Recently, a global assessment done by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) ─ an independent body established by UN member States in 2012 to strengthen the science-policy interface for biodiversity and ecosystem services ─ highlighted a knowledge gap: understanding where and how nature’s contributions are more relevant to people.
The assessment, released earlier this year, was quite clear: ‘Nature and its vital contributions to people, which together embody biodiversity and ecosystem functions and services, are deteriorating worldwide’. More than 75 per cent of our planet’s land area and 66 per cent of oceans have been severely altered by human activity.
Now a new modelling study published in Science, ‘Global modeling of nature’s contributions to people’, has found that where people’s needs for nature are now greatest, nature’s ability to meet those needs is declining. Some 5 billion people could face food and water scarcity over the next 30 years as a result of that decline. Moreover, hundreds of millions could have a higher risk of coastal hazards such as shoreline erosion and flooding.
Lead author Rebecca Chaplin-Kramer, from Stanford University, said ‘I hope no one is shocked that billions of people could be impacted by 2050’, ‘We know we are dependent on nature for many things’, informs National Geographic.
The IPBES assessment defines nature’s contributions as all the benefits that humanity obtains from nature; it includes ecosystem goods and services. The model considered three of these: water quality, coastal protection, and crop pollination. Modelling results show that globally, up to 4.5 billion people face higher water pollution, and 5 billion may experience local losses in crop production due to insufficient pollination. Coastal risk increases everywhere in the globe under sea-level rise scenarios. Unsurprisingly, people in developing countries, particularly in Africa and South Asia, would be the hardest hit by future impacts, since they are more directly dependent on nature, whereas developed countries can buffer impacts, for example, through food imports.
The model examined different future standard scenarios regarding land use, climate and population change until 2050, put forward by Carbon Brief. Although the decline of nature is quite clear, its impacts are not so clear, and this new model makes them more visible, showing the number of people affected and where in Earth. According to Patrician Balvanera, from the Universidad Nacional Autónoma de México, author of an accompanying article in Science, the magnitude of those impacts won’t be mitigated by technology or infrastructure. While South Asia would need thousands of water treatment plants to provide clean water, nature can do it for free. Similarly, restoring coastal mangrove and seagrass ecosystems would protect Madagascar’s coasts rather than expensive seawalls.
According to the IPBES assessment, nature can be conserved, restored and used sustainably while other global goals are simultaneously met through urgent and concerted efforts fostering transformative change. It calls for structural change: new frameworks for private sector investment and innovation, inclusive and adaptive governance approaches and arrangements, multi-sectoral planning, and strategic policy mixes can help to transform the public and private sectors to achieve sustainability at the local, national and global levels.
The model is available online for anyone to examine the impacts of policy decisions.