Protecting biodiversity is often justified by the idea that more diverse ecosystems work better. A major new global synthesis suggests that this principle extends across a much wider range of benefits to people than previous evidence could show, while also revealing that some ecosystem services are far more sensitive to biodiversity loss than others.
Researchers writing in Nature Ecology & Evolution assembled evidence from 423 studies linking biodiversity with ecosystem functions and services, creating what they describe as the largest global database of its kind. Across 23 categories, higher biodiversity generally supported stronger ecosystem functioning and service delivery, including carbon capture, food production, pollination and water quality.
The strongest signal appeared in oceanic carbon sequestration. Its standardized biodiversity effect size reached Fisher’s z = 1.48, substantially larger than the effects estimated for most other services. But that striking result came with an important warning: the marine carbon estimate was based on only seven datasets, compared with 154 for terrestrial carbon sequestration.
The study therefore strengthens the case that biodiversity is functional infrastructure, not simply a count of species. At the same time, it shows why conservation cannot rely on a single rule about how many species an ecosystem can afford to lose.
A database more than twice the size of the previous benchmark
The research team began with a broad literature search for studies explicitly linking biodiversity to ecosystem services or ecosystem functions. Their search identified more than 312,000 publications. A stratified screening process narrowed the literature to studies containing suitable quantitative relationships.
The final database contained 423 studies and thousands of individual biodiversity-function observations across terrestrial, freshwater, marine and estuarine systems. The authors report that this collection is more than twice as large as the next-largest comparable database.
Coverage was still uneven. Terrestrial ecosystems contributed 1,759 datasets, compared with 183 freshwater, 153 marine and just 23 estuarine datasets. There were also 1,079 observational datasets and 879 experimental datasets in the database.
The geographic distribution was similarly uneven, with research concentrated in developed countries. That matters because the places most dependent on local ecosystem services are not necessarily the places where those relationships have been studied most intensively.
Linear relationships were almost as common as saturating ones
One of the study’s central questions concerned the shape of the relationship between biodiversity and ecosystem performance.
A saturating relationship would imply that benefits rise quickly as diversity increases but eventually level off. In such a system, some species may perform overlapping ecological roles, creating a degree of functional redundancy. A linear relationship implies that ecosystem performance continues to rise across the observed biodiversity range, suggesting that additional species keep contributing rather than rapidly becoming interchangeable.
Across the 23 ecosystem service and function categories, the researchers found that 11 were best described by quadratic relationships, 10 by linear relationships and only two by logarithmic relationships. When the models were simplified into linear versus saturating forms, 46% supported a linear relationship and 54% a saturating one.
That near-even split challenges the idea that ecosystem functions typically reach a plateau at relatively modest levels of diversity. The authors argue that functional redundancy may often be overestimated because many empirical studies have not sampled biodiversity levels high enough to observe where true saturation occurs.
Regulating services such as water quality and pollination were commonly linear. In those cases, biodiversity loss could continue reducing service delivery even before a dramatic ecological threshold is crossed.
Biodiversity improved most functions and services
The researchers next converted the varied relationships into a standardized effect-size framework so that different services could be compared on a common basis.
Higher biodiversity enhanced most of the ecosystem services and functions examined. The magnitude varied widely. Air-quality regulation, for example, had a very weak estimated effect of around Fisher’s z = -0.03, while oceanic carbon sequestration reached 1.48.
Carbon sequestration, biomass turnover and food and feed provision were among the functions showing particularly strong sensitivity to biodiversity. The results reinforce the idea that biodiversity loss can affect processes directly relevant to climate mitigation and food systems rather than only changing the composition of ecological communities.
However, most individual biodiversity-ecosystem relationships had relatively modest explanatory power, often with r² values below 0.4. Biodiversity therefore matters, but it operates alongside climate, habitat, species identity, environmental conditions and many other factors.
Marine carbon showed the strongest biodiversity signal
The standout result was the unusually large effect estimated for oceanic carbon sequestration.
Marine ecosystems play a major role in the global carbon cycle. Biological communities influence how carbon is captured, transferred through food webs and eventually stored. The synthesis suggests that this service may be particularly dependent on maintaining diverse communities.
That gives marine conservation a potential climate dimension beyond protecting individual threatened species. If biodiversity contributes strongly to carbon sequestration, preserving ecological diversity may help protect the processes on which blue-carbon strategies depend.
But the evidence base is still thin. Only seven datasets contributed to the oceanic carbon effect estimate. A large effect derived from a small literature can be scientifically important without being precise enough to support sweeping quantitative predictions.
The authors therefore identify marine biodiversity-function research as a major evidence gap. The finding is a reason for more investigation, not a licence to assume that every additional marine species produces the same carbon benefit.
Some services depend more on particular species than total diversity
Not every ecosystem service responded strongly to biodiversity as a whole.
Hazard regulation showed weak overall sensitivity in the standardized effect-size analysis, with an effect near zero and an r² of 0.17. This does not mean biodiversity is irrelevant to protection from hazards.
Instead, some services may depend disproportionately on a small number of functionally distinctive species or ecosystem engineers. Mangroves, reef-building corals, large trees or other foundational organisms can shape entire habitats in ways that are not easily replaced by simply adding more species.
This distinction creates two different conservation problems. In some ecosystems, preserving broad diversity may protect a service because many species contribute incrementally. In others, losing one functionally irreplaceable species could matter more than a change in total species richness.
The study argues that conservation planning needs to recognise both forms of dependence.
Scale changed how strongly biodiversity mattered
The relationship between biodiversity and ecosystem performance also depended on the spatial scale at which researchers measured it.
Across the full dataset, biodiversity effects became stronger as spatial grain increased, with a reported coefficient of β = 210.26, P < 0.001. The exact pattern varied by service, but the general result suggests that biodiversity’s contribution can become more visible across larger areas.
One possible explanation is beta diversity, the change in species composition from one location to another. Two sites may each contain a modest number of species while collectively supporting a much broader range of ecological roles. Looking only at a small plot can therefore miss the insurance and complementarity provided by variation across landscapes.
This is another reason not to interpret biodiversity-function relationships as universal fixed equations. Experimental design, habitat and spatial scale all changed the observed effects.
The researchers used the synthesis to look ahead
The study did not stop at describing past experiments. The researchers combined their biodiversity-service relationships with projected changes in the Biodiversity Intactness Index under different Shared Socioeconomic Pathways.
They used this framework to explore future biological pest regulation, an ecosystem service with direct relevance to food production.
Under a fossil-fuelled development pathway, the model projected weaker natural-enemy-to-pest ratios in North America, South America and Asia relative to a middle-of-the-road scenario. Countries with lower Human Development Index values were also predicted to have lower pest-protection potential, with a reported relationship of β = 0.176 ± 0.038, z = 4.59, P = 4.41 × 10-6.
The fossil-fuel development scenario further worsened this association, with β = -0.049 ± 0.011, z = -4.60, P = 4.27 × 10-6.
These forecasts are not direct observations of the future. They depend on biodiversity projections, the relationships estimated from existing studies and assumptions about how those relationships transfer across space and time. The authors explicitly note that their biodiversity projections do not identify which species are lost, even though species identity can matter greatly for ecosystem function.
Why the findings matter beyond conservation
The study reframes biodiversity as a contributor to systems people routinely depend on.
Pollination affects crop production. Biological pest control can reduce pressure on agriculture. Water purification influences water quality. Carbon sequestration shapes climate regulation. Food and feed production are themselves ecosystem services.
If biodiversity supports these processes, species loss can create economic and social consequences even before an ecosystem visibly collapses.
This perspective complements recent Research Today coverage of urban greening and heat inequality. Both studies show that environmental conditions can translate into measurable benefits for people, although the biodiversity synthesis operates across a far broader range of ecosystems and services.
The global evidence still has important blind spots
The scale of the synthesis is a strength, but it also exposes the limitations of the evidence base it combines.
Terrestrial studies dominate the literature, while marine, freshwater and especially estuarine ecosystems are less represented. Research sites are concentrated in developed countries. Some ecosystem-service categories contain many observations while others rely on small samples.
The underlying studies also differ in experimental design, biodiversity measures, spatial scale and the way ecosystem services are quantified. Those differences contribute to the relatively low or moderate explanatory power seen in many categories.
Meta-analytic relationships are also not proof that adding species to any particular ecosystem will automatically produce the average benefit reported across the database. Biodiversity can be both a cause and a consequence of favourable environmental conditions, particularly in observational research.
Finally, the future projections treat changes in biodiversity intactness in aggregate. Real biodiversity loss is selective. If the species most likely to disappear are unusually important for a particular function, the consequences could be larger than an aggregate model predicts. If lost species are functionally redundant, the effect could be smaller.
Biodiversity is not interchangeable
The strongest conclusion from the synthesis is not that every species contributes equally to every ecosystem service.
It is that biodiversity supports a surprisingly broad range of functions and services, and that the shape of those relationships varies enough to make simplistic assumptions dangerous.
Some services continue increasing across observed biodiversity gradients. Others saturate. Some appear highly sensitive to total diversity, while others depend on a few foundational species. Marine carbon sequestration may be exceptionally biodiversity-sensitive, but the evidence supporting that result remains comparatively sparse.
Conservation decisions therefore need to ask more than how many species remain. They need to consider which ecological functions are at stake, which organisms provide them, how those relationships change across space and how much uncertainty remains.
The new global synthesis makes one point difficult to ignore: losing biodiversity is not only about losing nature. It can also mean weakening the ecological machinery that delivers benefits people rely on.
Source Information
Study: Moffett, E. R., Gayford, J. H., Chen, L. et al. “Biodiversity safeguards ecosystem services and functions worldwide.”
Journal: Nature Ecology & Evolution.
Published: 6 October 2026.
DOI: 10.1038/s41559-026-03200-4
Study design: Global synthesis and meta-analysis of 423 studies linking biodiversity with ecosystem services and ecosystem functions across terrestrial, freshwater, marine and estuarine systems, followed by scenario-based forecasting of biodiversity-mediated ecosystem-service change.
