Factors affecting persistence of terrestrial orchids in wet meadows and implications for their conservation in a changing agricultural landscape

We examined the occurrence of Dactylorhiza majalis, the most abundant terrestrial orchid species growing in rapidly disappearing wet meadows, at 50 historical sites for 3 years. We aimed to find the most frequent reasons for its recent extinction at many sites. We found that the main reasons for its extinction were absence of mowing, intensive fertilisation and washouts of fertilisers from fields nearby. At extant sites, we studied its biometric characteristics and composition of surrounding vegetation, to determine factors affecting its persistence. Bad performance of persisting populations of this species was associated with prevalence of grasses, low May temperatures and absence of mowing. This confirms, at metapopulation level, what has previously been observed at the level of individual populations. We suggest that the system of agricultural subsidies in the country should change towards more sensitive allocation of funds to those farmers, who will adopt the appropriate management of wet meadows and their surroundings. (C) 2003 Elsevier Ltd. All rights reserved.