Amazon

Where are rainforests globally

Where are rainforests globally

• appear on the equator - hot and humid

• Areas of low pressure - air rises quickly - lots of rainfall

Location of the amazon rainforest

Based around the amazon river

60% of the amazon is in Brazil - shared with 7 other South American countries

Based on the equator

The type of rainfall the amazon rainforest experiences

• Convection rainfall, the ground is heated quickly by the sun - water rises quicker forming mor rainfall

• Intense insulation

• Solar energy heats the land

• Air rises

• Forms cumulonimbus clouds

Size of the amazon

6 million km2 - double the size of India

Population of the amazon

47 million

Estimated number of trees

400 billion

Estimated amount of water released from trees

20 billion tonnes each day

Estimated carbon stored

150-200 billion tonnes stored in forest and soils

Estimated loss of rainforest

17%

Species

10% of known species on earth - a new species is found every other day

Water cycle in the amazon - Flows

• surface run off

• Infiltration

• Groundwater flow

  In the amazon temperatures range between about 23 and 33 degrees

  There is also no dry period in the amazon

  • However between June and October precipitation is less

Precipitation in the amazon

The amazon rainforest has 2000 mm of rainfall a year on average

• The main type of rainfall is conventional

• This is because there are high average temperatures caused by insulation

• Large amounts of solar energy are received

• This results in convection occurring as warm, moist air rises before cooling due to a diabetic expansion and condensing

Evapotranspiration in the amazon

Around 50-60% of precipitation in the amazon is recycled by evapotranspiration

• due to constantly high temperatures there are constantly high levels of both evaporation and transpiration

  • High soil moisture

  • Dense vegitation

Surface run off

Due to high levels of rainfall, huge amounts of water will run off into the amazon river and its tributaries

As soils in the amazon are well drained, this leads to rapid movement of water that infiltrates the soil and through flows to other channels

Water losses from the amazon are through

• The atmosphere as water vapour to other regions

• River flow to the Atlantic (westerly prevailing winds)

Stores in the water cycle in the amazon rainforest

• soil groundwater - deep soils, created by regular contributions of organic material, allowing water to infiltrate and be stored. Areas of permeable rock allow the formation of aquifers

• Vegetation - high levels of vegetation are key in absorbing, storing and transpiring water

• atmosphere - the atmosphere is a large store of water, in the form of water vapour and precipitation

How different types of geology effect run off rates

Areas where crystalline rocks are located run off will be more significant as the impermeable rock will keep the water on the forest surfacE (areas in the north and south of Brazil)

Areas with or unable rocks are more likely to encounter a lot more infiltration and less surface run off, allowing the water to soak into the ground. (Areas where permeable rock can be found are more central)

How the relief effects the flows of water in the amazon

• on the west due (Andes) to high relief rainfall and areas with a high gradient therefore increases the rates of lag time, surface run off, discharge and less infiltration and through flow

• most of the amazon is lowlands

The pantanol

• the pantanol is located in the south of the amazon rainforest on the boarder between Brazil and Bolivia - it is the worlds largest wetland area

• during the wet season 80% of the area is submerged

• During the dry season 20% of the area is submerged

How does temperature effect the water cycle

Evapotranspiration - water is lost from the plant due to high temperatures

Evaporation occurs more often - water rises to form clouds and therefore precipitate

The high temperatures leading to high levels of evapotranspiration and water stored in the atmosphere also play a key role in the formation of flying rivers. The flying rivers form due to the winds resulting in the movement of water vapour around the amazon

Upper Madeira basin flooding, April 2014

• largest tributary of the amazon river

• 19.68 m above normal levels at Porto Velho

• 60 deaths, 68,000 families evacuated, outbreaks of cholera

• Deforestation in Bolivia (2000-2012 = 30km2) and Peru - reduced water storage in vegitation, soils, permeable rocks and atmosphere = increased speed of run off

Amazon rainforest carbon cycle

• High NPP due to humid equatorial climate : 2500g/m2/yr

• Biomass carbon store : 400-700 tonnes/ha

• Large forest tresses store : 180 tonnes carbon/ha above ground, 40 tonnes in roots

• Soil carbon stores : 90-200 tonnes/ha

• 2.4 billion tonnes of carbon stored/per overall

• Amazonian rainforest accounts for 15/25% of all NPP in terrestrial ecosystems

Physical factors effecting carbon stores and flows

Forest trees : principle carbon stores, 100 billion tonnes locked up in rainforest, 1.7 billion tonnes released by decomposition per year. 60% of carbon stored above the ground in biomass

Decomposition : leaf litter and organic matter accumulates temporarily at soil surface but quickly broken down by decomposes due to warm, humid conditions

Geology : limestone acts a significant regional carbon store need the Andes

Human factors effecting carbon stores and flows

• pollution of water from oil spills = dead organisms = water is unusable for local people

• Extraction for residential/industrial purposes = lower water levels = less water taken up by plants = less evaporation = less clouds + rainfall = drier area

• 1 football pitch deforested every minute for farming, infrastructure, hydropower and oil exploration

• Less cooling effect from transpiration = climate change = 20% decline in rainfall predicted = effects on forest downwind

• Exhaust carbon biomass store as grasslands store less carbon and have lower inputs: 16.3 tonnes/ha biomass in rainforest

• Exposture to sunlight = fewer decomposers = slower rate of carbon return to the soil

• Loss of forest cover = biosphere carbon is replaced with atmospheric carbon

• Increase drought = increased fire risk = co2 released by combustion

• Cattle ranching and farming has led to deforestation = cattle release methane CO2

Stratagies for managing the TRF to protect carbon and water cycles

• Brazil has committed to restoring 120,000 km2 of rainforest by 2030

• Indigenous people have lived sustainably as hunter-gatherers and shifting cultivators for 1000s years in the amazon

• Exploitive colonial industries have upset this balance in he last 50 years

Protection through legleslation of large expanses of primary forest so far

1998 - amazon regional protected areas established, now covering an area 20x size of Belgium

44% of Brazilian amazon comprised national parks, wildlife reserves where farming is banned

Improved agricultural tequniques to make per infant cultivation possible

Farming = main source of deforestation in Amazonia but low fertility soils - unsustainable production = small holdings eventually converted into low quality grassland

Diversification = rotational cropping and combining livestock and arable

Human engineered soils