Ramat Hanadiv 1980’s Fire Outbreak

Post-Fire Vegetation Dynamics and Vegetal Potentialities 
Jean-Marc Dufour-Dror
 
This research studied the spatial extent of the May 1980’s fire and the vegetation dynamics within the burnt area, in order define the vegetation potential in the burnt area. The spatial extension of the fire has been determined according to the actual distribution of the in situ remains of burnt branch and trunks of Phillyrea latifolia specimens. These limits were drawn on a recent aerial picture of Ramat Hanadiv, then digitized into a computerized spatial data layer. This GIS map enabled us to calculate the size of the area burnt in May 1980: 25.3% of the park area. It was also determined that the fire outbreak has expanded in 6 different sites. A medium close matorral dominated by Phillyrea latifolia and Calycotome villosa has developed within the study area since 1980. The analysis of the matorral structure and floristic composition shows that this vegetation formation is gradually changing from a progressive dynamic stage mainly resulting from the resprouting process – to a stage of auto-succession. The matorral current dynamics does not imply that it is able to develop spontaneously toward a forest structure. The analysis of the potential of vegetation within the study area suggests that the present matorral should be considered as the current potential of vegetation, while special vegetation surveys carried into the burnt area and its surroundings suggest that the abiotic conditions may not prevent the development of a Quercus calliprinos oak forest structure. This hypothesis implicates a necessary distinction between the “”current potential of vegetation”” resulting from an anthropogenic matorralization process, apparently irreversible and the “”environment potential of vegetation”” which may be a sclerophyll oak forest. This interpretation is presented as alternative hypothesis compared to a former one suggesting that the under-development of Quercus calliprinos at Ramat Hanadiv may be related to the characteristic water regime due to local geological-hydrological conditions.