Small percentage of globe provides critical natural benefits to most of humanity
(Penn State University) - A small percentage of land and coastal waters provides most of the global population with the ecosystem services needed to support human well-being, and maintaining these areas can advance the United Nations’ development, climate and biodiversity conservation goals, according to an international team of researchers.
The researchers focused on 12 localscale and two global-scale types of ecosystem services that constitute nature’s contributions to people (NCP). These services have enormous cultural and economic value by providing food, drinking water, protection from hazards and many other benefits to humanity.
“Our comprehensive study demonstrates that a relatively small percent of the planet is disproportionately important to maintain and conserve,” said Larry Gorenflo, professor of landscape architecture, geography and African studies at Penn State. “There’s an additional 220,000 people on Earth every day, more or less. We’re extracting natural resources at a high volume and, in some cases, important ecosystem services that provide benefits such as clean water and air are being compromised more rapidly than they can be replenished through natural processes. This paper shows that some places in particular are really important to maintain for general human well-being.”
The researchers used satellite data to map all 14 NCP provided by terrestrial ecosystems and inland and marine waters across all continents except Antarctica. They attributed the magnitude of benefits and, where possible, the number of people benefiting from the services provided by ecosystems to each NCP. They re-sampled the data at a 1.25mile (2-kilometer) resolution and ran an optimization model to identify the minimum areas needed to reach target levels of every NCP. They ran the model within each country’s land borders and marine exclusive economic zone (EEZ) for the local NCP, and within all global land area and all countries’ EEZ for the global NCP.
The researchers found that conserving 30% of the Earth’s land and 24% of
coastal waters would sustain approximately 90% of nature’s current contributions to people in every country. They reported their findings in Nature Ecology and Evolution.
“All people on the planet benefit from nature,” said study lead author Becky Chaplin-Kramer, principal research scientist at the University of Minnesota. “What is striking is just how many benefit from a relatively modest proportion of our total global land area. If we can maintain these areas in their current state through a variety of conservation mechanisms that allow the types of use that make them so valuable, we can ensure that these benefits continue for years to come.”
Prioritizing conservation, protection and restoration efforts to areas identified as critical natural assets could efficiently maintain a high proportion of current natural benefits to people.
While only 16% of the global population live on lands containing these assets, the direct benefits of these critical natural areas are widespread – 6.1 billion people live within one hour’s travel and 3.7 billion people live downstream of the critical areas. Many more people may be impacted by the material benefits from nature that enter the global supply
chain.
Valuable ecosystems can be found in every corner of the planet, like the Congo Basin forests in Africa and the Appalachians in the U.S. Importantly, every country has some critical areas that benefit local communities, often found in headwaters of large river basins or near heavily populated areas. Areas that remain globally important for climate mitigation and biodiversity, like the Amazon, but cannot provide all critical local benefits may lead to additional conservation attention to nearby areas, like the Paraná River connecting the many population centers across central South America. Likewise, the headwaters of the Yangtze and Mekong rivers emerge as areas of key importance for many people in Asia.
“Here in the U.S., 37% of the land and 15% of our coastal waters provide 90% of critical benefits to local communities,” said Rachel Neugarten, study author and researcher at Cornell University. “If we work with local communities to conserve and sustainably manage these places, we could achieve climate and conservation goals while also securing the many benefits of nature for our children and grandchildren.”