ľ�ϸ���Ӱ��

Patrick Jansen has been appointed as Professor of Wildlife Ecology and Nature Restoration at Utrecht ľ�ϸ���Ӱ��. Jansen and his team, including Marijke van Kuijk and Joeri Zwerts, aim to bridge the gap between fundamental ecological research and practical challenges in nature conservation and restoration. Their work focuses on questions such as how to best connect natural areas and how to integrate nature with other functions, such as recreation.

Ecological knowledge does not always align well with practice. As a result, for those involved in nature management and policy it is sometimes unclear how to apply such knowledge effectively. Jansen offers an example.

Jansen: “We know that nature in the Netherlands is declining due to various factors, including nitrogen deposition, drought caused by drainage and possibly pesticide effects and human disturbance. But perhaps the biggest issue is the lack of space for nature and the poor connectivity between natural areas.

Imagine if the government decided to convert ten percent of agricultural land into nature to halt this decline. How should that space be used most effectively? Should we focus on expanding existing natural areas, or would it be better to improve connections between them? And if we choose the latter, what is the best approach? Do we create a few large, robust corridors, or many smaller ones? Or should we restore the ‘green-blue veins’ of the landscape by reintroducing hedgerows and ditches?”

The population density is high and nature is struggling. What options do we have under these circumstances?

Similar questions arise in other countries as well. In Indonesia, for instance, vast forest areas are being cleared for palm oil plantations. The Indonesian government wants to preserve a certain percentage of forest. But where should those forests be maintained, how large should the protected areas be, and how can they be effectively connected?

Multifunctional landscapes

Jansen will also explore ways to combine nature with other functions to create multifunctional landscapes. Can we protect nature while, for instance, also restoring historical cultural landscapes and providing more space for sports and recreation?

The Netherlands serves as a great testing ground for such questions, the ecologist points out. “The population density is high and nature is struggling. What options do we have under these circumstances?”

National Ecological Network

Jansen focuses on, among other things, the National Ecological Network (in Dutch: Ecologische Hoofdstructuur or EHS), which was introduced in the Netherlands in 1990. “The EHS was one of the world’s first national ecological networks and served as a model for other countries,” he explains. “Civil servants translated strong scientific theory into policy, focusing on larger natural areas and better connectivity. It will be fascinating to evaluate what this policy has accomplished after 35 years.”

Ecological problems shouldn’t be addressed by ecologists alone.

Making connections

Jansen himself has worked extensively in Panama. There, he experienced that working on issues related to nature, such as restoring connections between natural areas, requires considering many other aspects. “Ecological problems shouldn’t be addressed by ecologists alone,” Jansen says. “It needs to be done in a fair, socioeconomically responsible, and economically viable way. Furthermore, everything must be legally grounded to ensure permanent solutions. It is much more than just ecology, and problems must be tackled in collaboration with people from other sectors. That means you need to bring together teams, groups, and organizations.”

Rewilding

Another area Jansen is working on is rewilding. Rewilding seeks to restore natural processes to boost biodiversity and stimulate ecosystem functioning. While the concepts behind rewilding are logical and plausible, Jansen says they have not yet been sufficiently tested to see if they actually work in the current context of human-dominated landscapes.

One of Jansen’s interests is the role of dead wood in nature. Jansen: “Compared to truly wild forests, our forests are quite empty. An important part of forest biodiversity depends on dead wood, primarily beetles and fungi. Forest managers who recognize this are exploring various ways to reintroduce dead wood into forests. Not only do they leave diseased and dead trees standing or lying around, but they also intentionally kill trees to help the process along. This can be done in several ways, such as by damaging, uprooting, sawing them down, or even setting fire to the base of the tree. But which of these methods is most effective in bringing back beetles and fungi? And how does this depend on the surrounding landscape?”

So even though it is not a laboratory with Erlenmeyer flasks, you are still doing a form of experimentation.

Camera traps

Jansen and his team are also working on technology to use camera traps more effectively. By strategically placing camera traps in natural areas, you can not only identify which animals inhabit the area, but you can also determine their population density, or the number of animals per unit of area. With additional measurements and advanced data processing, it is possible to gather a wealth of information about mammals without needing to physically capture or disturb them.

With such technology, researchers can, for example, measure the impact of reducing crowding in a natural area. Jansen: “Imagine you have areas where specific measures are implemented. By using camera traps, you can track the distribution of animals in time and space both before and after the measures are taken. If you also set up cameras in control areas where no changes are made, you will get a clear picture of the measure’s effect on the animals. So even though it is not a laboratory with Erlenmeyer flasks, you are still doing a form of experimentation.”