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Leiden Mayor Lenferink gets his feet dirty for opening Polderlab Oud Ade

On Thursday 9 September, the mayor of Leiden officially launched a unique ten-year research project in the polder near Oud Ade. During a festive opening in the countryside, he and all the parties involved ceremoniously planted the first trees. Because one thing is certain: the traditional grass landscape is going to change.

It is bright and sunny when the delegates arrive at the green Vrouw Vennepolder in Oud Ade. Mayor Henri Lenferink of Leiden, President of the Executive Board of Leiden University Annetje Ottow and President Franke Remerie of Land van Ons will officially open the Polderlab. They have to roll up their sleeves: each of them receives a shovel and a tree to plant. For a moment, the mayor scratches his head about his neat shoes, but nevertheless fanatically sets to work.

Watch the video report of the opening

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This is what a future peat meadow looks like

'This is where the future of the peat meadow area begins,' says biologist Maarten Schrama of the Institute of Environmental Sciences Leiden. 'If we want to combat subsidence and the emission of CO2 and nitrogen, we have two options. Either we turn it into one big marshland. Or we can see if we can make it a usable and profitable landscape for farmers as well. Even if the sea level rises in the future. That’s the big question we’re trying to answer here.’

That new peat meadow area will no longer consist of grassland only. Schrama: ‘We are going to make the area wetter again and try out different cultivation methods and forms of agriculture. Think of sheep, plants that are resistant to a higher water level, such as cranberries and hedges to provide shelter for birds and insects.’

Getting dirty: The delegation plants several fruit trees as a start to the research in the Polderlab.

Mayor Lenferink: 'Bring back the Blaarkop'

Mayor Henri Lenferink is proud that Leiden and the surrounding municipalities are working together to find solutions to problems faced by several European coutries. ‘It is great to see that our city has such good cooperation with the university and other knowledge institutes. Plus I've noticed that the surrounding municipalities also feel strongly connected. That's why we decided to do this together. It is wonderful that so many parties are going to work hard to make this a success.

'We must adapt to the landscape and not the other way around.'

The mayor himself has already given some thought to the new landscape. ‘I say: bring back the Blaarkop. An old breed of cow that can stand high water and gives the best milk and butter.’ Not a bad idea according to Schrama: 'These old breeds are much better adapted to wet landscapes. Our current cows are giants with small legs, and sink into the ground everywhere. That is why we have to adjust the water level, which makes our peat subside. We have to adapt the cows to the existing landscape and not the other way round. So, the old cows could be a success.'

More knowledge about what we do

Land van Ons is happy to make its land available for this unique research, according to President Remerie: 'We actually know so little about biodiversity. And yet we take all sorts of measures and intervene in nature without knowing the consequences. We find this knowledge very important, also for our other plots. We hope that more Dutch people will participate and that together we can give biodiversity an enormous boost!'

More information about the background to this project can be read in the previously published article: Unique research project in polder Oud Ade.

Text: Hilde Pracht

Video: Charlotte Ellerman

The partners

About Land van Ons
Citizen's cooperative Land van Ons ('Land of Us All') purchases agricultural land to restore biodiversity and landscape together with farmers. Every citizen can buy a piece of agricultural land through Land van Ons and thus support the restoration of biodiversity and the landscape. 

About Holland Rijnland
Holland Rijnland is a collaboration between thirteen municipalities in the Leidse region, the Duin en Bollen Region and the Rijn and Veen Region. Together they improve the quality of living, working and learning for residents, entrepreneurs and social partners. 

About Leiden University - CML
Researchers of the Institute of Environmental Sciences Leiden (CML) investigate biodiversity in so-called Living Labs. Citizens can participate in the research and together with researchers and other stakeholders, investigate the conditions for, for example, a healthy living environment, food production and biodiversity.

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