COP17: ‘Biodiversity is our first line of defence against climate change’

For scientists, conferences where world leaders discuss biodiversity (COP17) and climate (COP31) are events they eagerly look forward to. They hope to see their findings translated there into binding agreements for all countries. Official reports from the UN working groups IPCC (climate) and IPBES (biodiversity) have long shown that climate change and biodiversity loss go hand in hand and reinforce one another. The effects reinforce each other through complex, self-reinforcing cycles.

Jeanne Nel, Liesje Mommer and Tim van Hattum, all researchers at Wageningen University & Research, aim to spread this message far and wide during the biodiversity summit in Yerevan and the climate summit in Antalya. Whilst each works on their own aspect of the issue, they share the conviction that the climate crisis and the biodiversity crisis cannot be viewed in isolation from one another. Tim van Hattum heads the Wageningen programme Green Climate Solutions, which develops green solutions to tackle climate change. In his view, nature is the first line of defence against climate change: ‘The natural system absorbs half of the total CO2 emitted worldwide. Furthermore, nature makes us more resilient to the effects of climate change, from floods and droughts to heatwaves. Nature is the greatest climate solution, yet unfortunately it is hardly ever utilised as such. Most attention and funding go to technological solutions, such as the energy transition and electric cars. These are important too, but we are overlooking the most obvious solution: investing more in nature.’

Conversely, climate change is accelerating the extinction of animal and plant species. Liesje Mommer, Professor of Belowground Ecology, is the driving force behind the Wageningen Biodiversity Initiative, which is committed to restoring biodiversity across the landscape. Among other things, Mommer has demonstrated that species-rich plant communities thrive better than monocultures of those same species. Moreover, mixed plant communities are more disease-resilient. Part of the explanation lies underground, in the complex networks of fungi and bacteria surrounding plant roots.  

These findings stand in stark contrast to the downward spiral into which, according to Mommer, the world has fallen. ‘Deforestation disrupts the nutrient cycle and the water cycle. Trees grow less well and store less CO2 in their wood. And fewer sugars end up in the soil, where they are fixed by bacteria and fungi. When entire forests are clear-cut, you not only lose all the organisms living there, but the buffering capacity of natural landscapes also disappears. This makes it even warmer and drier, and you end up in a spiral where the negative effects reinforce one another.’ 

The pace at which nature and the climate are breaking down is a cause for concern, says Jeanne Nel, head of the Biodiverse Environment programme at Wageningen University & Research. ‘The scientific consensus on climate change is now that we have misjudged the pace: it is happening even faster than scientists thought. For ten thousand years, the Earth’s climate was reasonably stable. We have now entered a phase of climate unpredictability. This summer’s drought was already unprecedented. The new reality, however, is that this is still the most stable period we will ever experience.’ 

Limiting overshoot,  the recent report by UNEP, the United Nations Environment Programme, confirms this alarming picture. It says the world is likely to exceed the ‘Paris 1.5-degree target’ within a few years. The only viable strategy left to the world is to limit the overshoot. Van Hattum has been making frequent use of a graph from the report recently to emphasise his message: ‘We must keep the time the world spends above that threshold as short as possible and bring the curve down over the coming decades. This should be the top priority for all politicians, all governments and all CEOs around the world.’

In 2021, the IPCC and IPBES published a joint report calling for a unified approach to climate and biodiversity, including their social implications. Five years on, that message is still barely reflected in policy. And according to Mommer, this could have undesirable effects: ‘Climate measures can seriously hamper biodiversity, for example when natural habitats have to make way for wind farms and solar parks. Conversely, the vast majority of biodiversity solutions are also good for the climate.’ 

She laments the compartmentalised thinking: ‘There’s a CO2 problem, a water problem, a drought problem, a problem with wildfires. Solutions to individual problems are not enough.’ Nel adds: ‘These are systemic challenges: a whole series of crises that share the same roots. I call it a polycrisis: biodiversity, climate change and poverty are all caused by the same systemic failures. That is also a source of hope, because if you tackle that polycrisis at its roots, you tackle all the individual crises.’  

But time is running out. Van Hattum: ‘The latest IPCC report states that the choices we make over the coming decade will have consequences for thousands of years to come. That places a heavy responsibility on everyone living today, including us as scientists. Our traditional role – gathering facts and providing a knowledge base – is no longer enough. We must take a much more proactive role, get involved in citizens’ initiatives and inspire others to find paths towards the future.’

And that is a new role, as Mommer also acknowledges: ‘Scientists have studied the problem as outsiders for far too long. We have always been observers. Now we must participate more actively if we want to help tackle these challenges. As a patient, a doctor who merely says, “You have a serious illness,” is of no use to you. You want a doctor who also says, “These are the treatment options, and this is my advice.” Let’s stop debating the need for integrated biodiversity and climate policy. The fact is that we are heading for disaster unless we act now. It helps enormously if we can, together, show the scientific consensus and the uncertainties and interdependencies. The IPCC and IPBES demonstrate how to arrive at rigorous scientific knowledge: by systematically reviewing large volumes of research and explicitly taking uncertainties into account.’

The reality is that forty years of sounding the alarm has led to too little action. According to Van Hattum, we need a message of hope about where we need to go and how we get there. With his map of the Netherlands in 2120, he laid out his vision for how the Netherlands could be climate-resilient in a century if nature were given more space. What happened next was encouraging: ‘That map turned up everywhere, from school classes to the House of Representatives. Even the European Commission was talking about it. The vision of the future sparked a whole movement of people keen to get involved. It helps to show what the world will look like if we do the right things. And then comes the hard work: making the right decisions now.’ 

Where do the scientists see opportunities? One pillar stands out: food. Van Hattum: ‘The global food system accounts for 70 percent of biodiversity loss and 30 percent of greenhouse gas emissions. Changing the food system is therefore essential to a sustainable future, globally and here. The challenge is not: how do we reduce emissions, but: how can we produce sufficient healthy food within planetary boundaries and in a changing climate?’  

Local communities are crucial to this approach: we must work together to find solutions. In an earlier article, Wageningen scientists highlight the growing recognition of the role that indigenous communities play worldwide in nature conservation and restoration. Nel sees positive initiatives in this area all over the world. For example, the Horizon Europe project TRANSPATH is working with small-scale Ghanaian farmers to develop cocoa production that benefits biodiversity and does not lead to deforestation. Closer to home, she praises initiatives such as the Dutch Collectief Natuurinclusief, which brings together public and private sector organisations to ensure that nature is fully integrated into social, economic and spatial decisions. She also describes Herenboeren and Land van Ons as highly promising – Dutch citizen cooperatives for sustainable food production that are shifting agricultural land away from monoculture.

The question that preoccupies her is how such positive initiatives can become the norm. ‘How do you steer networks of change in a targeted way; how do you weave networks between citizens and policymakers? And where are the obstacles? If you know which parties are perpetuating existing systems and what their narrative is, then we can also better determine how to win over the “well-meaning middle.”’ 

He says the message of hope is that the solutions to the climate crisis already exist. ‘And nature is the easiest solution we have. What’s more, it is much cheaper to tackle the climate crisis now than not to. The solutions are there, the money is there; we just need to get started. And yes, a lot of good work is already being done, but we really need to step up the pace. I hope that sense of urgency comes across at COP17 and COP31.’

Although the three believe there should really be a single summit for both climate and biodiversity, the reality is that there are two separate forums. Nel: ‘But important discussions are taking place, and these are the only processes we have to arrive at global solutions. Let’s cherish that. In addition, we are the Dutch ambassadors who, in the meantime, must try to mobilise as many people as possible bottom-up. That way, together we can create the momentum for change.’ 

Mommer also recognises that pushback works. She cites the example of the courageous Austrian minister, Ms Gewessler, who voted in favour of the European Nature Restoration Law against the wishes of her own cabinet: ‘Although scientists were overwhelmingly in favour of that law, it would not have come into being without the signature of that one courageous woman. Something similar happened in 2022 during the COP15 on biodiversity in Montreal. The conference was already two days over time and everyone was exhausted. Until an Indigenous delegate from Mexico stood up and said that an agreement would be the best birthday present for her niece. That’s when they finally reached a deal. Breakthroughs also require courage and persistence.'

One such breakthrough is the introduction of the European Soil Monitoring Directive, which aims to restore all soils in Europe to a healthy state by 2050. Her Wageningen Biodiversity Initiative helped provide the scientific basis for this directive, on which more than thirty European research institutions collaborated. Further encouraging policy developments are underway. For instance, the previous government decided that water and soil must be the guiding principles for all spatial planning decisions in the Netherlands. Van Hattum: ‘That is a truly promising policy, because it means the State is saying that a healthy natural system is crucial to the future of the Netherlands. And in September, Delta Programme Commissioner Co Verdaas said that the Netherlands needs to invest twice as much in water management as it does now. He argued that this can no longer be done in the traditional, technical way. We need to take a much more nature-based approach.’