- The most dangerous threat the Daintree faces.
- A big business in the area.
- Tourism and recreation in the region worth A$141.7 million a year in 2002.
- 3500 jobs
Daintree Rainforest- Case Study
People go to Daintree because:
- Scenery and wildlife
- Cape Tribulation
- World Heritage Site
- Isolation
- Four wheel drive experience
- On the way to Cooktown
Activities:
- Bush walking
- 4WD tours
- River cruises
- Horse riding
- Reef diving
- Fishing
Daintree Rainforest- Case Study
How many tourists?
- 1983= 17,000
- 2004= 500,000
Tourism Infranstructure
- 70% = independent tourists
- 30% = organised tours
- 99% cross river by ferry
- Popular with backpackers.
- Thought to be too much accommodation and not enough paths
Port Douglas
- Close to the Daintree
- Affected by increasing tourist numbers
- Type of accommodation has changed and grown rapidly
Daintree Rainforest- Case Study
How many tourists?
- 1983= 17,000
- 2004= 500,000
Tourism Infranstructure
- 70% = independent tourists
- 30% = organised tours
- 99% cross river by ferry
- Popular with backpackers.
- Thought to be too much accommodation and not enough paths
Port Douglas
- Close to the Daintree
- Affected by increasing tourist numbers
- Type of accommodation has changed and grown rapidly
Daintree Rainforest- Case Study
Changes caused by visitors:
- Large supermarket built in 1999- local shops affected.
- Property boom = rising house prices
- Increasing proposals for resort complexes- 5 in 2008.
- Possibility of spreading into Daintree.
Deforestation in Daintree
- Sparesly populated- 350 dwellings.
- 550 residents in 2000.
- Small areas of forest divided into 1000 plots for sale
- Some occupied and owners respect the environment.
- Others bulldozed and turned into cattle ranches.
- Once species of red cedar became extinct in 2000.
- 85 rare plant species at risk on plots.
Daintree Rainforest- Case Study
Main limits to development:
- Ferry crossing Daintree River limits traffic levels.
- No mains electricity north of the river- own generator and solar panels needed.
- Local services only support a small population- no mains water, no sewage disposal, and few shops and services.
Managing the Daintree
- The Daintree is under threat from human activity.
- There are a range of strategies and players involved in managing biodiversity.
- They can come into conflict.
- The Wet Tropics Management Authority
- Douglas Shire Council
- Rainforest Co-operative Research Council
- Australian Rainforest Foundation
- Wildlife Preservation Society of Queensland
- Australian Tropical Research Foundation
Daintree Rainforest- Case Study
The Wet Tropics Management Authority:
- Responsibe for managing the Wet Tropics as a World Heritage Site.
- Main functions include:
- Developing and implementing plans and policies
- Researching and maintaining the state of the area
- Developing management agreements with landholders and aboriginees
- Educating tourists
- Funding and promoting the area.
Douglas Shire Council:
- Local council for the Daintree until 2008.
- In 2003, they increased the price of ferry crossings by $4 to finance land buy-back. Tour operations objected, saying tourists wouldnt pay.
- It rejected proposals to build a bridge over the river and to introduce an extra ferry.
- Locals fear that the developement that occured in Cairns will happen in the Daintree.
Daintree Rainforest- Case Study
Rainforest Cooperative Research Council:
- Produced a report on the future of the Daintree in 2000. It found that unless action was taken, residential development would increase, biodiversity would be lost, and attractiveness to tourists would decline.
- Strategies included:
- Community development-residents to be involved in stewardship and conservation.
- Biodiversity conservation- identify biodiversity hotspots where no development should occur.
- Douglas Shire Council- introduce planning controls for biodiversity conservation.
- Electricity supply- those north of Cooper Creek must use remote area power supplies.
- Indigenous people- recognise the rights of aboriginal peoples to own land and promote their culture within the forest.
- Water supply and waste management- use the best available domestic technology for waste disposal.
- Roads and ferry- ferry to remain gateway to the area.
- Tourism- increase numbers to 550,000 a year ti support the economy.
Daintree Rainforest- Case Study
Australian Rainforest Foundation
- Non-profit organisation that is dedicated to education, research, and habitat rehabilitation.
- The ARF plans to create a 250km wildlife corridor to protect the cassowary.
- Wildlife corridors conserve biodiversity by enabling species to move, disperse, feed, and breed.
- Funding has been used to buy-back land in order to reduce the area for development.
Wildlife Preservation Society of Queensland
- Community based, non-profit conservation group.
- Committed to an ecologically sustainable future for people and wildlife.
- Supported a ban on development in the Daintree in 2004.
Australian Tropical Research Foundation
- Created in 1993 and oversees the operation of the Cape Tribulation Tropical Research Station and the Wet Tropics Visitor Centres.
- These facilities encourage research and conservation by increasing understanding of the ecosystem.
Daintree Rainforest- Case Study
Deforestation
- Around 25% of the original Daintree canopy has been removed.
- Much of the biodiversity has beed destroyed.
Removals occur for the following reasons:
- Logging
- Road building
- Agriculture
- Residential
- Tourist areas
- Mining sites
- Removal of tree canopy exposes the rainforest floor and increases runoff.
Mangroves
What Mangroves Do:
- Support a range of marine and terrestrial biodiversity.
- They stabilise coastlines from erosion.
- They provide a nursery for coastal fish.
Eco-regions: Are large areas of land or water with geologival distinction.
Sunda Mangroves
- The most diverse mangroves
- Sunda mangroves are found around Borneo and Sumatra; this region has been designated a wetland hotspot
Mangroves
Conditions for the growth of mangroves:
- Inter-tidal regions
- Tropical and sub-tropical regions
- Temperature- above 20 degrees
- Shorelines must be protected from waves
- Waterlogged soils
- Inundated or flooded regions
- Intense sunlight and hot weather
- Survive in limited fresh water
Prop roots: modified roots that grow from the lower part of a stem down to the ground.
Pneumatphores: specialised aerial roots that allow plants to breathe in waterlogged soil.
Lenticles: spongy areas in the corky surface of plant parts that allow gas exchange.
Zonation: the distribution of organisms in biogeographic zones.
Chao Mai, Trang Province, Thailand- Case Study
- Coastal village; subsistence fishing is vital.
- In the late 1960s, some fishermen were given loans to buy bigger boats and better equipment.
- The government began to cut mangrove forests for charcoal production- mangroves depleted.
- Depletion of mangroves led to reduction is marine nurseries and depletion of sea grass.
- Larger fishing boats with drag nets have also destroyed sea grass that acted as marine nurseries.
- Severe impact on villagers with small boats who fish in shallow waters.
- Conflicts between villagers depending on mangroves and those destroying them.
Community mangrove forests
- Yadfon is a small organisation in Thailand, formed in 1985. It works with villagers in Chao Mai on environmental issues and securing their future livelihood.
Chao Mai, Trang Province, Thailand- Case Study
- Chao Mai has faced two problems:
- Mangrove destruction- mangroves being destroyed to produce charcoal, which affected seafood supply. Yadfod created an 80 hectare community managed mangrove forest- no shrimp farms within its boundaries. Mangrove forest now managed by the community.
- Destruction of seagrass- caused by large fishing boats and drag nets. It is an important nursery habitat for fish and prawns. To protect the sea grass, a publicity campaign was launched to reduce destruction.
Had Chao Mai Marine National Park
- Since signing the Ramsar Convention, Thailand has designated 10 areas of wetland as Ramsar Sites. They include the Had Chao Mai Marine National Park.
- It has a range of wetland habitats including mangroves, mudflats, sandy beaches, and coral reefs.
Chao Mai, Trang Province, Thailand- Case Study
Had Chao Mai Marine National Park
- It is important in terms of biodiversity:
- At least 212 bird species, including vulnerable and endangered ones.
- Home to at least 22 mammal species, including the dugong.
- A least 75 fish species- critical to local people's livelihoods.
Reliance on Wetlands
- Chao Mai is home to 10,000 people, many of whom make a living from fisheries.
- Local people rely on the wetlands as a source of water, agriculture, and aquaculture.
- 250,000 tourists visit the area each year; local communities earn income from tourist activities.
Threats
- Habitat change (conversion of wetlands to aquaculture)
- Overfishing and destructuve fishing activities.
- A lack of pollution control.
Background- Ramsar Sites
Ramsar sites
- 'Ramsar Convention on Wetlands' is an intergovernmental treaty established in the Iranian city of Ramsar.
- "The conservation and wise use of all wetlands through local, regional, and national actions and international cooperation, *** a contribution towards achieving sustainable development throughout the world".
- The Ramsar Convention recognises that wetlands are important ecosystems for consrvation and human wellbeing.
- Ramsar Convention= 158 states, 1720 wetland sites.
Background- Carbon Sequestration
Carbon Sequstration
- Mangroves sequester (take up) 1.5 metric tonnes/hectare/year of carbon.
- Current rates of mangrove destruction mean that 225,000 metric tonnes of carbon sequstration potential is lost each year.
- The layers of soil and peat below the mangroves have a carbon content of 10% or more. When th mangroves and destroyed, the sediment is dug up and the carbon is released.
- Clearing mangroves and excavating the substrate for shrimp ponds means a release of carbon which is "some 50 times the sequestration rate"
Mangroves
- Human and wildlife benefits of mangroves
- Mangroves play a critical role in protecting lives and property in low lying coatsal areas from storm surges.
- They stabilise shores and improve water quality.
- The annual economic value of mangrove is estimated to be at $80,000-$360,000 per acre.
Threats that mangroves face:
- Current rate of mangrove loss is 1% PA. This is because of:
- Aquaculture, shrimp farming, and fishing.
- Deforestation.
- Cattle rearing, agriculture, building materials.
Mangroves
Managing the threats to mangroves
- Organisations involved:
- TUE Asian Pacific (TUEAP)- independent, non-profit meadia organisation that is dedicated to communicating sustainable development, humanitarian and social justice issues.
- Wetlands International- independent and non-profit. A global organisation that sustains and restores wetlands and resources for people and biodiversity.
- Ramsar Sites- in place since 1971 and provide an information service on internationally important wetlands.
- Wetland Greenbelts- strips of natural or artificially created coastal vegetation designed to prevent coastal erosion and mitigate impacts of natural coastal hazards.
- Wilflife Aid/ WWF- wildlife conservation society. Internation conservation organisations active in wetland regions providing additional funds for conservation projects.
The Great Barrier Reef- Background
Background
- The Barrier Reef is the largest living structure on the planet.
- It stretches over 2900km.
- It provides a home for a huge biodiversity of plants and animals.
- The Reef extends over 14 degrees of latitude, and is one fo the most complex natural ecosystems in the world.
- The Great Barrier Reef Marine Park civers 344,400km2 in area.
- The marine park includes 3000 coral reefs, 600 continental islands, 300 coral cays, and about 150 inshore mangrove islands.
- The marine park extends south from the northern tip of Queensland to just north of Bundabers.
The Great Barrier Reef Marine Park
The Marine Park
- The Marine Park was created in 1975 through the Great Barrier Reef Marine Park Act.
- Coral initially made the Great Barrier Reef famous yet only compromise about 7% of the Marine Park and the world heritage area.
- The area is dividen into different zones. Each zone has different rules outlining permitted and prohibited activities.
The Biodiversity
- 2900 coral reefs and 900 cays and islands/
- 2000km2 of mangroves and 52% of the world's mangrove species.
- 133 types of shark and ray, and more than 30 species of whale and dolphin.
- 1625 types of fish.
- 100 species of jelylfish.
The Great Barrier Reef- impacts of climate change
Impacts of climate change on the Reef:
- Coral bleaching- warmer water temperatures brought on by climate change stress corals because they are very sensitive to changes in temperature.
- If water temperatures are too high for too long, the zooxantheilae they depend on for food leave their tissue, leaving them white.
- Bleached corals are weak and less able to combat disease.
- Ocean acidification- As the carbon dioxide in the ocean increaes, ocean pH becomes more acidic.
- With ocean acidification, corals cannot absorb the calcium carbonate they need to maintain their skeleton- the reefs dissolve.
The Great Barrier Reef- impacts of tropical cyclon
Impacts of tropical cyclones:
- Extreme weather events damage coral reefs and seagrass beds, leading to pressures on important species such as dugong and greent turtle.
- Also have implications for industries and communities that depend on the reef- direct damage to infrastructure and impact to natural resources.
- Cyclonic winds and floodwaters have a severe impact on coral reefs. Floodwaters entering the reef cause stress because of reduced salinity, increased turbidaty, and icnreased amounts of nutrients and chemicals.
- Prolonged exposure can lead to deaths of corals and seagrasses. Corals and seagrasses are essential habitat and food for fish, dugong, and turtles- this can havce flow-on effects.
Invasive species
What is an invasive species?
- Invasive alien species are species whose introduction and/or spread outside their natural ecosystem is threatening other biodiversity.
- Alien species have been estimated to cost economies hundreds of billions of dollars each year.
- A species introduction is usually caused by human transportation and trade.
Grey Squirrels
- Significant factor in the decline of the native red squirrel- greys carry the pox virus.
- Red squirrel= severely threatened and extinct in many parts of the UK.
- Methods of grey squirrel control- tunnel trapping, shooting, poisoning, live cage trapping.
Invasive species
Chinese mitten crabs
- Found on coasts from Japan to the mainland of China, Korea, Peninsula, and along the yellow sea.
- Found in southern Wales and southern Ireland in 2006, and they are spreading around the British Isles.
- Now found in estuaries and rivers bordering the North Sea, Baltic Sea, an Atlantic coasts, to as far as 700km upstream.
- First appeared in North America in the 1980s and spread. Found for the first time on the US Atlantic coast in 2006.
- Ballast water of shipping vessels has been a primary method of alien speices introduction throughout the world.
Case Study- Galapagos Islands
Geography/location:
- A chain of volcanic islands in the Pacific ocean, distributed on either side of the equator.
- They are part of continental Ecuador, and spread over a distance on 220km.
- The island group consists of 18 main islands, 3 smaller islands, and 107 rocks and isles.
- The first islands formed around 90 million years ago.
- The Galapagos Islands form a national park and biological marine reserve.
- They have a total population of 25,000; only 5 islands are inhabited.
History of the Islands
- Discovered accidentally by the Spanish in 1535, and first appeared on maps around 1570.
- Artifacts such as pottery have been found on several islands, suggesting South American natives may have visited the islands, but not permentantly settled.
- Until the early 19th century, the islands were used as a hideout for English pirates who preyed on Spanish ships carrying gold and silver.
Case Study- Galapagos Islands
Biodiversity
- Famous for endemic species that were studied by Charles Darwin.
- Galapagos tortoise
- Galapagos green turtle
- Galapagos penguin- only living tropical penguin.
- Galapagos sea lions
Conservation
- It wasn't until the 1050s that actionw as taken to control the exploitation of native flora and fauna.
- In 1959, the Ecuadorian government declared 97.5% of the Island's land as a national park, excluding settled areas.
- The Charles Darwin Foundation was founded to conduct research and report to the government for effective management of the Galapagos.
- In 1978, UNESCO recognised the Islands as a World Heritage Site.
Case Study- Galapagos Islands
Environmental Threats
- Introduced plants and animals are the main threat, including feral goats, cattle, and cats. They are quick to reproduce and have no predators- the decimated the native species.
- Introduced plants have invaded large areas and elimated endemic species on several islands, like Santa Cruz.
- Pirates introduces many species to the islands, including goats and dogs.
- On the islands there are non-native goats, pigs, dogs, rats, cats, mice, sheep, horses, donkeys, cows, cattle, and poultry.
- Dogs and cats kill the native birds and destroy nests.
- Cattle and donkeys eat all the vegetation and compete with native species for water.
Terminology
Organic Productivity: a measure of how quickly vegetation grows.
Species Diversity: a meaure of the diversity within an ecological community that incorporates both species richness and the evenness of abundance.
Genetic Diversity: the theory that genetic diversity and biodiversity are dependent on each other- diversity within a species is necessary to maintain diversity among species.
Ecosystem Diversity: the concept that biodiversity is essential for the functioning and sustainability of an ecosystem.
Biomass: the total amount of organic matter in a given area.
Biodiversity Hotspots: areas with high concentrations of biodiversity.
Pivotal areas: areas with high concentrations of hotspots.
Endemic: unique to a certain area e.g. the Galapagos Islands.
Alien Species: those which are not native to an area but have been introduced, almost always by human activity.
Terminology
Eutrophication: the process by which fertiliser causes rapid algal and plant growth and the depletion of oxygeb available for aquaic species.
Coral Bleaching: the loss of colour of corals. Under tress, coral will expel the algae which give it its colour.
Buy-Back: a Queensland government initiative in which the ARF is implementing.
Inter-Tidal Areas: the area that is exposed to the air at low tide and submerged at high tide.
Eco-Region: a large area of land or water with geographically distinct natural communities, where the majority of species interact for their long-term survival.
Lenticles: spongy areas in the corky surface of plant parts that allow gas exchange between the atmosphere and the internal tissues of the plant.
Anaerobic: any organism or process which can or must exist without free oxygen from the air.
Prop Roots: modified roots that grow from the lower part of a stem or trunk down to the ground, providing a plant with extra support.
Terminology
Pneumatophores: specialised aerial roots which enable plants to breathe air in habitats which have waterlogged soil.
Zonation: the distribution of organisms in biogeographic zones.
Red Mangroves: found closest to the coast where they asborb wave force, protect inland areas, and can survive permenant waterlogging.
Black Mangroves: live further inland, protected by red mangroves. They will die is permenantly waterlogged.
White/Grey Mangroves: live the furthest inland and are least able to survive waterlogging.
Aquaculture: the production of aquatic organisms under controlled conditions
Sustainable Yield: ways in which ecosystems can be productive and still sustainable.
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