TitlePopulation dynamics of Orchis morio in the Czech Republic under human influence
Publication TypeMiscellaneous
Year of Publication2002
AuthorsJersakova, J, Kindlmann, P, Stritesky, M
Abstract

Many species of terrestrial orchids in Europe have been adapted to secondary forest-free area, meadows and pastures created by humans. Therefore, appropriate vegetation management of the site is essential for the orchid populations to persist. Orchis morio L. represents a formerly abundant vernal species. Its sites have been rapidly disappearing in the last four decades due to loss of habitats caused either by agricultural improvement of old hay meadows, or their abandonment. During the recent seven years we monitored 44 sites in South Bohemia (Central Europe), where O. morio populations still survive and established a field experiment, testing effects of different types of management on orchid population dynamics. We found that: (i) Irregular mowing strongly weakens and destabilises O. morio, populations. (ii) Absence of mowing has a serious negative effect on the number of flowering plants and leads to changes in species composition in the vegetation. (iii) Mowing once or twice a year improves flowering performance of orchid populations. (iv) Removal of litter seems to be indifferent to O. morio abundance. (v) Mowing once in two years is inappropriate for maintenance of this orchid species. (vi) O. morio reacts very quickly in a negative way to lack of mowing and very slowly in a positive way to management restoration.