Long-term grazing effects on secondary succession of vegetation in old fields at the University Forest of Taxiarhis in Chalkidiki, northern Greece

Grazing is one of the most prevalent worldwide land uses, which can affect secondary succession of vegetation in abandoned fields. The aim of this study was to investigate the long-term effects of grazing on secondary succession of old fields in α mountain area of northern Greece. In order to meet this purpose, adjacent grazed mainly by goats and protected plots of an old field abandoned for 20 years were chosen in the village community of Taxiarchis, Chalkidiki, nortern Greece. In each of the two fields plant cover and biomass were measured. Plant species were classified into functional groups based on botanical family, life cycle, life form and photosynthetic pathway. It was found that grazing pressure was heavy. Plant cover and biomass were significantly decreased due to heavy grazing. Annual species were favoured at the expense of perennials, therophytes and geophytes at the expense of hemicryptophytes and warm season at the expense of cool season plants while woody species were suppressed. It is indicated that heavy grazing pressure by goats leads to earlier stages of secondary succession of the vegetation in old fields.