Medicinal Plants in Semi-Natural Grasslands: Impact of Management

Abstract

Background: Semi-natural grasslands as valuable ecosystems are significant for their high biodiversity, cultural importance and landscape values. Quantitative information about medicinal plants in semi-natural grasslands facilitates the evaluation of ecosystem services of these plant communities. Methods: Different literature sources and floristic inventory databases were used to assess the ratio and frequency of medicinal plant species in several Estonian grassland types and the impact of management on these values assessed both in Estonian and Japanese case studies. Lists of medicinal plant species according to different definition scenarios is included as Supplementary Material. Principal Component Analysis was applied for environmental preferences of medicinal plant species compared to other vascular plant species in the semi-natural grasslands.Results: The ratio of medicinal plant species in local total plant species list was the largest in alvars, followed by floodplain and wooded meadows. The average number of medicinal plant species per study plot in wooded meadows and alvars was about twice that found in naturally growing broadleaved forest (according to the most detailed MP species list 7.2, 7.8 and 4.3, respectively). Fertilization of Estonian wooded meadows had no significant impact on medicinal plant species ratio, but decreased the proportion of medicinal plant biomass in total yield. Estonian coastal meadows had a short list of medicinal plant species and the impact of management quality depended therefore on adopted definition scenario. In Japanese Miscanthus sinensis grassland case mowing or burning+mowing combination should be preferred to favor medicinal plant species number. Principal Component Analysis revealed that MP species are more drought-tolerant, common and anthropophyte than the rest of studied grassland species.Conclusions: Alternative usage of herbaceous plant species from semi-natural grasslands is a promising option to achieve sustainable development goals and increase public awareness. Further close cooperation of ecologists, economists and pharmacists is required to guarantee fair and sustainable trade of this ecosystem service in the future.