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For the improvement and maintenance of the desirable ecological value of semi-natural grass-lands, it is necessary to manage them in a way which maintains their structure and their long-term functioning. This way is the extensive grazing in the case of the majority of grasslands situated on the Eurasian low��lands. Defoliation and biomass removal are among the most important effects of grazing on the vegetation, while the sufficient quantity and quality of plant biomass is an important ecosystem service for animal husbandry. In order to maintain the long-term functioning of pastures, it is important to gather information about the amount of consumed biomass and the dietary choice of the livestock. Therefore, we studied the direct effects of grazing on species-rich meadow steppes in Central-Hungary and the underlying mechanisms of dietary choice of cattle, using a trait-based approach. We asked the following questions: (1) What are the direct effects of grazing on the various biomass fractions (litter, mosses, forbs and graminoids)? (2) Which traits distinguish the preferred and non-preferred vascular plant species? The studied pastures were divided into two adjacent sites, which were managed differently in the study year: the grazed sites were managed by grazing for three months before the sampling date, while the control sites remained ungrazed until the sampling. In the previous years, the whole study area (i.e., each site) was grazed with moderate grazing intensity. We collected above-ground biomass samples, and measured leaf traits and shoot nitrogen concentration of the plants. The consumption of the litter and moss biomass was negligible, while the reduction of the live biomass of vascular plants was 65%. Grazing significantly decreased the flowering success of plants. Cattle consumed species characterized by high specific leaf area and high nitrogen concen-tration. Based on our results, we emphasize that in order to ensure the reproduction of most plant species in the long term, it is unfavourable to graze an area every year in the same period. Instead, it is recommended to use grazing in a mosaic spatial and temporal pattern. The livestock carrying capacity of an area and the long-term manage-ment of grasslands can be carefully planned based on measurements of biomass and the nutritional value of plants, which is well indicated by some easily measurable plant properties such as specific leaf area and the nitrogen concentration of species.

In Central Europe many grasslands are threatened by the abandonment of traditional land use, lead- ing to litter accumulation and encroachment of competitive grasses, woody and invasive species, ulti- mately causing the loss of biodiversity in the long run. Resumption of traditional management practices might reverse the negative effects of abandonment, but can be challenging in the current socio- economic context, especially in habitats providing poor-quality forage, such as fen meadows. Given the limited resources of nature conservation agencies, it is crucial to find proper alternative management options to tackle the complex conservation problems these habitats are facing. We studied three sampling sites in an abandoned fen meadow in West Hungary that are subjected to litter accumulation and the encroachment of competitive grasses, shrubs and the invasive giant golden- rod (Solidago gigantea). In a baseline survey in 2019, we evaluated the relationship between the above- mentioned threat factors and conservation value indicators (i.e. Shannon diversity, herbaceous species richness, cover of forbs, number of flowering shoots of forbs, naturalness score and forage quality). In a field experiment we used the BACI (Before-After-Control-Impact) design to study the effects of a traditional (mowing) and two alternative (mowing without hay removal, burning) conservation measures and no management (control) on the threat factors and conservation value indicators. We tested the short-term effects of these management types on all dependent variables measured in 2020 by using generalised linear mixed-effect models. In our study system the purple moor-grass (Molinia arundinacea) as dominant species had the most significant negative impact, affecting four out of the six conservation value indicators studied. Litter accumulation had significant negative effects on three indicators. We found that the single application of the tested treatments was not successful in reaching the conservation targets, neither in terms of mitigating the threat factors nor in increasing the conservation value indicators. Mowing and burning treatments both reduced the amount of litter, but the cover of Molinia (the strongest predictor of the conservation value indicators) was unaffected by all treatment types. As a consequence, we did not detect any effects of the treatments on the indicators of conservation value one year after the treatments. It is likely that repeated treatments are necessary to achieve positive changes in conservation value. Another possible explanation is that the applied treatments did not target the most influential threat factor, i.e. the encroachment of Molinia. Therefore, we recommend determining the most influential threat factors first before applying resource-consuming conservation management treatments in grass- lands facing multiple threat factors.