China experienced record-setting floods this summer, disrupting the daily lives of millions. The Pearl River Delta and Greater Bay Area are also at higher risk of extreme weather events, as higher temperatures and sea-level rise increase the frequency and impact of extreme storms, threatening infrastructure and people’s homes, water safety, agriculture and energy supply. This seriously threatens the livelihoods of Hongkongers and others in the region.
For example, in 2017, Typhoon Hato, one of the strongest typhoons in this region in the past 50 years, caused significant damage totalling US$6.82 billion along its path. Mangkhut was another intense and destructive typhoon in 2018.
Building and restoring “natural infrastructure” – mangrove forests, salt marshes, oyster reefs and other coastal wetland ecosystems that protect shorelines -is a cost-effective approach to mitigating threats. By doing so, we can also enhance biodiversity, revive fish populations and improve water quality.
Get the latest insights and analysis from our Global Impact newsletter on the big stories originating in China.
The physical structure of coastal natural infrastructure absorbs wave energy and decreases erosion, while also protecting shorelines and the buildings along coastlines from the effects of waves and erosion due to rising sea levels. According to a new report published by The Nature Conservancy, the United Nations Development Programme and other partners, if today’s mangroves were lost around the world, 18 million more people would be affected by flooding every year (a 39 per cent increase) and annual property damage would increase by 16 per cent.
Some of these impacts can already be seen in the Greater Bay Area. Oyster reefs in Deep Bay in Hong Kong, once restored at scale, could serve as a buffer like mangroves to reduce wave energy that erodes shorelines; their natural growth provides added benefits, such as habitat creation and water filtration.
Natural infrastructure can perform better and at lower cost than man-made “grey infrastructure” such as levees and dams. Traditional artificial breakwaters may sink over time, losing their defensive function and requiring higher maintenance costs, whereas coastal habitats have the ability for self-repair and growth with sea-level rise.
They also protect property and assets from losses due to natural disasters. In China, mangroves protect 800,000 people from flooding and US$19 billion of property from flood damage. Forests and mangroves can reduce economic losses and overall risk from floods and droughts, which caused US$1.5 trillion in damage worldwide between 2003 and 2013, and are expected to dramatically worsen with climate change.
Large-scale ecosystem restoration efforts supported by government programmes have enormous potential to create jobs – perhaps as many as 40 jobs for every US$1 million invested, according to the same report.
Natural infrastructure is and should be playing an increasing role in mitigating risks of climate change and enhancing community climate resilience and adaptability. That is not to suggest that natural infrastructure should replace artificial or grey infrastructure. A blend of natural and artificial infrastructure should be promoted.
Lulu Zhou, director of strategic partnerships, The Nature Conservancy – Asia-Pacific
More Articles from SCMP
This article originally appeared on the South China Morning Post (www.scmp.com), the leading news media reporting on China and Asia.
Copyright (c) 2020. South China Morning Post Publishers Ltd. All rights reserved.