THE AMAZON RAINFOREST - CARBON WATER CYCLE

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CASE STUDY EXAM QUESTIONS

Actual Qs and Ans Expert-Verified Explanation

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-Guarantee passing score -10 Questions and Answers -format set of multiple-choice -Expert-Verified Explanation

Question 1: How the 'Water Cycle' affects the Amazon

Answer:

The water cycle causes the Amazon to be very wet - there is a lot of evaporation over the Atlantic Ocean, and the wet air is blown towards the Amazon. This contributes to the Amazon's very high rainfall.Warm temperatures mean that evaporation is high in the rainforest itself, which increases the amount of precipitation.The rainforest has a dense canopy - this means that interception is high. As a result, less water flows into rivers that might otherwise be expected, and it does so more slowly.The water cycle affects the Amazon's environment - it is populated by species that are adapted to high humidity and frequent rainfall.Question 2: Human activities in the Amazon affecting the 'Water Cycle' - Deforestation

Answer:

In deforested areas there is no tree canopy to intercept rainfall, so more water reaches the ground surface. There is too much water to soak into the soil. Instead the water moves to rivers as surface runoff, 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 increases the risk of drought.

Question 3: The Attempts to Limit Impacts on the Amazon - Replanting

Answer:

New trees are planted to replace the ones that are cut down. For example, Peru plans to restore 2.3 million hectares of forest by 2020.It's important that the same type of tree are planted that were cur down, so that the variety of trees is kept for the future and the local carbon and water cycles return to their initial state.

Question 4: The Attempts to Limit Impacts on the Amazon - Selective Logging

Answer:

Only some trees (e.g. the oldest ones) are felled - most are left standing.This is less damaging to the forest than felling all the trees in an 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.

Question 5: The Attempts to Limit Impacts on the Amazon - Protection

Answer:

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 49,000 km - sq whilst 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.

Question 6: The Amazon

Answer:

The amazon is a rainforest in South America, its the worlds largest tropic rainforest and covers 40% of the South American landmass.It has a hot, very wet climate and the vegetation is very dense.Many groups of indigenous people live in the Amazon. It's also home to 1 million plant species, over 500 species of mammals and over 2000 species of fish.The amazon is also home to many endangered species, including the Amazonian Manatee (an aquatic mammal), black caiman (a reptile) and the Pirarucu (a fish).

Question 7: The Attempts to Limit Impacts on the Amazon - Environmental Law

Answer:

Environmental Laws can help protect rainforests, 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 that landowners have to keep 50-80% of their land as forest.

Question 8: Human activities in the Amazon affecting the 'Carbon Cycle' - Deforestation

Answer:

Without roots to hold the soil together, heavy rain washes away the nutrient-rich top layer of soil, transferring carbon stored in the soil to the hydrosphere.Deforestation means that there is less lead litter, so so humus isn't 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.Question 9: Human activities in the Amazon affecting the 'Water & Carbon Cycle' - Climate Change

Answer:

Climate change can severely impact tropical rainforests. In some areas temperature is increasing and rainfall is decreasing, which leads to drought. The Amazon had severe droughts in 2005 & 2010.Plants and animals living in tropical environments are adapted to moist conditions, so many species die in dry weather. Frequent or long periods of drought could lead to extinction of some species. Drought can also cause forest fires, which can destroy large areas of forest, 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 decomposed, and less carbon dioxide being taken in from the air by trees for photosynthesis.

Question 10: How the 'Carbon Cycle' affects the Amazon

Answer:

The Amazon rainforest stores lots of carbon in its vegetation and soil, so it's a carbon sink.The increasing concentration of CO2 in the atmosphere has led to increased productivity in the Amazon because the vegetation is able to access more CO2 for photosynthesis - the amount of biomass has been increasing.As a result, the amount of CO2 sequestered by the Amazon rainforest has increased, making it an even more important carbon store.However it has been suggested that although trees are growing more quickly, they're also dying younger.As a result, we may not be able to rely on the Amazon to continue to be such an effective carbon sink in the future.