assess the potential causes + impacts of changes to the water balance within a tropical rainforest (20)

assess the potential causes + impacts of changes to the water balance within a tropical rainfo rest (20) conclusion= - - deforestation is causing changes to the ATR local water balance whereas enhanced greenhouse effect is causing global impacts upon the water balance with particular disruption to areas such as the ATR. - currently, these chan ges are being amplified through positive feedback loops - BUT, these loops can be mitigated through mitigation such as international initiatives such as REDD (but the current impacts may take some time to reverse) - in the future, the WWF state that by 20 30 if deforestation continues as it will over a quarter of amazon biome will be without trees so mitigation strategies are required now to remain within equilibrium introduction= - - water balance is the balance between the inputs and outputs in a system - any changes to these factors will change the dynamic equilibrium - Amazon rainforest (South America) is the world's largest tropical rainforest paragraph 1= - - deforestation for urbanisation (human) - 3.6 million hectares per year deforested - reduction in vegetation, decreases interception storage + vegetation storage/ decreasing potential evapotranspiration which ^ amount of precipitation reaching the ground at a rate exceeding infiltration capacity - canopy of ATR intercepts 88% of precipitation of w hich 36% is immediately evaporated into the atmosphere/ only 30% of water enters the river Negro (rest caught up in a constant closed system) - urbanisation (eg. Manaus) ^ amount of impermeable surfaces which ^ the risk of flash flooding which would impact on the indigenous people on a local scale - impacts are amplified as less evapotranspiration at a local scale and less water stored in biosphere ^ risk of vegetation drying out so more vulnerable to droughts + wildfires. -as shown through major droughts in the Amazon in 2000 and 2010 causing posi tive feedbacks - therefore, deforestation for urbanisation causes ^ of water stored in the biosphere rather than atmosphere - this is long -term as it disrupts the dynamic equilibrium paragraph 2= - - positive mitigation schemes on a global scale such as R EDD (reduced emissions from deforestation and forest degradation) - decreases the amount of forests cleared which helps to have the rainforest remain in a dynamic equilibrium - global scale initiative for rich countries to pay poor countries to not cut do wn trees - in 2009 Copenhagen climate talks $4.5 billion was pledged to support this idea