Amazon rainforest carbon and water

What are the annual yearly temperatures in the Amazon

25-30 degrees

how many GT/year of water is precipitated

13

How many GT per year of water is evaporated

7.2

What percentage of precipitation is recycled by evapotranspiration

50-60%

What percentage of rainfall is intercepted by trees

10%

what percentage of evaporation comes from intercepted rainfall

25%

How is convectional rainfall increased

Evaporation produces latent heat, which increases rainfall

How much water is evaporated annually?

8 trillion tonnes

How much water is lost annually to surface runoff

5.5 Gt

What is NPP

The amount of carbon retained in an ecosystem after respiration.

What is the NPP of the amazon

2500/g/m2/year

How much carbon is stored in the rainforest

100 billion tonnes

How much carbon does the amazon absorb per year

2.4 billion tonnes

the TRF is a carbon…

Sink - meaning it takes in more carbon than it releases

How much carbon is stored in above ground trees

180 tonnes per hectare

How much carbon is stored in the soil

200 tonnes per hectare

What proportion of global fossil fuels are absorbed by TRF

1/5

What are the 4 physical factors affecting the water cycle

• rock porosity

• Rock permeability

• Relief

• Temperature

How big is the amazon rainforest

6 million km

How many countries does the Amazon cover?

9

How much rain is there in the amazon year round?

2000mm

Why is there lots of surface run off in the amazon

High rates of rainfall, soil cant take all of it in - saturated overland flow

What is the NPP of the tundra

under 200g/m2/year

What does having a high NPP actually mean for the amazon

It indicates a rapid rate of biomass production - lots of growth, and so showing that the Amazon is a vibrant ecosystem with lots of growth.

How does temperature affect the water cycle?

• High temperatures = frequent and intense convectional rainfall

• Very high rates of evapotranspiration mean lots of recycling of water (50% of rainfall is returned by evap…)

Leeching is

Removal of minerals from soil by water moving down

Impact of relief on the water cycle in the amazon

Majority lowland, allows water to infiltrate more in gentle relief. Through flow main movement of water - some overland flow. Steeper areas near the feet of mountains have more overland flow.

Impacts of rock permeability on the amazon rainforest water cycle

Ancient shield rock is impermeable (metamorphic rock) - little percolation, and minimal storage capacity

Impacts of rock porosity on the water cycle

In areas with limestone (porous rock), rock can store rainwater & slow run-off rates.

Physical factors affecting flows and stores of the carbon cycle?

• Temperature

• Vegetation

• Organic matter in soil

• Mineral composition of rock

How does temperature affect the carbon cycle?

High temperatures allow for rapid nutrient cycle, and high biomass totals. Higher temperatures are catalysts for proccesses - decomposition and respiration, increasing the amount of carbon present

How does vegetation affect the carbon cycle

• Carbon is transferred via photosynthesis, terrestrial to atmospheric relationship

• Allows the TRF to become a carbon sink

How do the mineral composition in rocks impact the carbon cycle?

• Generally, the ancient shield of igneous and metamorphic rocks (not carbonate, so no impact)

• West Amazon has outcrops of limestone - store carbon

How does organic matter affect the carbon cycle

• Decomposers (bacteria and fungi) in the soil - promoted by humidity and temperatures. Nutrients released to the soil very fast, for uptake by trees. Decomposition releases CO2 into the atmosphere

What fraction of the rainforest has been lost since 1970

1/5

What are the main reasons for deforestation?

• Cattle pasture

• Housing

• Soybean farming

• Logging

• Roads

Impacts of deforestation on rainfall (madeira drainage basin)

• Less trees, less uptake from roots and less transpiration, meaning less rainfall and water storage in the atmosphere

• Removing trees decreases atmospheric humidity

• Low albedo of forest trees (dark green colour absorbs suns insolation.) Ground becomes more reflective, reducing temperatures as heat cannot be retained - reducing convectional rainfall.

What is the estimated decrease in rainfall if deforestation continues?

20%

Impacts on runoff from deforestation:

• Less interception and water storage within trees, and so more rain reaches the ground & faster. The intense rain reduces infiltration time, intensifying overland flow (shorter lag times)

In April 2014, what happened in the Madeira river?

Flooding

How high were discharge levels following the flood?

20m above normal

What are discharge levels?

The volume of water flowing through a river or stream at any given time

How many people were evacuated due to flooding?

68,000 families

What was the cause of flooding?

Deforestation in the upper basin (Bolivia and Peru), turning land into ranching and subsistence farming.

How is flood risk further enhanced due to deforestation

• Deforestation leaves soil weaker and more vulnerable to erosion

• Excess debris leads to sedimentation in rivers, reducing their discharge capacity and increasing flood risk

After deforestation, what percentage of rain goes straight to rivers rather than infiltrating?

50%

How much have rates of surface run off been increased

27 times

What is the above ground carbon biomass of grassland (the replacement of trees)?

16.2 tonnes per hectare , 1/11 of what it previously was.

What is the above ground carbon content of soy cultivation?

2.7 tonnes per hectare (almost 90x less)

How does deforestation impact carbon content in soils

Less leaf litter means a smaller carbon inout into soil

Pre deforestation, how much carbon was absorbed by photosynthesis

30.4 tonnes per hectare

10 years after deforestation, how much carbon was absorbed by photosynthesis

12.3 tonnes per hectare

post deforestation, how much carbon is stored in above ground biomass

12 tonnes per hectare

How are decomposers affected by deforestation

Soils with less carbon support less decomposers (need CO2), and so any leaf litter present is broken down slower and reduces carbon flow from soil to atmosphere

How does deforestation increase carbon transferred to the atmosphere

Slash and burn farming (mass combusting trees) emits excess amounts of CO2.

How is the nutrient cycle impacted by deforestation

Biomass is the principal store of carbon. Decomposition by fungi and bacteria mean as soon as leaves have fallen, nutrients are released for uptake, and the soil lacks nutrients. When the forest is removed, the nutrients are mainly removed and so minimal nutrients remain, explaining why it is difficult to regenerate a felled forest.

Nutrient cycle before deforestation (diagram)

Nutrient cycle after deforestation (diagram)

What are the three types of managements in the TRF

1. Protecting remaining forest through legislation

2. Reforestation projects

3. Improving agricultural techniques

In what year did the Brazilian government establish conservation areas

1998

What percentage of the Brazilian amazon is national parks (Banning farming)

44%

What is a limitation of protecting forest through legislation

Brazil can only monitor what is going on in their area of the Amazon, as it is a transboundary area. Therefore, other countries are not able to be controlled by them.

How big is Parica

1000km3

What is the 4th most affected reigon by deforestation in the amazon

Parica

What is the Parica project

20 million fast growing seedlings have been planted, with the aim of growth in 25 years. Financial assistance is given to farmers owning smallholders. This timber will eventually be felled and sold

What are the limitations of the parica project

A monoculture is maintained in the forest, and so biodiversity is not improved. The trees are felled after 25 years, not letting them grow to full carbon sink potential. Farmers are only interested when there is a monetary incentive.

Who are the Suruí

A tribe native to western amazon (brazil)

How do the Suruí help reforest?

By planting native seedlings in deforested areas around their villages. In time, these trees give them food crops and timber as well as income through selling timber.

In what year did the surui join the REDD scheme

2009W

What is the REDD scheme?

Reducing Emissions from Deforestation and Degradation - essentially, the UN pays people who reforest areas with carbon credits, and large corporations who have exceeded their carbon allowance purchase the tribes carbon credits with real money

What is shifting cultivation

Due to low soil fertility, an area cleared for cultivation can only be used for a few years till it is abandoned and farming moves somewhere else.

What happends to abandoned areas of land after cultivation

Used for cattle ranching

How bad is the quality of land after cultivation

They can only support one cow per hectare

What agricultural techniques are used to help soil quality

Diversification (or rotational cropping) - alternating the crops planted every few seasons.