The Water and Carbon Cycle - (The Amazon Rainforest) Flashcards
What percentage of South American Landmass does the Amazon rainforest cover?
40%.
What are the characteristics of the climate?
Hot and wet with very dense vegetation.
How many plant species, mammal species and fish species live in the Amazon rainforest?
1 million plant species.
500 mammal species.
200 fish species.
What are examples of endangered species in the Amazon?
The Amazon Manatee, Black caiman and the pirarucu.
What factor does the Atlantic ocean play in the wet environment?
There is lots of evaporation over the Atlantic ocean and this wet air is blown towards the Amazon.
How do warm temperatures in the rainforest effect precipitation rates?
High evaporation increasing the levels of precipitation.
Why is interception high and what does this do?
There is a dense canopy leading to high interception. As a result less water flows into rivers than might otherwise be expected and does it more slowly.
How does the water cycle effect the Amazon environment?
Means it is populated by species that are adapted to high humidity and frequent rainfall.
Is the Amazon rainforest a carbon sink?
Yes. It stores lots of carbon in its vegetation and soil making it a carbon sink.
What has the increased concentration of Co2 in the atmosphere in the Amazon rainforest led to?
Increased productivity as the vegetation is able to access more Co2 for photosynthesis. The amount of biomass has been increasing.
What has come as a result of the increased Co2 in the atmosphere in the Amazon and increased biomass?
The amount of Co2 being sequestrated by the rainforest has increased making it an even more important carbon store.
Whilst it has been suggested trees are growing more quickly what has also been found?
They are dying younger.
What does the trees in the Amazon dying younger mean?
That we may not be able to rely on the Amazon rainforest to continue to be such an effective carbon sink in the future.
What are the two main ways human activity has effected the Amazon rainforest?
Deforestation and climate change.
What are two of the main reasons for deforestation in the Amazon rainforest?
To exploit the timber or to use the land for farming.
What are the two main effects deforestation has on the Water cycle in the Amazon Rainforest?
In deforested areas there is no tree canopy to intercept the rainfall, so the water reaches the ground surface. This means there is too much water to soak into the soil. Instead this water moves to rivers as surface run off, which increases the risk of flooding.
Deforestation reduces the rate of evapotranspiration. This means less water vapour reaches the atmosphere, fewer clouds form and rainfall is reduced. This in turn reduces the risk of drought.
What are the effects of deforestation on the carbon cycle in the Amazon Rainforest?
Without roots to hold the soil together the heavy rainfall washes away the nutrient rich top layer of soil, transferring carbon stored in the soil to the hydrosphere.
There will be less leaf litter so humus will not be formed. The soil cannot support much new growth which limits the amount of carbon that is absorbed.
Trees remove Co2 from the atmosphere and store it, so fewer trees means more atmospheric Co2, which enhances the greenhouse effect and global warming.
What effects does climate change have on the Amazon Rainforest?
Can severely impact tropical rainforests.
In some areas temperature is increasing and rainfall is decreasing leading to drought. The Amazon had severe droughts.
Plants and amazon in tropical rainforests have adapted to moist conditions, so many species die in the dry weather. Frequent or long periods of drought could lead to extinction of some species. Droughts can also lead to forest fires which destroy large areas of the forest while also releasing Co2 into the atmosphere.
Scientists predict that a 4 degree temperature rise could kill 85% of the Amazon Rainforest. This would result in lots of carbon being released into the atmosphere as the dead material decomposes and less carbon being taken from the air by trees for photosynthesis.
When has the Amazon rainforest have severe droughts?
2005.
2010.
2015-2016.
What percent of the Amazon rainforest do scientist predict could be killed by a 4 degree temperature rise?
85%.
What are the four main attempts to limit human impacts on the Amazon?
Selective logging.
Replanting.
Environmental law.
Protection.
What is selective logging and how does it limit human impacts on the Amazon?
Only some trees (e.g. just the old ones) are felled - most are left standing.
Less damaging to the forest than felling all the trees in the area. If only a few trees are taken from each area the forest structure is kept. The canopy is still there and the soil isn’t exposed. This means the forest is able to regenerate, so the impact on the carbon and water cycle is small.
What is Replanting and how does it limit human impacts on the Amazon?
New trees are planted to replace the ones that are cut down. For example, a project in Peru replanted over 115 acres of forest between 2016 and 2019.
It is important that the same type of trees are planted that were cut down, so that the variety of trees is kept for the future and the local carbon and water cycles return to their initial state.
What are environmental laws and how do they limit human impacts on the Amazon?
Environmental laws can help protect rainforest. for example:
Laws that ban the use of wood from forests that are not managed sustainably.
Laws that ban excessive logging.
Laws that control land use, e.g. the Brazilian forest code says the land owners have to keep 50-80% of their land as forest.
What is protection and how does it limit human impacts on the Amazon?
Many countries have set up national parks and nature reserves to protect rainforests. For example the central Amazon conservation complex in Brazil was set up in 2003 and protects biodiversity in an area of 49,000km squared while allowing local people to use the forest in a sustainable way.
Within national parks and nature reserves damaging activities such as logging can be monitored and prevented.
