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Somay, L.

Publications and source records attributed to Somay, L..

3 recordsLinked to original sources

Effects of goldenrod (Solidago gigantea Aiton and S. canadensis L.) invasion on the wet meadow vegetation composition of Somogyfajsz wood pasture

In recent decades, restoring abandoned wood pastures are being rediscovered as an effective way to preserve biodiversity. Their restoration include the control of invasive plant species. In our study, we compared the vegetation composition of wet meadow patches uninvaded and invaded by giant and Canadian goldenrod in a wood pasture located in Somogyfajsz, Hungary. We sampled the vegetation of the wet meadows of the pasture in 16 pairs of 1 x 1 m invaded and uninvaded quadrats in June 2020. We studied the effect of goldenrod invasion on nature conservation value in terms of species diversity, origin of species, and Social Behaviour Types, and forage quality and quantity. The study revealed that goldenrod invasion had negative effects on species richness and community-level biomass in wet meadows, leading to a significant reduction in species diversity and total cover. Goldenrod invasion also impacted the richness and cover of both native and exotic species, with a decrease in richness but not cover, highlighting the competitive ability of goldenrods and their potential to alter vegetation composition.

ecology↗

Hungarian Grey cattle grazing outperforms mowing during wet meadow restoration following plantation forest clear-cut

Land-use change and ecological invasion are two main drivers of biodiversity loss, and the restoration of semi-natural wet grasslands is needed to tackle invasive species and re-establish grassland biodiversity on former forest plantations. This study tested the effectiveness of two widely used management techniques (grazing by traditional Hungarian Grey cattle and mowing once a year in August) as a restoration method of wet meadows in a former forest plantation invaded by goldenrod species in Central Hungary. We compared the vegetation composition of grazed, mowed, and reference areas with semi-natural wet meadow vegetation based on plant biomass, species richness and cover of species groups of species origin, life span, growth form, and social behaviour types of Borhidi determining the grazing value and the nature conservation value of the grasslands. We found that grazing by Hungarian Grey cattle resulted in a vegetation that was more similar to the reference wet meadows than mowing once a year in late summer. Grazing was superior to mowing in terms of goldenrod control, total species richness and cover, as well as the abundance of natives, perennials, herbs, and legumes. However, in the grazed area, we detected more disturbance-tolerant and annual species than in the mowed area. Despite the improved vegetation condition in the grazed area, we identified substantial disparities between the grazed and reference areas after three years of grazing. Based on our results, we advise using continuous extensive grazing to restore and maintain semi-natural wet meadows.

ecology↗

Oak regeneration at the arid boundary of the temperate deciduous forest biome: insights from a seeding and watering experiment

Temperate deciduous forests dominated by oaks cover extensive areas in European lowlands. These ecosystems have been under intense anthropogenic use for millennia, thus their natural dynamics, and their regeneration in particular, is still not well understood. Previous studies found that pedunculate oak (Quercus robur), one of the most widespread and abundant species in European deciduous forests, regenerates in open habitats and forest edges, but not in closed forest interiors. However, these observations usually come from the core areas of the biome, and much less is known about such processes at its arid boundary, where limiting factors may be different, and climate change may first exert its effects. In a full factorial field experiment, we tested the effects of different habitats and increased growing season precipitation on the early regeneration of pedunculate oak in a forest-steppe ecosystem in Central Hungary, at the arid boundary of temperate deciduous forests. We planted acorns into three neighbouring habitats (grassland, forest edge, forest interior) and studied seedling emergence and plant performance under ambient weather and additional watering for four years. In the grassland habitat, seedling emergence was very low, and no seedlings survived by the fourth year. In contrast, seedling emergence was high and similar at forest edges and forest interiors, and was not affected by water addition. Most seedlings survived until the fourth year, with no difference between forest edge and forest interior habitats in numbers, and only minor or transient differences in size (leaf number, height). The lack of oak regeneration in the grassland contradicts previous reports on successful oak regeneration in open habitats, and may be related to a shift from light limitation to other limiting factors, such as moisture or microclimatic extremes, when moving away from the core of the deciduous forest biome towards its arid boundary. The similar number and performance of seedlings in forest edges and forest interiors may also be related to the decreasing importance of light limitation. The above-average precipitation in the year of seedling emergence (2016) might be a reason why watering had no effect on oak regeneration. Overall, our results highlight that oak regeneration and thus forest dynamics may be limited by different factors at a biome boundary compared to its core areas. Indeed, this very simple mechanism (inability of oak regeneration in grassland habitats) may contribute to the opening up of the closed forest biome, and the emergence of a biome transition zone.

ecology↗