My main research project concerns the conservation biology of rare Belgian plants that are protected by the European Habitat Directive. This multidisciplinary research is conducted in collaboration with scientists from within and outside the botanic garden. It includes the determination of their past and current distributions; their status; demographic trends; threats to their existence; their genetic variability, as well as their ecology and phytosociology. The first species I studied was the rare Helosciadium repens (≡ Apium repens), which is a small and creeping member of the Apiaceae. Its demographic monitoring has proven challenging and time consuming because of its small size, its clonal growth with hidden connections, and its persistent seed bank. Another difficulty is the correct identification of the species, as there are morphological intermediates with the closely related H. nodiflorum. I am studying the morphological variation of both species and of related species, compared with their genetic variation. I also study Luronium natans (Alismataceae), an aquatic plant that is declining even though temporary populations do spontaneously occur. This pioneer species appears to be dependent on a good water quality and on an adapted management of the water bodies.
A second research line consists of floristic studies in Belgium. I have made numerous plant inventories for the Flemish plant atlas (Van Landuyt et al. 2006), of which I am a co-author. Being interested in the development of floristic biodiversity in response to land management, I have initiated a study of roadside vegetation in Vlaams-Brabant that is “ecologically mown”. I am also investigating the (sub)spontaneous flora in the domain of the National Botanic Garden in Meise: beside indigenous species many neophytes have been found. A monitoring scheme has been developed, in part to monitor collection escapes (ergasiophygophytes). Another type of neophytes that I have become interested in are wood lawn neophytes, historical relics from English style landscape gardens. I am also planning a new project for an “All Taxa Biodiversity Inventory” and monitoring (ATBI+) in the domain. This aims to quantify the biodiversity by making inventories of species from as diverse organism groups as possible, taking into account the different habitat and management types