Ecosystems most in need of intensive care can be identified using data from space through a simple test paving the way for potentially revolutionary approaches to protect and restore nature on a global scale.
Published in Current Biology, researchers from the Institute of Zoology at ZSL have unveiled an approach using satellite data to quickly diagnose an ecosystem’s health – like how a blood test can identify when a patient needs urgent treatment.
Tested with data from programmes using satellites to monitor forest across the United States, this new approach allows for rapid identification of the pockets of nature that need the most immediate attention, and gives conservationists and world leaders the data to prioritise action to restore the ecosystems that we all rely on.
Lead author Dr Jake Williams said, “Life across Earth is under pressure, with swathes of nature facing escalating threats such as habitat destruction and pollution. In the face of climate change and global biodiversity loss, urgent action is needed to protect our planet’s ecosystems. Understanding how these delicate systems are changing – and identifying those in the most critical condition – is vital to prioritising these efforts. Yet when we’re talking about something as complex and vast as life on Earth, the challenges of measuring these impacts and understanding where we need to be paying attention first are immense.
“Our work sets the stage for potential new, powerful tools that use patterns seen throughout nature to quickly and objectively identify which ecosystems need ‘medical’ intervention without reliance on subjective decisions about how these ecosystems should be. This could be a game changer for protecting life on Earth.”
How can we monitor ecosystems from space?
In a healthy ecosystem, there is a particular relationship between the total mass of organisms, such as trees and bushes, and their growth rate, number and diversity. Based on this, the authors used data from forest monitoring schemes across the US – both field data and information from NASA satellites measuring the light and radiation reflected by trees – to test the idea that the more deviation there is from that relationship, the unhealthier an ecosystem is.
In doing so, they showed that the difference between the predicted and actual mass of all trees was related to the conservation status of the ecosystem, suggesting its potential as a diagnostic measure of the health of an ecosystem.
Williams said, “Using US forests as a case study – from redwood forests in California to the oak forests of the Appalachian Mountains – we showed we can systematically measure ecosystems breaking down in the face of harmful human activities. In this case, we captured how the expected relationship between the number, diversity, productivity and mass of trees falls apart as human pressure increases – but the beauty of using this approach is it can be applied to patterns in any ecosystem.
“Identifying a way to methodically measure this change lays the foundation for revolutionary tools that could act like blood tests for nature – only instead of measuring how urgently someone with diabetes needs medical care, we’re looking at how pressingly an ecosystem needs conservation action. This idea was only predicted on paper before – now we’ve shown that it works in practice.”
How can this help?
International agreements – such as the Global Biodiversity Framework, which commits world leaders to halt and reverse nature loss – are essential to protecting nature and the pivotal role it plays in human existence. However, challenges with developing globally applicable measurable indicators mean there is a lack of policy-ready information that can galvanise political action and hold international actors accountable. A diagnostic test for ecosystems would help overcome these challenges, helping global decision makers and conservationists identify where best to invest their time and money, while easily measuring movement towards these commitments.
Professor Nathalie Pettorelli, co-author and fellow researcher at the Institute of Zoology said, “Healthy, functioning ecosystems underpin our wellbeing and quality of life. They give us food, clean air, fresh water, stable climates as well as protection from extreme events. Improving the health of our natural ecosystems is a proven, cost-effective way to address the current nature, health and climate crises. The quicker we can take action to protect and restore ecosystems, the sooner we can get our planet back on track.
“We have substantial knowledge and experience in nature recovery needed to safeguard a livable world for all. But we still face the challenge of lacking a standardised way to prioritise action – and monitor its impact – in a rapidly changing world. Our work addresses this issue, by strengthening the case for fundamental ecosystem laws and providing a measurable concept of ecosystem health that, most importantly, doesn’t rely on a reference state. This could have major implications, notably for assessing national and international progress towards our ecosystem-based biodiversity targets and for ensuring that the world remains on track to meet its commitments to restore the natural world we all depend on.”