Plant diversity benefits conservation and agriculture: A global study reveals the effects of biodiversity

An international data analysis, in which the Leibniz Institute for the Analysis of Biodiversity Change (LIB) played a key role, shows that plant diversity enhances natural pest control in arable landscapes and stabilises ecosystems in meadows and forests. It therefore leads to higher yields in agriculture and forestry.

Plant diversity has long been regarded as key to stable and resilient ecosystems. However, until now, little was understood about why it has different effects in agricultural areas than in meadows or forests. An international research group, in which the Leibniz Institute for Biodiversity Change Analysis (LIB) played a key role, has now investigated this question for the first time on a global scale. The most comprehensive synthesis of data on this topic to date, entitled “Plant diversity modifies multi-trophic interactions in croplands, grasslands and forests”, shows that a greater number of plant species alter food webs in different ways depending on the ecosystem – with direct consequences for biodiversity, but also for the economy. The study is based on 149 field studies with data from 214 sites in 27 countries across five continents and was published in the journal Science Advances .

The study focused on the question of how plant diversity influences the interactions between plants, herbivorous insects and their natural predators. Whilst earlier studies looked at individual ecosystems or regions, the new analysis combines data from agricultural landscapes, grasslands and forests worldwide for the first time and shows that the underlying ecological mechanisms differ fundamentally.

“For the first time, we have been able to demonstrate on a global scale that plant diversity does not operate according to the same rules everywhere,” says Prof. Dr Christoph Scherber, Head of the Centre for Biodiversity Monitoring at the LIB and senior author of the study. “In agricultural systems, it primarily strengthens the natural predators of pests. In species-rich meadows and forests, by contrast, it initially leads to more herbivores and only subsequently to more predators. This knowledge helps us to understand how biodiversity stabilises ecosystems – and how we can make targeted use of it for sustainable agriculture.”

Species-rich fields promote natural pest control

The benefits of greater plant diversity are particularly evident in agricultural landscapes. There, predatory insects and parasitoids benefit more from greater plant diversity than herbivorous insect pests. This shifts the balance in favour of natural enemies – a pattern known as top-down control.

The analysis shows that the greater the plant diversity, the more beneficial insects there are. In organic farming, their ratio to herbivorous insects increases almost tenfold, whilst in conventional arable farming it rises by about one and a half times. At the same time, the abundance of herbivorous insects declined significantly. The findings suggest that more diverse cropping systems promote natural pest control and can thus make an important contribution to more sustainable agriculture.

“Our findings impressively demonstrate that biodiversity not only serves nature conservation but can also offer concrete benefits for agricultural production,” says Scherber. “Mixed cropping and diverse agricultural systems create better living conditions for beneficial insects and can help to limit pest infestations naturally. As a result, species-rich fields yield higher harvests than monocultures.”

Meadows and forests follow different rules

In grassland and forest ecosystems, however, the researchers observed a different pattern. There, greater plant diversity initially led to higher plant production and a greater food supply for herbivores. It was only these increasing populations that subsequently allowed for higher populations of their natural enemies. Biologists refer to this as a ‘bottom-up’ process.

The study thus demonstrates for the first time worldwide that the direction of trophic interactions – that is, food relationships – depends significantly on the ecosystem in question. Whilst natural pest control is the primary focus in agricultural landscapes, plant diversity in meadows and forests promotes the overall diversity of the food chain and thus helps to stabilise these ecosystems.

Confirmation of a groundbreaking LIB study

For the LIB, this publication is of particular scientific significance. It follows on directly from a paper by Christoph Scherber and colleagues published in the journal *Nature* in 2010. At that time, it was demonstrated experimentally for the first time that plant diversity has an impact on entire food chains. The new global data synthesis now confirms these relationships on the basis of field studies from a wide variety of regions around the world and expands upon them with a crucial finding: different ecological mechanisms dominate depending on the ecosystem.

The study was carried out in collaboration with more than 140 scientists from almost 40 different countries. Around 3,800 researchers were contacted between 2020 and 2025 to collect the data. Ultimately, data from 149 suitable field studies were consolidated. The analysis also incorporated data from the European research project DIVERSify, in which the LIB played a key role – including through the involvement of its then-staff members Silvia Pappagallo and Jana Brandmeier.

Biodiversity as the key to sustainable land use

The results underscore that biodiversity is far more than just a conservation goal. It influences key ecosystem services such as natural pest control, productivity and the stability of biological communities. Particularly in times of increasing climate extremes and growing demands for sustainable food production, these new findings provide an important scientific basis for designing resilient agricultural systems. The research suggests that mixed cropping should be favoured over monocultures.

Original publication

Plant diversity modifies multi-trophic interactions in croplands, grasslands and forests. Science Advances 12, 23 July 2026.

https://doi.org/10.1126/sciadv.aeb8680