DELTAS ARE SINKING The world's fiver deltas Jake Up less than 0.5% of the Earth's land area, int they are home to hundreds of millions of people. With fertile soils and away access to the coast detan are important areas for food production. They also have unique ecosystems. Now many of the world's dellas are facing crisis. Sea levels are rising as a result of climate change, while dellas are sinking sadimente in deltar compact under their own weight, deltas naturally sink. If aft undisturbed, new river sediment can accumulate and help to maintain the delta surface above sea leval But dejtas are now subsiding much faster than they would do naturally. That's due to groundwater being pumped from aquifers (permeable rock) undemeath them and used to Irrigate crops and provide water for rapidly growing cilles. Under these conditions. only the continued deposition of sediment on deltas can keep them from 'drowning' Difficult decisions need to be made about development priorities, between countries upstream of dellas and those including the delias themselves. There will be trade-offs to be made between hydropower, agricultural practices and delte sustainability. Bures butos www.astatines.com/2018/01/ada/riva dalle changes threaten hundreds of milions 5.4.1 Where do deltas form? (1x1) (1) 5.4.2 What evidence in the extract indicates that deltas are densely populated? 5.4.3 According to the extract, how are cities disturbing the natural formation of deltas? Discuss the importance of protecting deltas. 5.4.4 5.4.5 (1x1) (1) (1x1) (1) (2x2) (4) A recent environmental impact assessment has highlighted concerns about the future sustainability of deltas. In a paragraph of approximately EIGHT lines, suggest strategies to protect areas like deltas from the negative impact of human activities​