LIFE Herbages - Priority Actions for grasslands and meadows in Lorraine and the southern Ardenne - LIFE11NAT/BE/001060

Nutrient-poor grassland habitats and several of their characteristic plant species have reached a critical state in many European countries, including Belgium. The main reasons for this situation are: habitat fragmentation, forest recolonization due to abandonment of the traditional agro-pastoral activities, and the intensification of agricultural practices leading to eutrophication. There is now an urgent need to preserve, manage and restore these few remaining, often degraded, habitat patches. Part of this task includes the restoration of populations of critically endangered plant species that without intervention would not regenerate naturally due to restricted seed dispersal abilities and the absence of a persistent seed bank in the soil. In the framework of the EU-LIFE project “Herbages” (LIFE11 NAT/BE/001060), the Botanic Garden Meise, as a centre of excellence in ex situ conservation and plant propagation, has implemented population transplantations in the wild for four critically endangered species (Dianthus deltoides, Helichrysum arenarium, Arnica montana and Campanula glomerata). The aim is to increase the effective size of remaining populations (reinforcement) and to restore extinct populations (reintroduction) in order to improve connectivity in the landscape. For each species, seeds have been collected on a minimum of 50 individuals in two to four source populations in the closest possible similar habitats. In each source population, leaves were sampled on a minimum of 30 individuals in order to estimate population genetic diversity and structure. Soil samples were collected in the target sites to study the soil seed bank. Propagation protocols have been successfully developed for all target species. Prior to in situ transplantation, morphometric measures (vegetative plant size) were recorded on each individual. For each species, a population of 500 to 700 young individuals was transplanted in three or four different sites. Once in situ these plants were labeled and precisely mapped to facilitate their long-term monitoring. A demographic survey (e.g. survival, floral production, reproductive success, and population extension by clonal propagation or seedling recruitment) is recorded yearly on the field.

Trefwoorden:B270-plantenecologie