POST-FIRE FUEL AND VEGETATION DYNAMICS IN AN UNGRAZED PHRYGANIC COMMUNITY OF CRETE, GREECE

Abstract

Phrygana is a widespread vegetat type in the eastern Mediterranean, mainly represented by Sarcopoteriwn spinosum dominated formations in the Aegean islands and Crete. The effects of overgrazing and frequent burnings on phrygana are relatively known by scientists, but limited attention has been paid to the functioning of these communities when grazing and fires are suppressed. The aim of this study is to investigate post-fire vegetation and fuel dynamics in an ungrazed S. spinosium dominated phrygana in northwestern Crete. Fuel was first analyzed according to shrub, herb, litter, and total load; then live and dead materials; and finally, 0-0.5 cm and 0.6-2.5 cm of leaf diameter classes. Vegetation was analyzed based on cover and life form composition and dynamics Also, species richness, diversity, and dynamics were investigated. One-way ANOVA was used to test for fuel and vegetation differences among sites, and Shannon-Wiener and Equitability indices were used to assess both diversity and evenness. Results showed a rapid reestablishment of both the vegetation (cover, life form, species richness and diversity) and fuel, as early as the 3rd and the 6th post-fire year, respectively. Fuel and vegetation were tremendously dominated by unpalatable and highly flammable dwarf shrubs, which smothered herbaceous plants. Species diversity was relatively low, indicating that few species crushingly structured the community by their high cover, while the remaining species were poorly abundant. The implications of the results in the context of a rational management planning of phryganic ecosystems are discussed.