DIGITALNA ARHIVA ŠUMARSKOG LISTA
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| ŠUMARSKI LIST 9-10/1985 str. 41 <-- 41 --> PDF |
On the Entering of Areal Polutants into Beech and Fir Forests on the Dinaric Range of South-western Yugoslavia Summary A dieback of silver fir (Abies alba Mill.) has begun in natural miscelaneous beech-fir forests in Dinaric Mountains of Nortwest-Yugoslavia thirty years ago. Contemporary are affected an Croatia aproximately over 100 000 ha. Long time it was considered a cause of dieback was the impact of fir needle moth (Argyresthia fundella F. R.). Analogous to other European contries might be assumed the main stress factor are air pollutants. The dieback area is situated between two industrial regions with large air contamination (s. Fig. 1) and therefore exposed to remotely derived air pollutants. Further, it can be expected, the orographic precipitation and windy, cloudy conditions contribute essentially to higher dry and wet deposition. The purpose of this paper is to give first information about an influence of acid preciptitation on soil chemistry and about quantity of heavy mentals accumulated in organic layer of forest floor. 10 sites were selected in beech and beech-fir stands in Lika and Gorski Kotar at different elevations and orographic situations, the lowest at 350 m, the highest at 1230 m. The sample plots 3, 4 and 5 are located in imi&sion protected karst relief forms. 1 and 2 are exposed to inland, 6—10 in subalpine region oriented to seaboard side. Input and effects of pollutants were studied using the forest floor as a sink. It was made a comparison of the stemblow-water influenced »microhabitat« beneath old beech trees (with enriched pollutant concentrations) and the »maerohabitat« 2 od 3 m distant form trunk. Soil samples were collected at 10 micro and 10 macro habitats at Of and Ah horizons within each plot. Soil ´reaction parameters, pH (H20) and pH (KCl) were measured with a glas electrode. Concentrations of lead, cadmium, zinc, copper, chrome and nickel, extracted in 3N HCl, were analysed by flame atocim absorbtion spectophotometry. The results are represented in Figs 3—18 and listed in Tables 1—2. Hydrogen ion concentration differences between micro and macro habitats indicate a very strong inluence of acid depositions on soil chemistry at some habitats (s. Figs. 3—6). The deposition pattern of heavy meals, above all of lead, shows an increase tendency over an elevation gradient. In subalpine region obtain heavy metals contents extraordinary high level. Lead content for example, can be compared with concentrations of direclty contaminated environments of highway rode sides. Generally exists a topographic coincidence of dieback silver fir stands and habitats with strong influence of acid deposition and high concentration of heavy metals. |