Trees and coastal cities’ defenses
Responding to disaster using trees, as a part of disaster preparedness
Interesting research is being done on tree planting in some of the world’s cities, exploring the many benefits from doing this. In general terms, trees help to ‘clean’ air by removing carbon dioxide and releasing oxygen into the air, they can cool the air through evaporation and can prevent erosion and save water, depending on the careful selection of useful trees. Tree planting can have huge social benefits too. The coastal city of Miami, Florida, is exploring tree planting because the city’s location at sea level and tendency to experience tropical monsoon, make it vulnerable to the impacts of climate change, such as coastal flooding. Trees help minimize flooding by absorbing the force of water and acting as a barrier between storm surges and homes near the shoreline.
What was also noticed in Miami, USA, was the limited number of trees in the city’s under-served neighbourhoods, a common occurrence in many cities. Research showed this lack of tree canopy can impact academic performance, crime rates, personal health and even increased illness and death from extreme heat and poor air quality.
The full suite of benefits range from things like raising quality of life standards, promoting safe, resilient construction, restoring degraded land, training communities on environmental protection and at a higher level informing green policy and Sustainable Development Goal objectives. However, there are more grim aspects to tree planting, notably to soak up the excess of carbon dioxide and try and avert the full climate change suite of horrors, and to restore degraded forests and scrub lands so that they can once again act to absorb the impact of cyclonic rainfall and prevent the worst floods.
Tree planting and atmospheric carbon
The movement to grow large numbers of trees as a form of environmental remediation has been growing over the last 20 years, notably since the highly public and successful work of Nobel Prize winner, Wangari Maathai in Kenya. Currently, many large corporate agencies (Coca Cola and Timberland ) have been promoting this as a good use of Corporate Social Investment (CSI), team building, and contributing to useful climate change projects, for example, Timberland’s goal of planting 50 million trees globally.
‘Green Wall’ tree planting schemes to stem the movement of the deserts
- In China, the desert sands have been moving and creating dust pollution many miles away. China’s Great Green Wall has been a work in progress for many years, to stop the advance of the Gobi desert.
- In the Sahel region of Africa, the Sahara desert sands are moving southward, covering farms and grazing lands. Part of the cause of desertification in the Sahel has been land degradation and removal of trees and shrubs that held back the sand. To remedy this situation, a wall of trees some 4500 miles long is envisaged, and production of seedlings by communities is well under way. The idea for the Initiative (GGWSSI), was launched in 2007 by the African Union (AU) and plans to reverse the effects of land degradation and desertification. The model for this giant vegetation planting scheme, is the Chinese Great Green Wall, being planted over a vast area. The Great Green Wall is an African-led movement to grow an 8 000km line of trees across the entire width of Africa to fight climate change, drought, famine, conflict, and migration.
- Food and Trees for Africa, a South African NGO, has distributed 4.2 million trees over the years, and set up a variety of community tree nurseries in townships around South Africa
The idea is to consider mass tree planting and catchment/flood plain restoration as a key disaster prevention activity, along with other measures like the building of canals, or re-planning the locality of towns and cities, moving them (difficult!) to higher ground.
Sources of information