What Are the Effects of Cattle Grazing on Conservation and Forage Value Across Grazing Pressure Gradients in Alkali Grasslands?

Studying the effects of grazing pressure on species composition, beta diversity and yields is important for conservation purposes as well as for grassland management. The case study area in Hortobágy, which is one of the largest continuous grassland areas in Europe, has been managed for centuries by grazing of Hungarian grey cattle. The effect of grazing pressure was investigated in terms of distance from the livestock enclosure (50 m, 250 m, 500 m, 1000 m, and 1700 m) and in an ungrazed control area on dry and mesic alkaline grasslands in spring and autumn of 2024. In both types of grasslands at each distance, species composition and mean plant height were recorded in six 4 × 4 m plots. Overall, in both seasons the control areas were the poorest in terms of species richness. Among the grazed areas in both grassland types the ones at 1700 m distance had the lowest number of species. The species richness of mesic grassland decreased linearly with distance. The dry grassland showed a polynomial trend and was more species-rich at all distances than the mesic grassland. Green yield was the highest in the dry grassland at 250 m in spring and at 50 m in autumn, while in the mesic grassland it was highest at 1700 m in spring and between 500 and 1700 m in autumn. Forage quality in dry grassland was lowest at 50 m and highest between 500 and 1000 m. In mesic grassland, this parameter was equalized at all distances. The highest Simpson diversity was found at a distance of 500–1000 m from the livestock enclosure in both types. It is advisable to evaluate separately the spring and autumn characteristics of the alkaline grasslands, as there may be significant differences between them. Overall, it can be concluded that alkaline dry grasslands are particularly suitable for grazing because of their species composition and their good tolerance to grazing. Alkaline mesic grasslands are poorer in species and more sensitive to grazing; consequently, mowing or mixed utilization should be considered.