• Deforestation
Reduces C store in biosphere and carbon fixation by photosynthesis. Increased soil erosion
declines soil C store. Forest trees transfer water by transpiration and reduced interception
increases run-off (20-30%) leading to flooding. E.g – The Amazon Rainforest Brazil, Madeira
Basin.
• Demand for water
Irrigation, industrial and domestic use has created water shortages. Largest US water
reservoir Lake Mead surface supplies diminished as more water is abstracted. In Bangladesh
over pumping of aquifers in coastal regions has led to incursions of salt water,
contaminating supplies.
• Acidification of oceans
Threatens biological carbon store by phytoplankton.
• Urbanisation
Reduces evapotranspiration from vegetation. Precipitation declines. Increased run-of and
reduced infiltration lowers water table.
• Fossil Fuels
Account for 87% of global primary energy consumption. Exploitation of coal and natural gas
has diminished geological C store, ¾ of coal plants in China and India due to rapid
industrialisation of economies.
