BIOCORE: Conservation and restoration of fragmented biodiversity hot spots: Calcareous grasslands of South-Belgium



One of the most species rich plant communities in the world at a small scale are calcareous grasslands (up to 50 plant species/m²). Moreover, a very high arthropod diversity is associated with this extraordinary plant species richness. These grasslands were once widespread in the hilly calcareous regions of Western Europe but due to changes in agricultural use (i.e., abandonment of grazing by sheep and cattle and/or fertilisation) their extent has decreased dramatically. In Belgium, the calcareous grasslands of the Viroin valley are the country's most species rich ecosystem and they can be described as so called biodiversity “hot spots”. As in the rest of Europe, since World War II, urbanisation, abandonment of grazing practice and fertilisation resulted in a dramatic decrease of the grassland area and an increase of the isolation of the remaining grassland fragments.

Project description

Fragmentation is the process through which a formerly continuous habitat turns into patches of varying size, isolated from each other by hostile land. The habitat fragmentation process includes two important components: the reduction of the patch size of the resulting habitat fragments on the one side and the increasing spatial isolation of the different fragments from each other on the other. The result of the fragmentation process in the Viroin valley is a number of chalk grassland ‘islands’ in an ocean of hostile habitat consisting of woodland and intensively used agricultural land.


The major aim of the proposed research is to provide guidelines for the conservation and the remediation of the biodiversity of the system of fragmented calcareous grasslands of the Viroin Valley. We will focus on the conservation and restoration of plant species richness and of butterfly species richness. Plant species are the basic components of each ecosystem as they provide food and shelter for heterotrophic organisms. Butterflies were selected because they are relatively easy to study and they respond quickly to environmental changes and to changes in plant composition. Hence they are very suitable as indicator species.

The Viroin grasslands are worth studying not only because of their particularity as biodiversity “hot spots” but also because of their general representativeness as a fragmented ecosystem. Due to the unique spatial arrangement of the habitat fragments -up to 70 relatively homogeneous grassland fragments along a continuous gradient of size and isolation, located in an ocean of hostile cultivated or reforested land- the ecosystem studied can be considered an ‘open air laboratory’ extremely fit for the in situ study of the effects of habitat fragmentation on biodiversity. This will enable us to extend our methodological and our theoretical framework to other fragmented ecosystems.


We will study the effects of grassland fragmentation on the three primary descriptors of the community structure of plants and butterflies. This means that we will study the effects of fragmentation on 1) the species number of the fragments, 2) their community composition and 3) the performance of a selection of individual species. Most attention will go to the latter, i.e. the population level. The performance of individual species will be quantified by their demographics, population genetics and phenotypic fitness. Special attention will be paid to the integration of the plant and butterfly data. Secondly, using our insights in the ecological consequences of the habitat fragmentation process, we will provide clear guidelines to conserve the present biodiversity, especially with respect to minimal population sizes and the connectivity between habitat fragments. We will also provide a general methodological framework to deal with the remediation of habitat fragmentation.

Interaction between the different partners

The added value of this research project lays in the first place in the quite unique multidisciplinary approach of a representative fragmentation problem at the landscape scale. The close co-operation of molecular geneticists, plant ecologists and entomologists will generate an important added value. There is a growing consensus among scientists that the conservation of biodiversity requires an integrated approach covering the requirements of a large number of different species. The limited exchange of information between scientists is constraining successfully integrated conservation management.

Expected results and/or products

This project will bridge the gap between the study of the effects on fragmentation on the one side and guidelines for remediation on the other.
Specific research results are:

• a serious step in the direction of the conservation and restoration of Belgium’s most important biodiversity hot spot;
• a methodological framework for studying the effects of fragmentation on species richness and population viability in a multidisciplinary way;
• an insight in how habitat fragmentation affects species richness through its effect on population viability;
• a practical toolbox (a decision aid tool) with guidelines to remediate habitat fragmentation and to restore biodiversity in fragmented habitats.

We have the ambition to publish our research results in international peer reviewed journals on the one side and in magazines that reach a broader audience of rural planners, policy makers and local nature conservation organisations on the other.
We have also built a publicly accessible web site where the results of the research can be accessed.



Plant Ecology Team (co-ordination)
Most of the research at KULeuven-FNLR concerns the effects of forest fragmentation on forest plant species and focused on the species richness and species composition of these forest fragments and on the population dynamics of the plant populations. Also research concerning the ecological restoration of forests has been a major topic of the unit.

Butterfly Genetics and Butterfly Ecology Team
Since 1994 the group has initiated a series of projects on the ecology and genetics of populations from different taxa. The general aim is to investigate which mechanisms are responsible for the adaptation of populations to selective pressures of a changing, heterogeneous environment. Research topics are: (1) which ecological and/or genetic processes determine the structures of local populations, (2) the importance of dispersal, (3) the relations between genetic diversity/effective size of populations and genetic differentiation/spatial isolation and (4) how individual quality affects population structure and functioning.

Plant Genetics Team
The section of applied plant biotechnology of the department of plant genetics and breeding has long-standing experience in the characterisation of complex plant populations using molecular markers. Our current research in this field focusses on the characterisation of breeding populations and wild relatives, on the conservation of natural plant populations and on variety identification. Molecular marker techniques such as AFLP, SSR, RFLP, CAPS and STS are currently used at those laboratories.

Contact Information

Website of the network:


Olivier Honnay
Jan Butaye
Martin Hermy
Katholieke Universiteit Leuven (KULeuven)
Laboratorium voor Bos, Natuur en Landschap
Vital Decosterstraat 102
B-3000 Leuven
Tel: +32 (0)16 32 97 21
Fax: +32 (0)16 32 97 60


Michel Baguette
Sofie Vandewoestijne
Université Catholique de Louvain (UCL)
Centre de recherche sur la biodiversité (BDIV)
Unité d’écologie et de biogéographie (ECOL)
Biologie de la Conservation des Populations (BCOP)
4, Croix du sud
B-1348 Louvain-la-Neuve
Tel: +32 (0)10 47 34 95
Fax: +32 (0)10 47 34 90

Isabel Roldán-Ruiz
Els Coart
Ministerie van de Vlaamse Gemeenschap
Centrum voor Landbouwkundig Onderzoek – Gent (CLO)
Department of Plant Genetics and Breeding (CLO-DvP)
Caritasstraat 21
B-9090 Melle
Tel: +32 (0)9 272 28 82
Fax: +32 (0)9 272 29 01

Users Committee

Dirk Maes - Institute for Nature Conservation
Pierre Gerard - Nature, Forest and Wood Research Centre
Jean-Pierre Collin - Parc Naturel Viroin Hermeton
Gregory Mahy – FSAGx - Laboratoire d'écologie


aflp, Anthyllis vulneraria, calcareous grasslands, community composition, habitat fragmentation, landscape ecology, population genetics, SPSD II, PODO II, PADD II, EV26


Belgium {Geographical scope}
Agricultural {Habitat type}
Dry and Sub-humid Lands {Habitat type}


Name Role Amount
Science for Sustainable Development unknown


Name Role Start End
Coart, Els member 2003-01-01 2006-04-01
Roldán-Ruiz, Isabel member 2003-01-01 2006-04-01
Baguette, Michel member 2003-01-01 2006-04-01
Vandewoestijne, Sofie member 2003-01-01 2006-04-01
Honnay, Olivier co-promotor 2002-02-01 2006-04-01
Butaye, Jan co-promotor 2002-02-01 2006-04-01
Hermy, Martin co-promotor 2002-02-01 2006-04-01


Name Role Start End
Plant Ecology and Nature Conservation leader 2002-02-01 2006-04-01
Réponse des espèces et des communautés aux mécanismes de l'environnement member 2003-01-01 2006-04-01
Applied Genetics and Breeding member 2003-01-01 2006-04-01

created:2011-12-14 14:18:59 UTC, source:web

© 2012 by the Belgian Biodiversity Platform