New biodiversity framework estimates what landscapes could support, not just what lives there

New biodiversity framework estimates what landscapes could support, not just what lives there Sadie Harley Scientific Editor Robert Egan Senior Editor A flower strip is established along the edge of a field. A wetland is restored. More seminatural habitats are created. The expectation is simple: give nature more space, and biodiversity will increase. But reality is often not so simple. Across Europe, researchers and policymakers have repeatedly observed the same puzzling pattern. Measures designed to benefit biodiversity can produce impressive results in one landscape while having only limited effects in another. Sometimes, the same intervention can even lead to contrasting outcomes depending on where it is implemented. For years, researchers have documented this inconsistency, but explaining it has been far more difficult. Now a team of researchers from the Department of Agroecology at Aarhus University, led by professor Christopher John Topping, believes it may have found part of the answer. In a paper published in npj Sustainable Agriculture, the researchers introduce a concept called Functional Trait Capacity, or FTC for short. Rather than focusing solely on the biodiversity observed today, FTC estimates the range of life strategies that a landscape can support under specific environmental and management conditions. The paper, "Functional Trait Capacity: from observing biodiversity to predicting landscape capacity" is written by Christopher John Topping, Tommy Dalgaard, Claus Rasmussen and Yoko Luise Dupont. The idea may sound technical, but its implications are straightforward: a landscape can hold far more ecological potential than current biodiversity surveys reveal. Looking beyond what we can see Most biodiversity indicators are based on observation. Researchers count species, assess habitats or examine the functional traits of plants and animals already present in a landscape. These approaches have become increasingly sophisticated and remain essential for understanding the state of nature. Yet researchers argue that all these methods share a common limitation. They tell us what biodiversity exists today, but they are less suited to answering forward-looking questions such as: What biodiversity could this landscape support in the future? "Current biodiversity metrics are very good at telling us what is there. But they are much less able to tell us what could be there," says Topping. "If we want to make informed decisions about biodiversity restoration, we also need to understand the potential capacity of a landscape." The new FTC framework seeks to fill that gap. Instead of measuring the species already present, it estimates how many different forms of life a landscape could potentially support under a given set of environmental and management conditions. In other words, it attempts to reveal the landscape's hidden ecological potential. The concept builds on the idea that biodiversity is shaped by access to resources, habitat structure, disturbance patterns and ecological interactions. Species come and go, but the underlying capacity of a landscape can determine what kinds of life are actually able to survive there over time. The biodiversity you do not see To demonstrate the idea, the researchers from Aarhus University developed a computational experiment involving four agricultural landscapes. At first glance, the landscapes appeared remarkably similar. Each contained exactly the same observed biodiversity community. Using conventional biodiversity measurements, they would therefore look almost identical. But when the team calculated Functional Trait Capacity, the similarities disappeared. The surprising finding was that seemingly similar landscapes could have very different biodiversity potential. While traditional surveys suggested the landscapes were the same, the new analysis revealed that some could support far more biodiversity than others. In other words, two landscapes may look equally rich in nature today, while one has much greater potential to host a wider variety of plants and animals in the future. That hidden potential is exactly what the researchers are trying to measure with Functional Trait Capacity. "That was one of the most striking results," says Topping. "Two landscapes can look very similar when we measure what is currently present, yet they may have very different abilities to support biodiversity in the future." The finding suggests that current biodiversity assessments may sometimes overlook important differences between landscapes, particularly when planning restoration efforts. Why the same measure produces different results The researchers then tested what happened when exactly the same conservation measure was applied across all four landscapes. In each case, 5% of cropped land was converted into seminatural herbaceous habitat. The intervention was implemented in the same way everywhere. If biodiversity outcomes depended only on the measure itself, the results should have been broadly similar. They were not. In one landscape, the intervention opened up 14 new opportunities for biodiversity. In another, it created only four. In two landscapes, the intervention produced no increase in capacity at all. The difference was not the intervention. The difference was the landscape. According to the researchers, this helps explain why biodiversity measures often generate highly variable outcomes in practice. "The effectiveness of an intervention depends on what limits biodiversity in the first place," says Topping. "The same action can unlock new ecological opportunities in one landscape while having very little effect in another because different constraints are operating." The study's computational demonstration illustrates how landscape context influences biodiversity capacity and management outcomes. The result aligns with a growing body of research showing that biodiversity responses depend heavily on landscape structure, habitat availability and surrounding land use. Supporting better decisions The researchers emphasize that FTC is not intended to replace existing biodiversity monitoring programs. Monitoring remains essential because it tells us what species and habitats are present and how they change over time. FTC serves a different role. It estimates what a landscape could support under alternative management regimes. This distinction could become increasingly important as governments, businesses and land managers seek to meet biodiversity targets under initiatives such as the Kunming-Montreal Global Biodiversity Framework and the EU Nature Restoration Regulation. Many current biodiversity indicators are designed to measure progress. FTC is designed to help guide decisions. Where are restoration efforts most likely to succeed? Which landscapes have the greatest capacity to respond? Which ecological constraints should be addressed first? These are the types of questions the researchers ultimately hope the framework can help answer. "If society wants to invest wisely in biodiversity restoration, we need tools that can help anticipate outcomes before actions are taken," says Topping. "FTC is an attempt to move from simply observing biodiversity toward understanding what landscapes are actually capable of supporting." There is another reason why the researchers believe new approaches may be needed. In practice, many biodiversity policies are not based on direct measurements of species populations. Instead, they rely on habitat indicators that can be mapped and monitored across large areas. Under many existing schemes, habitat area, habitat quality or landscape features are measured and then used to infer the expected benefits for biodiversity. This approach is practical because habitats can be mapped efficiently, whereas counting species across entire countries is often impossible. "The challenge is that we often assume that better habitat automatically translates into better outcomes for biodiversity," says Topping. "That assumption is reasonable, but it is not always tested. For plants the relationship can be quite strong, but for many animals and insects it can be much weaker." According to the researchers, this helps explain why measures that appear beneficial on paper do not always deliver the biodiversity outcomes that policymakers hope for. FTC seeks to address this challenge by focusing on the ecological processes and conditions that determine whether different forms of life can persist in a landscape. A proof of concept with ambitious goals The researchers are careful not to overstate their results. The study is a proof of concept demonstrating that Functional Trait Capacity can be calculated. It does not yet prove that FTC predicts real-world biodiversity outcomes. The next step will be to test the framework against empirical observations and data from actual landscapes. Even so, the concept introduces a fundamentally new way of thinking about biodiversity assessment. For decades, biodiversity research has focused on measuring what exists. FTC asks a different question: what is possible? More information Christopher John Topping et al., Functional Trait Capacity: from observing biodiversity to predicting landscape capacity, npj Sustainable Agriculture (2026). DOI: 10.1038/s44264-026-00190-5 Provided by Aarhus University