Chap. 10 - Sustaining Terrestrial Biodiversity

• Costa Rica now devotes a larger portion of its land to biodiversity conservation than does any other country
• Harvesting trees

  1. Build roads for access and timber removal

  2. Design logging roads

  3. Selective cutting

  4. Clearcutting

  5. Strip cutting
• The clearing of old growth forests can result in severe erosion and loss of topsoil
• China leads the world in new forest cover due to its fast-growing tree plantations
• Drier forests are prone to intense forest fires
• A large area of the nation's remaining old growth & fairly diverse second growth forest has been cut down and replaced with biologically simplified tree plantations
• Forests in the U.S. cover more area today than they did in 1920, primarily due to secondary succession
• Successful efforts to reduce deforestation

  Government pays landowners to maintain or restore tree cover
• Deforestation is the temporary or permanent removal of large expanses of forest for agriculture, settlements, and other uses
• Scientists are concerned about the increased clearing of the boreal forests in Alaska, Canada, Scandinavia, & Russia


  The boreal forest makes up ¼ of the world’s forested area
• Types of forest fires

  • Crown Fires (Top Image)
  • Surface Fires (Bottom Image)
• Many cleared forests in the United States have grown back
• Protected forests make up 40% of the country's total forest area
• Reasons for Costa Rica's high biodiversity

  • Country’s geographical location
  • Government’s strong conservation efforts
• Tropical rainforests currently cover 6% of the world; they used to cover twice that
• We Can Reduce the Demand for Harvested Trees

  1. Up to 60% of wood consumed in the U.S. is wasted unnecessarily: inefficient use of construction materials, excess packaging, overuse of junk mail, failure to reuse substitutes for wooden shipping containers

  2. Kenaf= tree-free fibers yield more paper pulp per area/require less use of pesticides (best option for tree-free paper making)

  3. Kenaf could replace wood-based paper within 20-30 years

  4. Reduce demand for tree cutting= reduce throwaway paper products
• What We Know about Tropical Rainforests

  • Tropical rain forests are being rapidly cut down in Africa, Southeast Asia, and South America
  • This deforestation contributes greatly to climate change since trees are major carbon absorbers
  • Forest burning can lead to carbon elevations and topsoil erosion which prevents crop growth
  • 20%-30% of the Amazonian Basin will turn into savanna in the next 50 years if burning and deforestation continues
  • At least 50% of the world's terrestrial plants, animals, and insects live in forests and are in high danger of extinction due to deforestation
• We Can Manage Forests More Sustainably

  1. Certification of sustainably produced forest products

  2. Loggers use sustainable selective and strip cutting rather than clear-cutting

  3. Biodiversity researchers have called for more sustainable forest management

  4. Reduce road building in forests to remove logs

  5. Phase out government subsidies and tax breaks

  6. End logging in old-growth forests

  7. Place tree plantations only on already deforested land
• Some Rangelands are Overgrazed
• Deforestation and the Fuelwood Crisis

  1. Around 50% of the wood harvested yearly is directly burned for fuel or turned into charcoal fuel

  2. Trees are being cut 10-20 times faster than they are being replanted

  3. By 2050, the demand for fuelwood may be 50% higher than can be sustainably supplied

  4. To reduce the fuelwood crisis, fast-growing fuelwood plantations can be grown and more efficient wood stoves can be placed in underdeveloped countries

  5. Many people are trying to find ways to produce charcoal fuel without burning wood
• Causes of Tropical Deforestation

  1. Pressure from population and poverty

  2. Land is necessary for many reasons

  3. Global trade

  4. Agriculture
• We Can Improve the Management of Forest Fires

  1. The use of educational programs such as the Smokey the Bear campaign

  2. One way to improve fire management is through Prescribed Burns

  3. Allow some fires on public lands to burn

  4. Protect houses and other buildings in fire-prone areas by thinning the amount of trees

  5. Thin forest areas vulnerable to fires
• Tropical rainforests currently cover 6% of the world; they used to cover twice that percent. The loss began in 1950
• Several Ways to Reduce Tropical Deforestation

  1. Debt-for-nature swap: Countries can receive foreign aid or debt relief for protecting forest land

  2. Conservation concession: governments or organizations pay nations to conserve their resources

  3. Reforestation programs

  4. Consumers can buy recycled materials or only FSC-certified (Forest Stewardship Council)

  5. Green Belt Movement: plant 1 billion trees a year
• Rangelands


  • Unfenced grasslands that animals graze on
  • 42% are grazed
• Science Focus 10.2 - Certifying sustainably grown timber & products

  1. Maintaining the ecological and economic sustainability has been done through Selective Cutting since 1940

  2. SCS (Scientific Certification Systems) is part of the FCS (Forest Stewardship Council) formed to develop environmentally sound and sustainable practices for use in certifying timber & timber products

  3. Each year, the SCS evaluates Collin Pine’s landholdings and has consistently found that their cutting of trees has not resulted in damages to resources

  4. 5% of the world’s forest area in 80 countries has been certified according to FCS standards
• Managing Rangelands More Sustainably

  1. The most widely used method is to control the number of grazing animals and how long they graze

  2. Rotational grazing: cattle are confined by portable fencing to one area for a short duration of time

  3. Riparian Zones- Thin strips of lush vegetation

  4. Solution to Overgrazing- rotate animals/cattle away from overgrazed and damaged areas to allow for the restoration of the area

  5. Less widely used methods include the use of herbicides, mechanical removal, or controlled burning to suppress unwanted invader plants that grow in the place of wanted vegetation

  6. Cheaper way of removing unwanted plants: controlled, short-term trampling by large numbers of livestock (e.g., sheep, goat) destroys plant roots
• Rangelands


  • Unfenced grasslands that animals graze on
  • 42% are grazed by cattle, sheep, and goats
  • Study shows in 2050 it will increase to 70%
  • Blades of rangeland grow from the base. If eaten only at the top, it can remain renewable
  • Removal of vegetation helps boost regrowth and plant diversity
• National Parks Face Many Environmental Threats
• Protecting Wilderness Is an Important Way to Preserve Biodiversity
• Nature Reserves Occupy Only a Small Part of the Earth's Land
• Ways organizations pay nations to conserve resources

  • Reforestation programs
  • Consumer can buy recycled materials or only FSC-certified (Forest Stewardship Council)
  • Green Belt Movement: plant 1 billion trees a year
• Overgrazing

  • When grasses and roots become damaged
  • Reduces grass cover, exposes topsoil causing erosion by water and wind
  • Compacts soil making it hard to hold water
  • Caused a loss in 20% of the world's rangeland
• Uncontrolled urban development

  Can degrade aesthetic measures to reduce grazing
• Identifying and Protecting Biodiversity in Costa Rica
• Stresses on U.S. Public Parks
• Global Diversity hotspot is an area on earth especially rich in plant species that are found nowhere else and are in danger of extinction
• Protection of wilderness has grown by nearly 12 fold between 1964 and 2012, but this still isn't enough to sustain all species contained in these areas
• Conservative biologists


  Disagree with the opposition, stating that protecting wilderness and the preservation of biodiversity is more important to the long-term survival of multiple species
• The Ecosystems Approach

  1. Map land ecosystems and inventory species in them along with ecosystem services they provide

  2. Identify land ecosystems that can sustain harmful human activities and those that cannot (these need protection)

  3. Locate and protect endangered land ecosystems and species especially plant biodiversity and ecosystem services

  4. Seek to restore as many degraded ecosystems as possible

  5. Make development biodiversity-friendly by providing financial incentives (e.g., tax breaks) and technical help to private landowners who agree to help protect endangered ecosystems