Climatic conditions are extremely important for the start and spread of forest fires. Flammability and the spread of fire are sensitive to the interactions of variables within ecosystems, such as weather, fuel, and topography. Certain variables are highly significant for forest fires and are applied in various models, particularly the moisture content of potential fuel, and its flammability or combustibility. However, such these models cannot determine the true values of the required variables, unlike actual empirical research. Areas with the highest number of fires show significant variability and differences in air temperature, humidity, and precipitation. These factors have a strong influence on flammability, combustibility, and moisture content of Mediterranean species. This study analyses the flammability and combustibility of two Mediterranean species important for the Adriatic area in Croatia: climazonal holm oak (Quercus ilex L.) and Aleppo pine (Pinus halepensis Mill.) as an important conifer for afforestation and reforestation. The results of linear correlation coefficients of flammability of these species at the studied localities show a statistically significant and very strong correlation between flammability and the moisture content of the tested sample, with the exception of Aleppo pine on the island of Rab. The analysis of variance of combustibility showed that there were no statistically significant differences between nearly all variables tested. The results indicate the significant effect of live fuel moisture content on the flammability and combustibility of natural fuels.

Black pine (Pinus nigra J.F. Arnold) is one of the most important reforestation species for dry and rocky terrain in the sub-Mediterranean zone. Fire is an important factor in black pine stands that largely defines the distribution range of black pine and the floristic composition of its stands. Fire causes less damage during autumn or early spring when tree cones contain ripe seeds that can partially reforest burnt surfaces. Every fire is a potentially significant threat to forest habitats. There are many damages, from direct damages to wood mass and reforestation costs, to indirect ecological, edaphic, protective damages and the loss of biological diversity. The aim of prevention works in forestry is to reduce the number of fires and reduce burnt surface area per fire. Research was based on vegetation analysis performed on each experimental plot in a black pine stand. The assessment of fire severity was performed using the Canadian Forest Fire Weather Index (FWI). The assessment of the severity of fire indicates the suitability of conditions for the occurrence of forest fires, and enables sound and effective protective methods beginning with silvicultural works. The results indicate better quality stands in the higher parts of the sub-Mediterranean area. Taking into account the climatic parameter, the areas on the border with the continental climate have better habitat conditions for black pine. Also, attention should be focused on 2012 and 2015. High values (Figure 13 – 16.22, Figure 11 – 6.99, Figure 8 – 8.38, Figure 7 – 12.02 and 12.25, Figure 5 – 8.32) indicate the overlapping of extremely dry periods and extremely high summer temperatures, and probably a strong wind influence that further increases the index. Fire severity assessments indicate the suitability of conditions for the onset of fire.

This study outlines research performed on experimental plots established in forest plantations and in natural black pine forests. The objective of the study was to determine the habitat factors that have the greatest impact on the growth and development of natural black pine forests and black pine forests plantations upon the return of climatozonal vegetation. Plots 625 m² in size were selected and vegetation inventories made, and the structural elements of black pine plantations examined. Multivariate analysis found that elevation and slope were the two variables that had the highest positive correlation with the floristic composition of the vegetation. Furthermore, one of the goals was to determine the differences with regard to reforestation with black pine. The analysis of the isolated experimental plots showed a clear grouping of plots according to habitat factors. The differences in the synecological factors in the research area resulted in the presence of sub-Mediterranean, epi-Mediterranean and eu-Mediterranean elements within the black pine forest plantations. This also reduces the risk of the occurrence and development of large wildfires.

Vjetrozaštitni pojasi uspostavljaju se kao barijere od redova stabala ili grmlja koje se sade s namjenom reduciranja brzine vjetra, smanjenja evapotranspiracije, zaštite od eolske erozije, istovremeno izravno se koriste za zaštitu...

U vegetacijskom smislu, šume hrasta crnike sastavni su dio mediteranske regije, a hrast crnika se pojavljuje kao edifikator klimatogene zajednice vazdazelenog pojasa. Tijek razvoja vegetacije u smislu progresije i regresije prikazan je...

SEEFOR - South-East European Forestry