dr.ir. TPM (Thijs) Fijen

dr.ir. TPM (Thijs) Fijen

Assistant Professor

In my research I focus on the benefits and contributions of biodiversity to agriculture so that biodiversity conservation in agricultural landscapes improves. Biodiversity contributes in a myriad of ways to agriculture. For example, soil biota decompose plant residues, symbioses with fungi improve the water balance, and natural enemies prey on pests. One of the most visible and tangible ecosystem services that biodiversity delivers is the pollination of crops. Two-thirds of the crops in the world are (partially) depending on pollinators, mainly insects, for their crop yield. Despite the importance of these pollinators, only few farmers are actively protecting, or managing for, pollinators. My research can be divided in two global themes: the contribution of wild pollinators to crop yield, and can diversifying crops contribute to biodiversity conservation?

The contribution of wild polliantors to crop yield

Many studies have shown that pollinators contribute substantially to the crop yield, but actively managing for these pollinators is rare. The likely cause is that the contribution of wild pollinators is underestimated compared to all the other tools farmers have to increase corp yield. The easiest example is that farmers are more likely to increase their fertiliser inputs, rather than managing for more wild pollinators. By comparing the contribution of wild pollinators to the contribution of, for example, fertiliser, irrigation or managed pollinators, the contribution of pollinators can be put into perspective. In this way I provide convincing arguments for farmers to actively protect biodiversity

Forgotten crops: can diversifying crops contribute to biodiversity conservation

In the last century, we have lost many crop species in the Netherlands, mostly because other crops were more profitable. In particular, we have lost leguminous crops such as red clover, lupin and field bean, but also forgotten crops like buckwheat and flax. We know from museum studies that some species of bumblebees made abundant use of these crops, and with the crops, these bumblebees are now (almost) extinct in the Netherlands. In several projects, I contribute to the knowledge of the crop pollination of these forgotten crops such as lupin and buckwheat, so that the cultivation can gain ground once again. My ambition is to bring back the bumblebees once lost with the use of these crops.

Personal background

Since I was young I have been a fanatic birdwatcher, and I have specialised in identification and recording of bird sounds. Birds have opened up my eyes for everything that is out there in nature. It may therefore not be a surprise that I have studied both my BSc and MSc in Forest and Nature Conservation at WUR. After a few research stays in other institutes during my MSc, I stayed at WUR. As an ecologist with expertise in agricultural systems I try to make biodiversity conservation in agricultural landscapes mainstream, with benefits for everybody.