Earth's Life Support System pt 2- amazon rainforest Flashcards
What’s our case study of a tropical rainforest?
The Amazon rainforest
What’s the climate like in a tropical rainforest?
High average annual temperatures of 25-30 degrees.
Low seasonal variation in that temperature.
High average rainfall (no dry season)
What’s the average annual temperatures in a tropical rainforest?
25-30 degrees
What’s the average rainfall in a tropical rainforest?
2000mm
Why are there high average temperatures in a tropical rainforest?
As the sun shines directly over head with the concentration of the sun’s rays.
What type of rainfall is found in a tropical rainforest?
mainly convectional rainfall and precipitation all year round, due to intertropical convergence zone or low pressure belts dominating.
What does the intertropical convergence zone do?
It causes low pressure and rainfall all year round in the amazon rainforest. As it moves south to the tropic of Capricorn it may cause a smaller drier season in equatorial areas in the northern hemisphere.
What are the two different air masses for the intertropical convergence zone?
tropical maritime air mass
tropical continental air mass
What’s the tropical maritime air mass?
In tropical latitudes this air mass is hot to very hot, with high relative humidity, bringing unstable weather.
Where can the tropical maritime air mass be found?
Originates in the Atlantic ocean
What’s the tropical continental air mass?
In tropical latitudes this air mass is hot to very hot, with relatively low humidity, bringing stable weather.
Where can the Tropical continental air mass be found?
Originates in the Sahara desert.
What happens when the two air masses for the intertropical convergence zone meet?
moist air is forced upward, which causes water vapour to condense as the air cools and rises. This results in a band of heavy precipitation around the globe.
What are the flows in the amazon rainforest for the water cycle?
Precipitation
Evaporation
Run-off/ overland flow
What are the stores in the amazon rainforest for the water cycle?
Soils/ groundwater
Vegetation
Atmosphere
Precipitation in amazon rainforest water cycle:
High average of around 2000mm of rain per year. - 10% of that is intercepted by trees.
Convectional rainfall
Evaporation in amazon rainforest water cycle:
High evapotranspiration due to high temperatures, rainfall and dense vegetation.
50% of the incoming rain is returned to the atmosphere by evapotranspiration.
Run-off/overland flow in amazon rainforest water cycle:
Rapid run-off due to high rainfall.
River discharge peaks on one or two months per year.
Atmosphere in amazon rainforest water cycle:
High temperature means large amounts of moisture stored in the atmosphere, therefore high absolute humidity.
Vegetation in amazon rainforest water cycle:
Rainforest trees absorb and store water from the soil and release it by transpiration.
Soil/ groundwater in amazon rainforest water cycle:
Deep tropical soils/ high rainfall means large storage of water in soils or aquifers.
Where does the losses of water in the Amazon rainforest basin come from?
river flows out to the Atlantic ocean, and the export of water vapour to the atmosphere.
Where does the inward flux of moisture to the water system come from in the Amazon rainforest basin?
moisture from the Atlantic Ocean.
What percentage of carbon in land is stored in biomass in the Amazon rainforest?
40-50%
How much carbon is in the Amazonia?
14-40kg of carbon per km squared
How much biomass is in the amazon rainforest?
400-700 tonnes/ha
What does the Net Primary Productivity mean?
The amount of energy fixed (taken from the sun) that’s available for new plant growth.
What is the term for the amount of energy fixed (taken from the sun) that’s available for new plant growth?
Net Primary Productivity
What is the NPP in the Amazon rainforest?
2500g per m squared per yr
What is Net Primary Productivity measured in?
grams per metres squared per year.
How much carbon is stored in the soil of the Amazon rainforest?
between 90-200 tonnes/ha
What are examples of soil carbon?
fungi, microbes and decaying organic matter -> BIOTIC FACTORS
Minerals -> ABIOTIC
How much carbon does the Amazon rainforest absorb?
2.4 billion tonnes per year.
What type of soil does the rainforest have?
poor nutrient levels.
What are the key characteristics of the Amazon rainforest carbon cycle?
Rapid carbon exchange between the atmosphere, biosphere and soil.
Rapid and high levels of carbon fixing through photosynthesis.
Warm, humid conditions, so rapid decomposition and quick release of CO2.
What does rapid exchange enable in the carbon cycle for the Amazon rainforest?
enables the nutrient poor soils to support a diverse biome with high biomass.
What are the physical factors affecting the flows and stores in the water cycle for the Amazon rainforest?
Geology
Relief
Temperature
How does the geology affect the stores and flows in the Amazon rainforest?
In areas of the rainforest with permeable underlying geology, there is greater storage of rainwater and slow run-off.
Other areas of the rainforest have crystalline impermeable rock with minimal storage capacity and so high levels of run-off.
How does the relief affect the stores and flows in the Amazon rainforest?
Large parts of the Amazon basin are lowland areas so water will flow to streams and rivers as either overland flow or through flow.
What’s an example of rock that’s permeable in the Amazon rainforest?
Limestone
What’s an example of rock that’s impermeable in the Amazon rainforest?
granite
How does the temperature affect the stores and flows in the Amazon rainforest?
MORE WATER IS INVOLVED AS A RESULT
High rates of evapotranspiration due to the warmer temperature.
Strong convection resulting in high atmospheric humidity.
What are the physical factors affecting the flows and stores in the carbon cycle for the Amazon rainforest?
Climate- growing conditions
Biomass
Climate- decomposition rates
Geology
How does the climate-growing conditions affect the stores and flows in the Amazon rainforest?
Hot humid conditions with high rainfall and intense sunlight means high NPP due to high levels of photosynthesis.
How does the biomass affect the stores and flows in the Amazon rainforest?
Trees in the Amazonia are the principal carbon store; 100 billion tonnes are locked up here.
60% of carbon is stored in the above ground biomass, with the rest in the soil.
How does the climate- decomposition rates affect the stores and flows in the Amazon rainforest?
Decomposition is rapid due to hot, humid conditions.
Soil organisms decompose organic matter releasing nutrients, taken up b y trees and return CO2 to the atmosphere.
How does the Geology affect the stores and flows in the Amazon rainforest?
Much of the Amazonian basin consist of igneous and metamorphic rocks.
Close to the Andes limestone outcrops are found which is a significant carbon store for the slow carbon cycle.
How much do estimates suggest of the primary rainforest has been lost in the Amazon in the last 50 years?
Nearly 20%
How much does the Amazon rainforest cover?
An area of more than 6 million km.
How much of the precipitation in the Amazon Basin is from evapotranspiration?
About 1/3 of the precipitation
How does deforestation affect the water cycle for evapotranspiration?
Reduced evapotranspiration reduces the humidity in the atmosphere so more solar radiation is reflected, increasing temps.
How does deforestation affect the water cycle for surface run-off?
There’s more river discharge as the soil is impermeable so overland flow occurs.
How does deforestation affect the water cycle for the biotic pump?
The more radiation that is reflected reduces the biotic pump which reduces the low pressure zone as there is less moisture so less precipitation.
What is the biotic pump in the Amazon Rainforest?
Suggests that some forested areas can create the conditions that lead to heavy rainfall and that rather temperature differences bring precipitation over land and condenses.
What are flying rivers?
Wind travelling from oceans to land which has moisture.
How much water is created by flying rivers?
20 billions tonnes per day
How are winds created in flying rivers?
Air pressure is lowered as large amounts of water vapour condenses and air flows from places of high pressure to low pressure.
What type of feedback does flying rivers enable?
Positive feedback
What is the case study of how human activity has modified the water cycle in the Amazon Rainforest?
The Madeira Drainage Basin
What is the size of the Madeira Drainage Basin?
2x the size of Spain
900,000km squared
How long is the Madeira river?
3,380km
When did the Madeira river reach record heights?
In April 2014 which caused the worst flooding to occur in centuries.
What were the effects of the Madeira flooding in 2014?
Huge area of the floodplain was inundated
60 deaths
68,000 evacuated
Cholera outbreak also occurred.
What were the changes to the store in the Madeira Basin?
Trees
Soil
Permeable rocks
Atmosphere
What were the changes to the flows in the Madeira basin?
Less evapotranspiration as there are fewer trees.
Less precipitation as there’s less evapotranspiration.
What was believed to be one of the main drivers for the Madeira flooding?
Deforestation in the Andean Highlands of Bolivia and Peru.
Why was the Andean Highlands deforested in the Madeira Basin?
For farming and cattle ranching.
What are the impacts of deforestation?
Soil erosion increases which reduces the rivers capacity.
Can lead to permanent climate change as it can break the water cycle.
In a typical year, how much CO2 does the amazon absorb?
2.3 billion tonnes
In a typical year, how much CO2 does the amazon emit?
1.9 billion tonnes
What are the human factors that affect carbon and nutrient flows and stores in the Amazon rainforest?
Deforestation
Why is there a reduction in the carbon store because of deforestation for farming?
Agriculture and pastureland hold far less carbon than forest trees.
Why is there a reduction in the carbon store because of deforestation for selective logging?
Selective logging of mahogany can result in reduction of carbon store as the gaps which are opened in the forest means areas are more exposed to wildfires .
How much less carbon is stored when the forest shrubs grow in the primary forests place?
40% less than the primary forest.
How does deforestation affect the nutrient cycle?
The store is destroyed as trees are removed.
Nutrient flow is broken down and not taken up by the roots.
Nutrients are therefore washed away by rainwater.
Soil erosion further reduces the nutrients.
How can the rainforest be managed more sustainably?
There are 3 categories of management strategies:
Protection of remaining primary forest
Reforestation
Improving agricultural techniques
What are the 3 categories of management strategies to manage the rainforest more sustainably?
Protection of remaining primary forest
Reforestation
Improving agricultural techniques
What project has been aiming to protect the remaining primary forest?
The Amazon Region Protected Areas Programme (ARPA)
When did the ARPA project start to aiming to protect the remaining primary forest?
2003
What is the ARPA project a part of a pledge made?
A pledge made by the Brazilian government in 1988 to triple the area of Amazon under legal protection.
Whose involved in the ARPA?
Government agencies
Non-government organisations such as WWF
How is the ARPA financed?
A protected areas trust fund controlled by the world bank and Brazillian Biodiversity fund.
What are the aims of the ARPA?
Establish new protected areas for strict conservation.
Establish sustainable use reserves where local communities have a stake.
What are the successes of the ARPA project so far?
There’s been a 75% decrease in Brazil’s deforestation from 2000 to 2012.
1.4 billion tonnes of CO2 emissions have been avoided from deforestation.
What are the two projects for reforestation?
Parica project- Amazonia
REDD
What is the Parica project?
A sustainable forestry scheme that aims to develop 100km squared of commercial timber plantation on government-owned deforested land.
How does the Parica project for reforestation work?
To plant 20 million fast growing tropical hardwood seedlings on 4000 smallholdings to mature over 25 years.
How long does it take for a hardwood seedling to grow for the Paric project?
25 years
What is given to the smallholders within the Parica project when the seedlings are growing into trees?
financial assistance is provided for land prep, planting and maintenance.
Why is the Parica project sustainable?
Sequesters carbon in trees and soil.
Reduces CO2 emissions from deforestation.
Re-establishes the carbon and water cycles.
What is the strength of the Parica project?
It is sustainable.
What is the weakness of the Parica project?
It doesn’t replicate the biodiversity of a primary forest as it is monoculture.
What does monoculture mean?
only one type of plant so less diverse
What does the REDD project for reforestation stand for?
Reducing Emissions from Deforestation and Forest Degradation
What is REDD?
A project to try to tackle the issue of deforestation and forest degradation
What does REDD encourage?
It encourages developing countries to reduce their emissions and enhance the removal of greenhouse gases through a variety of forest management options .
Who were the first group of people to implement a major forest conservation and carbon storage offset by selling carbon credits?
The Surui people in Rondonia.
Who are the Surui people?
An indigenous group who became the first to implement a major forest conservation and carbon storage offset by selling carbon credits.
Where can you find the Surui people?
In Rondonia
What group are the Surui people apart of?
REDD
What are the Surui paid to do by REDD?
Paid to protect the rainforestand abondon logging.
What are the Surui people granted?
Granted carbon credits which can be purchased by international companies who have exceeded their carbon limits.
What is an example of an organisation buying carbon credits off the Surui tribe?
In 2013, Natura which is a Brazilian cosmetics giant bought 120,000 tonnes of carbon offsets.
What are the successes of the REDD project with carbon credits?
In the early years the project dramatically reduced deforestation within the area during its first 5 years.
Illegal logging in indigenous territory dropped to almost zero from 2009-2012.
What is the weakness of the REDD project?
It was suspended in 2018after the discovery of large gold deposits in the area which sparked in a surge in deforestation.
What has the suspension of the REDD project been blamed on?
The lack of law enforcement in the territory and the arrival of powerful self-interested groups.
What are the improved agricultural techniques?
Combining livestock and arable operations.
Rotational cropping.
A focus of planting perennials.
What does it mean when we combine livestock and arable operations?
Putting them together.
What does arable operations mean?
Plant operations
How is rotational cropping beneficial?
It helps to maintain fertility to the land and prevent soil exhaustion.
What is rotational cropping as a improved agricultural technique?
When we change the crops on a certain area each time as they all take different nutrients.
What are examples of perennials?
Banana
Cacoa
coffee
rubber
What have been one of the main reasons for deforestation?
Agriculture
Why will a small holder move on after only a few years of having that section of land?
Because it has become infertile and so fell more trees in a different area.
