Deforestation and Management in the Amazon Flashcards
What is the number one cause of deforestation? What % does it account for? Any details?
=> Cattle ranching, 80% —> Forest needs to be converted to farmland.
=> 40 cows need 5 acres every 24 hours.
What is the number two cause of deforestation? How much is exported annually? How does it indirectly impact deforestation?
=> Soybean production.
=> 8 million tonnes.
=> Done mainly in southern fringes, but drives up land prices —> Displaces cattle ranchers who move to frontier areas (direct deforestation).
How and when does deforestation occur?
=> Primarily in August, the driest season. —> Farmers set fire to clear land for crops. Illegal land grabbers use fire to clear land quickly, often leads to wildfires.
=> Commercial agriculture - Large scale slash and burn. (Thousands of hectares burnt).
What has been the spatial pattern of deforested areas?
=> Formerly along rivers due to easier access, now along Trans-Amazonian highway.
=> ‘Arc of Deforestation’ along south-eastern edge of rainforest.
=> Policy changes regarding indigenous rights over land and development of remote regions have impacted rates. —-> 2021 peak at the deforestation rate. Agribusiness generates nearly a quarter of the country’s GDP.
Policies to deter deforestation?
=> Environmental Crime Act: Defined environmental crimes and strengthened IBAMA authority to crack down on illegal deforestation.
=> 2006 Soy Moratorium: Global commodities agreed not to purchase soy on land cleared after 2006.
=> Both contributed to: Deforestation fell between 2004-12.
=> 2009 Beef Moratorium: Cattle traders and beef producers agreed not to purchase beef illegally from deforested land.
=> Amazon fund established by President Lula for sustainable development projects. —> Allowing for conservation of rainforest and economic development.
=> BUT only 3% of environmental crimes in protected areas concluded by IBAMA.
Policies that encourage deforestation?
=> 1970s- Trans-Amazonian Highway: Built to help alleviate poverty, providing access to resources. Subsidised plots of land and improved accessibility attracted hundreds of thousands of migrants to move to the Amazon.
=> ‘Land grabbers’ sold land cheaply to poor farmers who cut down trees to build new settlement.
=> 2019-22: Bolsonaro: “Economic soul” of Brazil, free reign to agribusiness, mining, development. Weakened environmental protection and indigenous land rights. —> Pardoned environmental fines.
=> People can claim land if they occupy it for a year and ‘improve’ it.
=> Did not help initially to fight fires, allowed cleared land to be redeveloped. Only relented after international pressure. Norway and Germany halted donations to Amazon fund. France and Iceland threatened to sink EU’s trade deal with MERCOSUR.
=> 2022: Lula’s administration restarted the Amazon fund, with Norway and Germany pledging to restart donations.
Impacts of deforestation and farming practices on water cycle and flows?
=> FARMING: Soya plants and grasslands cannot recreate the continous canopy layer. —-> Reduced INTERCEPTION LOSS and LARGE-SCALE TRANSPIRATION. —-> More water reaches ground level and increses potential for saturation excess overland flows.
=> DEFORESTATION: Amazon releases 20 billion tonnes of water each days. Through larges scale transpiration (continous canopy) allows for significant cloud coverage. Deforestation disrupts this. —–> DRIER REGIONAL CLIMATE, e.g 24 days increase of dry season.
Impacts of deforestation and farming practices on carbon cycle flows?
.=> DEFORESTATION: Only second to burning fossil fuels as a source of greenhouse gas emissions. Amazon is absorbing less than 1/2 CO2 than it did 20 years ago. —-> Currently stores 120 billion tonnes of carbon. If cleared by fire, most of carbon will be released into the atmosphere enhancing greenhouse effect globally.
=> DEFORESTATION: If clearing cycle is shortened such as to 5-8 years, leads to unsustainable deforestation. —> Rainforest unable to recover, replaced by tough grasses. Carbon stored as biomass drastically reduced.
=> FARMING: Carbon stored as biomass is much less than trees (180 tonnes/ha). VS Soy: 2.7 ha/yr and grazed pastures (16.2 h/a). Soy production when harvested, disrupts soil. —> Releases CO2 into atmosphere. Grass and root not eaten by cattle. —-> Replenishes carbon into soil.
Impact of deforestation and farming practices on carbon in soil and nutrient cycle?
=> DEFORESTATION : Poor nutrients in the soil because input of nutrient cycle via leaf litter (nutrient cycling) has disappeared alongside forest trees.
=> DEFORESTATION: Loss of evergreen continous canopy removes interception loss as well as water recycling via transpiration. More rain reaches the ground surface and infiltrates into the soil, causing increased leaching of nutrients. —> Poor soils.
=> FARMING: Nutrients are depleted quickly for agriculture and cattle ranching. —> More deforestation, may spiral out of control.
=> FARMING: As soy is harvested it leads to limited leaf litter being left over to decompose and fertilise the soil. Manure from cattle ranching may help to replenish nutrients.
What are the four types of management strategies? Any examples?
- Better monitoring. : Use of remote sensing. DETER collects daily on deforestation, fire, vegetation health via satellites. Good? Clearing patches have reduced in size. Bad? Only detects large clearings, deforestation only detected once occured, increased forest clearing during rainy season when clouds obstruct satellite view.
- Improved law enforcement. : SMART software. Allows the community to monitor deforestation and register environmental crimes for public agencies to take action.
- More efficient farming practice, reforestation, carbon credit. : - - Reforestation of 2000 hectares in arc of deforestation. (Worth 85,000 cars annually).
- Agroforestry - Makes use of native trees, provides a sustainable food supply and income. Captures much more carbon than soy/ grassland.
- Carbon credits: Verified Carbon Standard Programme. Allows individuals and companies to offset emissions. Revenue generated reinvested, and provison of health services, education etc for communities. - Halting goods on illegally deforested land. : See Beef and Soy Moratorium.
