Forests Under Threat

• Leaching is where nutrients are washed out of the soil as water moves through.
• Weathering is the chemical break down of rocks that adds nutrients to the soil.
• The nutrient cycle is disrupted by:

  • the removal or destruction of biomes
  • heavy rain (which washes away litter)
  • deforestation (deforested areas are at higher risk of soil erosion)
• Deforestation causes higher risk of flooding and drought.
• Deforestation impacts the water cycle:

  • no trees = no interception, meaning rainfall is directly absorbed into the soil, causing faster soil erosion.
  • no trees = less infiltration, meaning lower ground water supplies, which is bad for people.
  • no trees = more surface runoff, meaning more soil erosion, meaning more water in rivers, meaning more flooding, causing more erosion.
  • more soil reaches the river, which takes up more space, increasing flood risk.
  • without shade, soil dries out faster, less evaporation and transpiration, meaning less clouds, less rain and more droughts
• Biomes store carbon as biomass (fauna and flora), when they die, they decompose and their nutrients (including carbon) are absorbed by and stored within the soil. This process is called sequestration and is the reason why biomes are such important carbon sinks (stores).
• Deforestation is cutting down the forest to use the wood/clear the land.
• A direct threat is a clear link between one thing happening and the damage being caused to something else.
• If we continue our rate of deforestation, the rainforest will be gone within 100 years. Fewer forests means increased speed of global warming. Rainforests contain 80% of habitats.
• Deforestation is caused by:

  • demand for land for agriculture
  • demand for wood/resources
  • mining
  • need for housing
• In Canada, the key causes of deforestation are: agriculture, oil and gas, and mining. In Brazil, the key causes of deforestation are: mining, pasture and fire.
• In Brazil, 63% of deforestation is due to cattle farming because Brazil has a nice climate for cows and their is a higher demand for meat.
• Causes of deforestation with examples:

  • Mineral exploitation, Coltan mining in the Democratic Republic of Congo is used for mobile phones
  • Hydroelectric Power, the Tucurui Dam in Brazil is used for mines by TNCs, it flooded 1750 km ^2 of tropical rainforest
  • Biofuels, palm oil is Indonesia has 6 million hectares of palm oil plantations with future plans for another 4 million.
• Direct Impacts of Global Warming:

  • If temperatures were to rise by 1 degree, 10% of land species would face extinction and Alpine, mountain and Tundra biomes would shrink
  • If temperatures were to rise by 3 degrees, 20 - 50% of land species would face extinction and fire risk on grassland would increase, flooding would cause loss of costal mangroves and bark beetles devastate coniferous forests.
• The rainforest is experiencing a decline in the amount of land being deforested because more awareness is being spread about the damage of deforestation, stimulating a surge in environmental protection and protected land, this means that it is more difficult to legally deforest the rainforest.
• Conservation is protecting biomes. (plants and animals). It can be isostatic or eustatic.
• There are two key rainforest conservation programmes:

  • CITES (Convention on International Trade in Endangered Species)
  • REDDs first project, Juma Sustainable Forest Reserve
• CITES conservation project:

  • ensures that trade doesn't threaten survival of endangered plants and animals
  • it is an agreement between countries and doesn't replace national laws
  • reduces the amount of trade by placing restrictions
• CITES is beneficial because it protects the species, however it does not protect the habitat, meaning deforestation continues. The agreement protects 34,000 species that are in danger of dying out, a key example being it has massively reduced the number of African Elephants being killed and the ivory trade.
• Conservation project, REDD:

  • the Marriot hotels are paying the locals to not cut down trees and report it if they see others cutting down trees. They are also buying the nuts from the locals to generate revenue and income. They pay 28 dollars a month to women of the household
  • this gives an alternative income to deforestation and selling timber
  • the REDD projects are paid for by governments in the country with deforestation or from a high income country / TNC
  • not entirely successful as South Asia still has high deforestation rates even though many countries there have signed up to REDD.
• Without protection, 60% of Juma's rainforest would have been gone by 2050, REDD protects a large enough area to support carnivores and larger primates, incomes have risen because of Bolsa Floresta payments. However Juma families rely on donations from the Marriot hotels and if funding stops, deforestation will continue.
• Ecotourism is educating visitors on the diversity of the forest and how it can be managed sustainably, providing employment for locals who would otherwise cut down the trees. For example, in Costa Rica people are offered tourism related jobs to provide an alternative income to deforestation.
• Afforestation is the opposite of deforestation, when trees are cut down, they are replanted to maintain the canopy.
• Agro-forestry is growing trees and crops at the same time. Allowing farmers to take advantage of the shelter from the canopy of trees.
• Costa Rico is conserving the rainforest through:

  • Agro-forestry
  • Selective logging
  • Education
  • Afforestation
  • Forest reserves and national parks
  • Monitoring
  • Eco-tourism