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Background and Purpose: This paper deals with the results of the investigation of the selected heavy metal contents in forest soil in the region of an abandoned mine. The analysis of the forest ecosystem soil on the Medvednica Mountain was conducted in the region of the so-called “French Mines” (FM). The elements selected for analyses were cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) because of their toxicological characteristics. Material and Methods: In the investigated area - five entrances of the FM - composite topsoil samples (0–5 cm) were taken. Those samples were compared to the control samples which were taken outside the area affected by mines. The soil samples were analysed for the following parameters: pH, particle size distribution, organic C content and pseudo-total mass fractions of the selected heavy metals. The heavy metals were determined by atomic emission spectrometry with inductively coupled plasma (ICP-MS). Results and Conclusion: The results reveal that the soil is locally polluted, i.e. the highest mass fraction values of these four heavy metals were found in the area of the FM. Average pseudo-total fraction of Cd in the analysed topsoil samples was in the range of 0.17–4.41 mg·kg−1 (median: 0.97 mg·kg−1). Cu was found in the range of 4.54–1260 mg·kg−1 (median: 45.7 mg·kg−1). In the case of Zn, mass fraction values were found in the range of 36.8–865 mg·kg−1 (median: 137 mg·kg−1). Finally, average values of the pseudo-total fraction of Pb were found in the range of 58.4–12000 mg·kg−1 (median: 238 mg·kg−1). The results reveal that mining activities leave consequences on soil for a long time.

This paper presents the results of the preliminary testing of the selected trace elements in the soils of several parks in the city of Zagreb, Republic of Croatia. In each park, the samples were taken from several points-at various distances from the roads. The samples were taken at two different depths: 0-5 and 30-45 cm. Composite samples were done for each sampling point. Microwave-assisted wet digestion of the soil samples was performed and the determination by ICP-AES technique was done. Results obtained for Al, As, Ba, Mn, Ti, V, and K are in a good agreement with the results published in the scientific literature so far. The mass fraction values of Cd, Cr, Cu, Ni, Pb, and Zn are somewhat higher than the maximum values given in the Croatian Directive on agricultural land protection against pollution. Be, Mo, Sb, Se, and Tl in the samples were present in the concentrations that are lower than their method detection limit values.

Pinus halepensis (Mill.) is the most widely distributed and abundant Mediterranean pine, as well as one of the species most affected by wildfires in Europe. The objective of this study was to develop and test an operationally useful fine fuel moisture prediction model for P. halepensis needle litter below the fibre saturation point, where flammability increases rapidly with decreasing moisture content. The predictive ability of the hourly Fine Fuel Moisture Code (FFMC) was also evaluated. Even though the hourly FFMC model is designed for pine litter, it consistently over-predicted moisture content of P. halepensis needle litter and could not track the rapid moisture change during the day. Experimental measurements of equilibrium moisture content and response time of dead P. halepensis needles were used to modify the hourly FFMC model. The modified model performed better than the hourly FFMC model on all evaluation parameters, with a mean absolute error of 1% moisture content. Our results suggest that fine fuel moisture prediction models should be species-specific in order to achieve the accuracy needed for precise prediction of fire behaviour.

Like in other types of forests the greatest changes in the soil of floodplain forest stands occur during their regeneration. These changes are manifested as changes in the content and dynamics of organic matter in the soil. Research was conducted in oak and ash floodplain forests in the eastern part of Croatia and in southern Moravia in the Czech Republic. The results showed that the type and extent of these changes depended, in addition to environmental factors, also on the technology of forest regeneration. The natural regeneration of oak in floodplain forests of Spacva (eastern Croatia) protects soil from dramatic changes in soil by successive regeneration felling and that it retains the plant cover permanently. The weight of organic matter on the soil surface is increased after regeneration till the period when the effect of thinning becomes evident (about 70 years). In the surface mineral layer of soil the pH value increases after shelterwood felling. Stand regeneration with clear-cutting results in a rapid change in the conditions of surface humus accumulation and decomposition. The process of organic residue accumulation is interrupted in the clearings. In the preparation of soil/site by ploughing, the concentrations of nitrogen and carbon slightly decrease. The management impact depends on the method of site preparation for the establishment of a new stand. The selection of a method of the floodplain forest regeneration (particularly of oak) is markedly dependent on actual ecological conditions and on ecological and historical experience of the given region.