In the Mediterranean regions, oak forests are commonly used for livestock grazing. However, it is well documented that livestock grazing is an essential factor that can affect the success of natural regeneration of oak and other woody species of the understorey. Consequently, it influences the composition and structure of oak woodlands. The main objective of the present study was to examine the effects of grazing intensity on characteristics of oak seedlings establishment (density, height, number of leaves) and on the diversity of the woody species seedlings. The research was conducted in open canopy Quercus frainetto woodland, grazed by a herd of 500 goats for eight months per year, located in Evros region, north-eastern Greece. The distance from a goat corral was used to represent relative grazing intensity. In May 2016, vegetation measurements were made along transects placed at 50, 150, 300, 600 and 1200 m from the goat corral, running perpendicular to four replicates. According to the results, increased grazing intensity significantly reduced the density, the plant height and the number of leaves of Quercus frainetto seedlings. Grazing intensity did not affect significantly diversity, evenness and dominance indices for the woody species seedlings. However, heavy grazing reduced species richness and the Chao1 index.

Understanding how the management practices of silvopastoral systems affect the long-term sustainability of oak ecosystems and what their influence is on nutrient cycling and plant community, is of great interest. The aim of this study was to examine the effects of relative grazing intensity on soil properties and on vegetation characteristics in an open canopy oak forest dominated by Quercus frainetto. The research was conducted in the area of Pentalofos, which is located in Evros region, north-eastern Greece and is grazed by goats. The distance from a goat corral was used to represent relative grazing intensity. In June 2011, soil and vegetation samples were collected along transects placed at 50, 150, 300, 600 and 1200 m from the goat corral, running perpendicular to three replicates. Soil measurements included pH, phosphorous (P) and nitrogen (N) concentrations while vegetation measurements included plant cover, species composition and diversity. Plant cover was not significantly different among grazing intensities. Species diversity, especially of the woody vegetation layer, was significantly higher in the light grazing intensity in comparison to both the heavy and the very light grazing. Heavy grazing reduced soil organic matter while it increased total nitrogen. Grazing intensity did not affect available P and soil pH. Light to moderate goat grazing could ameliorate floristic diversity and increase sustainability of oak forests in the Mediterranean region.

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