Biodiversity Under Threat

HideShow resource information

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.
1 of 35

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.
2 of 35

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.

3 of 35

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
4 of 35

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
5 of 35

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
6 of 35

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
7 of 35

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
8 of 35

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.
9 of 35

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
10 of 35

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.
11 of 35

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.
12 of 35

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.
13 of 35

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.
14 of 35

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
15 of 35

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.

16 of 35

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.
17 of 35

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.
18 of 35

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.
19 of 35

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.
20 of 35

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"
21 of 35

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.
22 of 35

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.
23 of 35

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.
24 of 35

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.
25 of 35

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.
26 of 35

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.
27 of 35

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.
28 of 35

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.
29 of 35

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.
30 of 35

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.
31 of 35

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.
32 of 35

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.

33 of 35

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.

34 of 35

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.

35 of 35

Comments

No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Ecosystems and biodiversity under threat resources »