ELSS- Amazon CS

Question 1

Where is the amazon located?

Answer 1

The amazon covers a range of countries such as Brazil, Columbia, Venezuela, Peru and Bolivia and they are all found in Northern and Central South America

Question 2

What are some general facts about the Amazon?

Answer 2

-The area of the Amazon is 6,000,000 km squared
-The length of the amazon river is 6,700km
-50% of tropical rainforest in the world is found in the Amazon
-The % of forest lost to deforestation since 1970 is 20%
-25% of carbon in biomass is stored in the Amazon

Question 3

What is the climate of the Amazonia?

Answer 3

-Roughly 26°c in winter and 27.5°c in summer. Extremely high all year round
-Annual rainfall is high specifically within winter.

Question 4

Why are the highest levels of solar insolation on the equator? (2 reasons)

Answer 4

1-Curvature of the earth: As the sun is directly above the equator the rays are extremely concentrated on the equator. At the poles the suns rays are at an angle causing the radiation to be spread out and less concentrates
2-Thickness of the atmosphere: As the sun is located above the equator the rays have to travel through less of the atmosphere, so less is reflected by the atmosphere

Question 5

Why does the tropical rainforest have so much rainfall?

Answer 5

-The tropical rainforests are found on the rising limb of the Hadley cell
-At the equator the air is rising due to intense levels of incoming solar radiation
-As the air rises it cools with altitude and condensation takes place to form clouds
-When enough condensation has occurred for the mass of liquid water in the cloud to overcome gravity it will fall as rain
-We call this type of rainfall convectional relief

Question 6

What is the process of convectional rainfall?

Answer 6

1-As air cools at the DALR it is not able to hold as much water in gaseous (vapour) form and it approaches dew point.
2-Water condenses as clouds, particles collide until rain droplets form.
3-Rising air creates a zone of low pressure on the surface around the equator.
4-Air rises, expands and cools
5-Convectional rainfall falls in large amounts at the equator, therefore making the growth of tropical rainforests possible
6-Equator receives high amounts of solar insolation and therefore heat
7-Heat from Earth’s surface causes air above to warm and rise

Question 7

Why is there still some variation in rainfall and temperature?

Answer 7

-The earth is tilted relative to the sun – by 23.50
-In June, the Northern Hemisphere is tilted towards from the sun
-The most intense heating (sun directly overhead) from the sun moves to north of the equator toward the Tropic of Cancer
-This causes the ITCZ (Inter-Tropical Convergence Zone) to also move north
-The opposite occurs in December

Question 8

What are the characteristics for the atmospheric, land and biomass stores of water in the tropical rainforest?

Answer 8

1-Atmosphere - amazon rainforest has a large sum of clouds and it stores more moisture in the air.
2-Land - precipitation and soil moisture soil. So much water percolates and leaches nutrients from the soil.
3-Biomass - extremely large

Question 9

What are the characteristics of flows for the atmosphere, land and biomass in the amazon rainforests water cycle?

Answer 9

1-Atmosphere - Large amount of precipitation and evaporation in the water cycle
2-Land - Large amounts of water are evaporated off. Large amounts of interception and little surface runoff. Lots of infiltration as tree roots guide water into the soil
3-Biomass - lots of transpiration and respiration due to tones of vegetation

Question 10

What are the inputs into the Amazon basin for the water cycle?

Answer 10

-Winds are westerly blowing warm, moist air from the Atlantic Ocean
-Most of the rain from the ocean is released near the coast though some continues inland
-The Pacific ocean has a cold ocean current running down South America so little evaporation takes place (so not an input of water to this system)
-The Amazon river runs for 6,700km through the rainforest.
-Evaporation takes places from the water in the river as well making it another large input of water to the system
-The large number of trees means there is a lot of evapotranspiration as well
-The Andes on the west coast encourage precipitation on their eastern flank meaning that water will mainly run east wards into the rainforest river catchments and back into the Atlantic rather than the Pacific on the west

Question 11

What are the outputs from the amazon rainforest basin in the water cycle?

Answer 11

-Water is heated and evaporates into the atmosphere and it then gets carried into over regions by winds
-Water is heated and evaporates over the amazon basin
-Water is recycled within the amazon rainforest
-Surface run off into the amazon river results in losing a huge amount of moisture which flows into Atlantic

Question 12

What are the characteristics of precipitation in the amazon water cycle?

Answer 12

High, average totals (>2000mm). Evenly distributed throughout the year though short drier season in some places. High-intensity, convectional rainfall.

Question 13

What are the characteristics of interception in the amazon water cycle?

Answer 13

This is high (around 10% of precipitation) and intercepted rainfall accounts for 20-25% of all evaporation

Question 14

What are the characteristics of evapotranspiration in the amazon water cycle?

Answer 14

-High rates of this due to high temperatures, abundant moisture and dense vegetation
-Strong evapotranspiration-precipitation feedback loops sustain high rainfall totals
-Around a half of incoming rainfall is returned to the atmosphere by evapotranspiration
-Moisture lost in transpiration is derived from the soil via tree roots

Question 15

What is the run off like in the Amazon water cycle?

Answer 15

-Rapid related to the high rainfall, intensive rainfall events and well-drained soils
-Depending on seasonal distribution of rainfall, river discharge (stream flow) may peak in one or two months of the year

Question 16

What are the physical factors affecting the water cycle?

Answer 16

-Geology
-Relief
-Temperature

Question 17

How does geology effect the water cycle?

Answer 17

-Impermeable catchments (Guiana shield & Brazil shield surrounding the amazon basin) have minimal water storage capacity resulting in rapid run-off over the area of more permeable rock
-In periods of heavy rain, groundwater stored becomes saturated, increasing chances of flooding
-Due to different geology’s across the rainforest different places will have varying rainfall

Question 18

How does relief affect the water cycle?

Answer 18

-Flat land surrounded by higher relief meaning land acts as a funnel across the width of South America
-In areas of gentle relief water moves horizontally through the soil to the rivers giving time for infiltration and percolation
-In the west, the Andes create steep catchments with rapid run-off
-This reduces infiltration and increases overland flow (the west is more likely to flood)

Question 19

How does temperature affect the water cycle?

Answer 19

-High temperatures and thermal energy throughout the year generate high rates of evapotranspiration (large atmospheric store)
-Convection is strong leading to high humidity and intense precipitation

Question 20

Which physical factors is the largest spatially and temporally?

Answer 20

Temperature is the largest spatially and geology is the largest temporally?

Question 21

Where is the Madeira river located?

Answer 21

Madeira river basin within the eastern Bolivian lowlands, on the Brazilian shield

Question 22

when did the flood occur at the Madeira river?

Answer 22

22nd May - mid June 2014. One of the worst floods on record

Question 23

What factors caused the flooding at Madeira river?

Answer 23

-Deforestation & Jrau and Santo Antonio hydroelectric dams. Converting forest into grassland makes the quantity of water that runs into rivers x26.7 and soil erosion by 10.8x. (human)
-Large parts of flatlands are flood plains even in normal rainfall, extremely high rainfall, Brazilian shield (physical)

Question 24

What were the social impacts of the flood?

Answer 24

-Affected more than 300,000 people
-More than 60 people died in Bolivia
-Fast spread of bacterial infections
-Many lost their houses (wooden bungalows)
-The population lived with polluted water for more than 40 days inside their homes

Question 25

What were the economic impacts of the flood?

Answer 25

-The flooding of the Rio Negro caused losses more than $200 million
-Water remained high adn inside homes in poor areas of Manaus for over 50 days
-Flooding usually occurs in 10-year cycles however here it takes 3 years

Question 26

Lowest to highest layer of tropical forest?

Answer 26

1-Shrub layer
2-Under canopy
3-Main canopy
4-Emergent layer

Question 27

What is GPP and what is it like in the Amazon?

Answer 27

This is the gross primary productivity and it is the amount of carbon removed from the atmosphere by plant photosynthesis. There is always high carbon fixing and a high GPP all year round. 25T/ha/yr

Question 28

What is NPP and what is it like in the Amazon?

Answer 28

This is the net primary productivity which is the amount of energy made available by plants to animals. The rainforest overall gas a positive flux all year round greater than the transfer from atmosphere to biosphere. 2200 g/m2/yr

Question 29

What are the Amazons stores like in the nutrient cycle?

Answer 29

-Large biomass
-Small soil but larger than litter
-Litter is very small

Question 30

What are the Amazons flows like in the nutrient cycle?

Answer 30

-Large uptake pathway between biomass and soil
-Large weathering and leaching from soil
-Large decay pathway between soil and litter
-Medium precipitation and runoff from litter
-Very small fall out pathway between litter and biomass

Question 31

How does the Amazons carbon cycle differ to others around the world?

Answer 31

1-Relatively high NPP - a lot of carbon is stored in vegetation each year through growth. More is absorbed through photosynthesis than is respired. Rapid flux of photosynthesis, decomposition and respiration. Climatic conditions support high amounts of vegetation.
2-Less carbon stored in soils than other ecosystems. Organic matter is quickly decomposed, mineralised and recycled so less carbon storage in soil than other ecosystems.
3-Faster decomposition due to climatic conditions.
4-High rates of photosynthesis.
5-Rapid exchanges between biosphere and atmosphere

Question 32

What are some facts about the carbon stores in the Amazon?

Answer 32

-Forest trees dominate the biomass and are the main carbon store
-100 billion tonnes of carbon is locked up in the amazon rainforest
-60% of rainforest carbon is stored in the above ground biomass of tree stems, branches and leaves (remainder is below ground, mainly as roots and soil organic matter)
-Decomposition releases 1.7 billion tonnes of CO2 per year in the Amazon basin
-Leaf litter and other dead organic matter accumulates temporarily at the soil surface and high temperatures and humidity promote rapid decomposition of organic litter by bacteria, fungi, and other soil organisms

Question 33

What are some facts about the carbon flows in the Amazon?

Answer 33

-2.4 billion tonnes of CO2 is absorbed a year by amazon
-1.7 billion tonnes of CO2 is released a year by decomposition
-Rainforest is a very important global sink
-Photosynthesis connects the rainforest to the atmosphere carbon stores
-High temperatures, high rainfall and intense sunlight stimulate primary production - photosynthesis (NPP averages about 2200grams/m2/year
-Amazonia alone accounts for 15-25% of all NPP in terrestrial ecosystems
-Decomposition releases nutrients to the soil for immediate take-up by tree root systems, and emits CO2 which is returned to the atmosphere

Question 34

What are the human factors in the Amazon affecting the water cycle?

Answer 34

-50% of the amazon could become degraded savannah if the climate changes
-In the last 50 years deforestation has made its way to about 20% of the amazons vegetation
-4/5 of deforested land has been converted into pasture for cattle farming

Question 35

What are the human factors leading to deforestation and changes in the Amazons water and carbon cycle?

Answer 35

Fires, mining, oil and gas exploitation, hydroelectric dams, crop and cattle farming, agriculture, deforestation.

Question 36

What are the Impacts of deforestation on stores and flows of water cycle in the Amazon?

Answer 36

Height of trees have halves and the canopy has been removed. (Change)
- increase in the washing away of the organic layer, decrease in interception by drip tip and increase in surface run off (impact)
Trees that have been cut down will have maintained air moisture by evapotranspiration (change)
- warm and damp conditions will be lost slowing down decomposition rates and precipitation which is crucial for trees to survive (impact)
Trees cut down being removed or cut down (change)
- would have aided infiltration to maintain soil moisture. The soil moisture store is reduced and the biomass store is reduced (impact)

Question 37

What are more impacts of deforestation on stores and flows of the water cycle in the Amazon?

Answer 37

Outputs through evapotranspiration: There are less trees in the rainforest meaning that evapotranspiration cannot take place at the same rate due to limited surfaces, this results in increased run off which can result in the soil becoming saturated and can cause flooding

Ø Recycling of rainfall: As evapotranspiration slows, the rate at which water is being inputted into the system, is faster than the rate that it is leaving resulting in increased run off and saturated soil

Ø Infiltration: Increased absorption of solar energy at surface and higher temperatures

Ø Surface runoff (and as an output):

Ø Interception: As the canopy layer is removed, less interception occurs which can result in the rate rainfall is input into the soil increasing

Ø Cloud formation: Clouds will form less as the rate of evaporation/evapotranspiration reduces which can lead to less precipitation and therefore drought

Ø Soil moisture storage (remember there is less organic material on the surface to hold moisture): The soil moisture storage is reduced and there is less organic matter which means increasingly creating conditions more likely to flood and environment drier

Question 38

What are the effects on the carbon cycle of switching from forest to Greenland?

Answer 38

-Increases run off by 27 times
-Half of all rainfall goes directly into rivers

Question 39

What are the effects on the water cycle through the removal of trees?

Answer 39

-Less water taken out of soil and transferred to the atmosphere through transpiration
-Less interception so more falls directly on the soil
-Trees stabilise albedo and ground temperatures
-Stops contributions to atmospheric humidity and affects cloud formation and condensation - impacts on climate change
-Increased run off which contributes to soil erosion especially as tree roots are not present to hold matter together (links to carbon cycle)

Question 40

What are the further changes and effects on the carbon cycle within the Amazon?

Answer 40

Switch from forest to soya cultivation ~ Carbon stored drops to 2.7 tonnes/ha.

Burning of trees to clear land for farming ~ Carbon returned to atmosphere store - long term impacts on NPP.

Switch from forest for grassland (usually for cattle ranching) ~ Carbon stored drops to 16.2 tonnes/ha. This is a very small amount of carbon compared to trees. It exhausts the carbon biomass store of 180 tonnes/ha.

Removal of biomass store of nutrients through logging ~ Fewer nutrients available overall in ecosystem. Soil exhausted of nutrients through leaching (from rainwater hitting the soil directly rather than being intercepted) and vulnerable to erosion by run-off. Soils without protective cover of trees are quickly eroded by run-off. Main nutrients ~ Potassium, magnesium and calcium.

Removal of trees that photosynthesise. ~ Long term changes to NPP - carbon usually returned to atmosphere if biomass is burnt (combustion) or left to decompose.

Removal of input of organic matter to soils ~ Soil is depleted of carbon and cannot return as much carbon to atmosphere as it also doesn’t support decomposers as strong sunlight. Depleted of carbon, exposed to strong insulation, support fewer decomposers organisms, thus reduce flux of carbon to atmosphere.

Question 41

What is the overall impact of afforestation on the forest?

Answer 41

Biodiversity is constantly being reduced and monoculture is encouraged however it is economically and socially sustainable as locals can continue to benefit through resources the rainforest supplies

Question 42

What is the overall impact of afforestation on the water cycle?

Answer 42

Increases evapotranspiration, infiltration and interception. Reduces surface runoff and therefore maintains the nutrients left in the soil.

Question 43

What is the overall impact of afforestation on the carbon cycle?

Answer 43

Sequesters carbon in trees and vegetation. New plants can take in the carbon that was once emitted due to deforestation.

Question 44

What are some facts about afforestation in the Amazon?

Answer 44

-EG: Patricia Project (1000km^2 of sustainable forestry on government land) - not on large enough scale
-Landowners are paid to preserve and restore the forest

Question 45

What is the overall impact on forest of improving agricultural techniques?

Answer 45

Successful for soil regeneration as more nutrients can infiltrate the soil. Doesn’t stop that eventually soil will be depleted anyway. Contour row crop systems - has some effect but doesn’t eliminate the fact that soil will eventually be depleted.

Question 46

What is the impact on the water cycle of improving agricultural technique?

Answer 46

Increase in biomass reduced overland flows. Planting crops perpendicular to a hill side reduces soil erosion and water performing surface runoff which reduces nutrients. An increase in storage capacity for the soil reduces the amount of saturated overland flow.

Question 47

What is the impact on the carbon cycle of improving agricultural technique?

Answer 47

Increase in the biomass store reduces the atmospheric store which is needed as a result of previous deforestation.

Question 48

What are some facts about improving agricultural technique?

Answer 48

-Farming is the reason for 4/5ths of deforestation
-Plantations reduce the NPP from 180T/ha to 3T/ha

Question 49

What is the overall impact on the forest of the protection of remaining forest?

Answer 49

Maintains the rainforests biodiversity and natural habitats for animals. Protects interlinking relationships between plants and animals. However this causes the economy to suffer as the locals can’t benefit off the rainforests resources.

Question 50

What is the impact on the water cycle of the protection of remaining forest?

Answer 50

-Maintains the rate of evapotranspiration.
-Maintains surface runoff or overflow as roots allow water to penetrate the soil and maintains interference.

Question 51

What is the impact of the carbon cycle of the protection of remaining forest?

Answer 51

Maintains the amount of CO2 trapped in vegetation and trees - as they aren’t cut down large masses of CO2 aren’t released into the atmosphere.

Question 52

What are some facts about the protection of remaining forests?

Answer 52

-Brazil spends $50m a year protecting its protected areas
-Over 44% of the Amazon is not protected

Question 53

How much carbon is held in peat bogs?

Answer 53

Could be up to 90% in the amazon

Question 54

What are the benefits of biodiversity on the stores of the carbon cycle?

Answer 54

-Stores more carbon than any other terrestrial ecosystem
-As trees grow larger, they develop more biomass which contains carbon

Question 55

What are the Benefits of biodiversity on the flows of carbon?

Answer 55

-High flux of carbon from stores in soil due to high decomposition and uptake from trees

Question 56

What are some key facts and figures about biodiversity in the amazon?

Answer 56

-1% of tree species store 50% of the Amazon’s carbon
-The Amazon is home to an estimated 16,000 tree species - 182 are hyperdominant
-The Amazon covers an estimated 5.3m km2 and holds 17% of global terrestrial vegetation carbon stock

Question 57

What are some facts about flows of water in the Amazon?

Answer 57

-River has a discharge of 750,000km^3 a year
-2000mm of rain a year
-50% or precipitation recycled
-10% of rain is intercepted, which contributes to 25% of evaporation
-A single tree can release 1000L of water a day, and there are 3 billion trees

Question 58

What are some facts about water stores in Amazon?

Answer 58

-20% of worlds flowing fresh water
-50% of tree is made up of water, and there are 3am trees