He started his career as a part-time PhD candidate and a reading volunteer at his children's school. Now, as a professor, he looks back on forty years of research and education: Peter Klinkhamer of the Institute of Biology Leiden, ecologist in heart and soul.

It’s better to cut our nitrogen emissions now than to solve the consequences later at great expense. That’s the lesson we can learn from the Dutch nitrogen crisis, according to nitrogen expert Jan Willem Erisman. In Science, he shares this lesson with other countries. According to Erisman, we should…

Environmental economist Rutger Hoekstra is a guest researcher at Leiden University. He is studying the question of how we can measure societal progress based on a broader range of factors than only Gross Domestic Product.

Just like every other organism on Earth, plants’ ultimate goal is to survive and reproduce. In order to achieve this, they must make trade-offs between where and how to allocate their finite set of resources. Whether they put their resources and energy into their growth, reproduction or maintenance,…

Biodiversity and healthy ecosystems continue to decline in Europe, which has serious consequences for human welfare. These are findings of a report that was formally approved by delegates from 127 governments during a UN plenary in Medellin, Colombia. Leiden researcher Alexander van Oudenhoven was one…

If European countries rely solely on technological advances, they won't be able to limit global heating to 1.5 degrees. Households will also need to change their lifestyles. This 'inconvenient truth' is the result of calculations done by industrial ecologist Stephanie Cap. ‘It's not a popular message,…

When people and tigers use the same forest, their ability to cope and co-adapt to the influences of the other is much higher than currently understood. This is one of the conclusions drawn by Leiden BioSocial researcher Shekhar Kolipaka, who researched whether tigers can survive in human-dominated…

On 5 October, mediator Johan Remkes presented his report on the nitrogen crisis and what he thinks is the best way forward. Leiden University professor and nitrogen expert Jan Willem Erisman responds to Remkes’s recommendations. ‘It’s a step in the right direction.’

To what extent does human intervention influence the world’s biodiversity? And can we predict how biodiversity and ecosystems will change in the coming years? Inaugural lecture by Peter van Bodegom, Professor of Conservation Biology, on 8 May.

A tax on CO2 emissions from products entering the EU offers unprecedented opportunities in the fight against global warming. That is the conclusion of research on which Leiden environmental scientist Hauke Ward collaborated. ‘A new world is opening up,’ Ward says. ‘But success hinges on how we involve…

Fearing a trade-off with economic growth, countries feel discouraged to cut their CO2 emissions. But do the two really not go together? Environmental scientist Ranran Wang and her colleagues investigated the relationship between economic growth and CO2 emissions in 73 countries from 1970 to 2016. Wang:…

The Netherlands is embroiled in a complex nitrogen crisis. Berent Baris wants to use his NitroGenius game to demonstrate the complexity of this crisis.

When do we define a piece of nature in the city as a park? And when is something a tree or shrub? It may seem obvious, but in scientific literature the definitions vary quite a bit. That makes comparisons difficult. Environmental scientist Joeri Morpurgo looked at the differences and designed a general…

Around 1,300 Leideners found 2,265 species during the Expeditie Stadsnutuur urban biodiversity inventory. ‘It’s been a huge success’, says scientific coordinator Frederic Lens.

In his inaugural lecture Professor of Environmental Sustainability Jan Willem Erisman calls for local solutions that give people more freedom in how they meet environmental, nature and climate goals. This would allow farmers to come up with their own solutions to the nitrogen problem. The idea ties…

A valuable community of female researchers, providing solicited and unsolicited advice to the Board of the Faculty of Science. Those are the strengths of women’s network RISE. On 11 September the network presented its second biennial report.

Martina Vijver has been nominated as Teacher of the Year of the Faculty of Science. She gets this nomination for the course Ecotoxicology she taught in 2022. The 52 students who took the course were hugely enthusiastic, as can be read in their positive reviews. What is so great about this course then?…

Seven researchers from Leiden University have been awarded an ERC Starting Grant. This will enable them to start their own project, build their research team and put their best ideas into action.

Strengthening nature and at the same time investing in future-proof agriculture. That is the task of the Minister for Nature and Nitrogen, Christianne van der Wal. It is also the lifework of Leiden professor Jan Willem Erisman. He has been researching nitrogen for his entire career and has shown that…

What is the influence of the 2016 ban on free plastic bags on the environment? Industrial ecologist Stefano Cucurachi received a LUF grant of €75.000 to answer this question.

Hydropower plants need not be disastrous for fishermen and nature. For that, we need to place new dams more strategically, but also modify or even remove some existing ones. Valerio Barbarossa and Rafael Schmitt showed that with a computer model of the Asian Mekong basin.

The first of April was the official start of Phase II of the collaborative “PCAD4Cod”-project on the effect of sound on fish populations. Hans Slabbekoorn, associate professor at the IBL, is the principal investigator and collaborates with three PhD-students, Dr. Erwin Winter, (Wageningen Marine Research),…

It’s Circular Economy Week, from 1 to 6 February. But what is it that makes an economy circular? And just how circular is our university? René Kleijn, lecturer on the honours class Circular Economy: from challenge to opportunity, explains.

Cutting down global emissions of greenhouse gases to combat global warming won’t do the trick alone: we also need negative-emissions technology that can capture carbon dioxide directly out of the air. In the prestigious journal Global Environmental Change, PhD candidate Oscar Rueda and colleagues shed…

What we buy and consume in Europe often has an impact on biodiversity somewhere else in the world. With a Horizon Europe Funding of 600.000 euros, assistant professor Laura Scherer and her team will develop models to look at the impact of global trade in non-food biomass. ‘After developing the models,…

Although smartphones and other consumer cameras are increasingly used for scientific applications like citizen science, it’s still difficult to compare and combine data from different devices. PhD student Olivier Burggraaff developed a new easy-to-use standardised method which makes it possible for…

Fighting against cancer, antibiotic resistance and disposable plastics: Ahmed Ali, Fredj Ben Bdira, and Valerio Barbarossa receive a LUF grant for their innovative and socially relevant research. These grants for academic talent are often an important step towards grants by NWO and other grant insti…

Four students of the MSc Industrial Ecology have recently been selected to participate in the accelerator programme of the EIT Climate-KIC, which helps sustainable start-ups. The four students use coconut husks to develop sustainable boards, which can be used to make furniture.

How can the Dutch Sand Motor strengthen our coasts in a natural way? And how can this knowledge and experience help prevent coastal erosion in Jamaica? Researchers Alexander van Oudenhoven (Institute of Environmental Sciences Leiden) and Arjen Luijendijk (Delft University of Technology) have compiled…

According to a new study, for half of the world population the answer would be yes. For the other half: maybe? Leiden environmental researcher and head author Nicolas Navarre explains: ‘With improvements to crop yields, reductions in food waste, and changes in consumption patterns, 90% of people could…

Leiden University is in third place in the SustainaBul sustainability ranking. Students from eleven research universities and nine universities of applied sciences took part in the ranking.

Which plant species grow where - and why? In a new study in Nature Ecology & Evolution, an international research team presents the world's first global vegetation database which contains over 1.1 million complete lists of plant species for all terrestrial ecosystems. Leiden professor of Environmental…

Lions in Kenya respond very differently to human land use, climate and conservation practices. That is the conclusion of thesis from Leiden biologist Monica Chege. A uniform approach is therefore insufficient. ‘Effective conservation only works when management is tailored to local conditions and developed…

Your local city park may be improving your health, according to a new paper led by Leiden environmental scientist Roy Remme. In Proceedings of the National Academy of Sciences Remme and his colleagues describe how access to nature increases people’s physical activity—and therefore overall health—in…

What if we start taxing carbon-intensive products such as electricity and gasoline, and at the same time compensate low-income households? Hauke Ward and colleagues did just that in a computer simulation for Peru, with a remarkable outcome. Not only does the approach tackle climate change, but it could…

The changes that humans are making to the landscape are beneficial for mosquitoes that spread diseases such as Zika, chikungunya and dengue. This is what biologist Maarten Schrama and his colleagues write in the journal Nature Scientific Reports. ‘If we know in which living environments mosquitoes thrive…

While offshore wind farms generate clean and green energy, scientists are becoming increasingly aware of the harmful impact they may have on marine life. To get a better overview of these impacts and to find the best locations for future wind farms, environmental scientist Yali Si and her colleagues…

Not all sustainable business models have the impact they claim, Leiden researcher Levon Amatuni revealed. Car sharing and phone reuse, for example, have a smaller positive effect than previously thought. Amatuni advises people to ‘pay attention to actual changes in their consumption behaviour rather…

Anti-litter activist Dirk Groot photographed, tagged, and collected more than 400,000 pieces of litter in the Netherlands. Now, he and his data are included in a study on urban litter by researchers from Leiden University and Andrea Ballatore from Birkbeck, University of London.

The sand on European beaches may look pristine, but in every kilogram of sand there are on average 250 microplastics: fragments smaller than 5mm. These results are part of a study from Leiden researchers with the help of beach-goers throughout Europe.

You might take photos and selfies with your phone's camera, or scan a QR code. But there is much more you can do with it. Astronomer Olivier Burggraaff developed a phone attachment that allows you to take measurements of surface water with your smartphone. He will receive his PhD on 13 December.

Humans have influenced nature since as early as the Ice Age, and over the past century man’s impact has become even greater with our many new technologies and a growing world population. Leiden researchers study this impact and how we can keep it within reasonable limits so that nature can be preserved.…

She has had the idea for seven years, but now environmental scientist and conservation biologist Kat Stewart finally gets to work on it. She has been awarded a Vidi grant by NWO to find out how DNA from water can be used to shed light on invasive species and their impact on native populations.

Life cycle assessment (LCA) reveals the total environmental impact of products or production processes, and EU rules are going to make this even more important.

Hydrogen can help to solve the climate problem. At least, if we start producing it in the right, clean way. Leiden researchers mapped out the global environmental impact of hydrogen production and looked ahead to 2050. They published their work in Energy & Environmental Science.

With a single sample of water or soil, researches can analyse the DNA of everything that is living in that environment. During her research, PhD candidate Beilun Zhao discovered a way to analyse not only the kind of species, but also the age of the species in a water sample. The method showed its first…

The habitats of freshwater fish species are threatened by global warming, mainly due to rising water temperatures. This is the conclusion of a study led by Radboud University, in collaboration with Utrecht University, PBL Netherlands Environmental Assessment Agency, Leiden University and others. The…

Professor of Ecotoxicology Martina Vijver had planned an eight-week field work course for her students, but the corona virus threw a spanner in the works and Vijver had to come up with a new plan at short notice. ‘Without the help of my own network and that of my colleagues this would have been very…

You pour a scoop of ditch water in the DNA scanner, and voilà: you know exactly which plants and animals the ditch accommodates. Well, it is not that simple yet, but according to PhD candidate Kevin Beentjes, we can already use DNA techniques to monitor the quality of freshwater. For his PhD research,…

A more efficient solar panel sounds great. But what if these new panels consume more toxic materials, or their production consumes a lot of energy? Leiden environmental scientists, together with colleagues from the Fraunhofer ISE, address this multifaceted question in a new publication in the prestigious…