Population biology of the threatened, long-lived perennial
Scorzonera humilis (Asteraceae)

Project leader: Guy Colling (Department of Population biology - Databases, Museum of Natural History, Luxembourg (e-mail).
Collaborators: Diethart Matthies (Department of Biology, Plant Ecology, University of Marburg) (matthies@mailer.uni-marburg.de) Claude Reckinger (Scientific collaborator of the Museum of natural history) (e-mail).

Scorzonera humilis is a long-lived, herbaceous perennial characteristic of wet, nutrient-poor hay meadows and wet heathlands. It was formerly a common plant but has strongly declined in the last decades and is now endangered in many parts of Europe. The main reasons for its decline are the use of fertilisers, drainage and land reclamation, and the lack of suitable management in nature reserves. Many populations are now very small and isolated due to intense fragmentation of the remaining habitats.

In this project the complete life cycle of Scorzonera humilis is analysed and the spatial and temporal patterns of demographic and genetic variability investigated. These studies are complemented by experiments to test hypotheses about the relationship between management, environmental factors, genetic variation, population size, establishment and extinction risk. The data from the studies and experiments will provide the basis for population and risk assessment models, and will also serve as a basis for long-term monitoring. They should help to improve existing extensification schemes aiming to restore plant diversity in grasslands.

Publications

Colling, G., Matthies, D. and Reckinger, C. 2002. Population structure and establishment of the threatened long-lived perennial Scorzonera humilis in relation to environment. - Journal of Applied Ecology 39: 310-320.

Colling, G., Matthies, D. 2004. The effects of plant population size on the interactions between the endangered plant Scorzonera humilis, a specialised herbivore, and a phytopathogenic fungus. - Oikos 105: 71-78.