Twenty years of Baltic Boreal coastal meadow restoration: has it been long enough?

Abstract

The restoration of a threatened type of seminatural grassland-the Baltic Boreal coastal meadows-began in Estonia in 1997. The main causes of degradation of these communities were land abandonment and overgrowth by reed. In 2015, we resurveyed 14 sites and classified as (1) permanently managed or (2) restored before 2005, or (3) after 2005. In 2015, all sites were managed under the EU agri-environmental scheme and classified as permanently managed or restored before or after 2005. The resurvey focused on assessment of the long-term success of restoration, comparing the vegetation parameters of restored meadows with permanently managed meadows (which were considered as reference). Our study revealed that historical management patterns have an impact on the species richness of these habitats, as more species were found in historically mown meadows, even if the sites were restored by grazing. However, species richness was not an important indicator of coastal meadow recovery. The best indicators of restoration success are evenness and coverage of low-lying, light-demanding, salt-tolerant, wintergreen, cryptophyte, and hemicryptophyte plant species. Phragmites australis is a good indicator species for the habitat, as its abundance indicates poor habitat quality. The study indicated that the recovery of coastal meadow habitat from abandonment requires more than 15 years of restoration activities, and suggested the 3-year restoration period covered by conservation measures and funds is not enough. Therefore, we recommend that agri-environmental schemes should support additional restoration activities for recently restored meadows which are entering the management scheme.

Medicinal Plants in Semi-Natural Grasslands: Impact of Management

“…Our previous study has revealed that in coastal meadows plant species, number does not increase with long-term management [24] and in comparison with other types studied, only a small number of MP species were present here. Therefore, the interpretation of obtained results must be done carefully.…”

“…Most probably, such high variability was caused by very different managemant background and quality of our study sites. In our previous papers, we have demonstrated that both restoration quality and management acitivities have a very strong impact on local plant biodiversity [23,24]. If we deminished our study site selecion in each habitat type by half, almost half of the biodiversity of habitat type could be out of our database, and we recorded almost twice less MP species.…”

“…Most of the sites had been annually grazed by cattle and the management varied from permanently managed to recently restored. The division of these sites into three groups based on their management history and vegetation quality has been proved by their plant community characteristics [24] and we, therefore, continued the current study with the same "very good", "good" and "poor" management (vegetation quality) classes.…”

“…In order to fill the gap, we endeavored to find any publications with the lists of MP species that were available for the areas where we had previously performed our studies about the impact of management on SNG plant biodiversity [23,24]. Fortunately, we were able to detect three sources for Estonian conditions that have been published for different purposes.…”

Comparing Pixel- and Object-Based Approaches for Classifying Multispectral Drone Imagery of a Salt Marsh Restoration and Reference Site

“…The Zheng et al [52] study, where OB methods outperformed PB methods, was conducted in a sub-tropical (31 degrees latitude) salt and brackish marsh at the mouth of an estuary along the Yellow Sea, which had plant communities consisting of Phragmites sp., Scirpus triqueter, Carex scabrifolia, and Imperata cylindrica [78] (reeds, bulrushes, and cogon grasses, respectively); these plants are larger, with more showy inflorescences, than the plants of the Aulac marshes. On the other hand, Martinez Prentice et al's [50] study was conducted in a north temperate coastal wetland (58 degrees latitude) along the Baltic Sea, where the plant communities include moor grasses (Molinia caerulea) and rushes (Carex panicea) [79]. These Baltic coastal meadows include vegetation that resembles the grasses of the Aulac marshes in size and inflorescence.…”