Vízügyi Közlemények, 1998 (80. évfolyam)

3. füzet - Kucsara Mihály: Az erdő csapadékviszonyainak vizsgálata

474 Kucsara Mihály Koloszár J.: Természetes erdei ökoszisztémák és a csapadék. Erdő és Víz munkaértekezlet, Sopron. 1981. Kovács Gy. (mérn.): A felszíni lefolyás általános vizsgálata és az árvizek előrejelzése. Vízügyi Közlemények, 1-2. füzet. 1974. Krutzsch, H. : Die zu forstlichen Zwecken eingerichteten meteorologischen Stationen und die Resultate der Beobachtungen im Jahre 1863. Tharandter forstl. Jahrbuch, 1864. Kucsara M:. Csapadék és lefolyás erdészeti kisvízgyűjtőn. Doktori értekezés, Sopron, 1996. Leonard, R. E.\ Mathematical theory of interception. In: W. E. Sopper and H. W. Hull (Editors), International Symposium on Forest Hydrology. Pergamon Press, Oxford, 1967. Linsley, R. K.-Kohler, M. A.-Paulhus, J. L.\ Applied Hydrology. McGraw-Hill Book Co., New York, 1949. Major P.: Síkvidéki területek talajvízháztartásának vizsgálata. VITUKI témabeszámoló., 1976. Merriam, R. A.: A note on the interception lass equation. Journal of Geophysical Research, 65, 1960. Szabó M. : A csapadékvizsgálat kérdései erdei ökoszisztémákban. Acta Biologica Debrecina, 12, 1975. Szappanos A.: Az akácállomány fontosabb szerkezeti jellemzői. EFE Tudományos Közlemények, 1982. VITUKI: Intercepció vizsgálatok (Helyzetfelmérő tanulmány). Témafelelős: Simonffy Z. Témaszám: 7631(1)21, VITUKI, Budapest, 1978-1979. Weiche, J. \ Niederschlagszurückhaltung durch Wald. Algemeine Forstzeitschrift, 29, 1968. Investigation of the precipitation conditions of forests by Dr. Mihály KUCSARA forest engineer Precipitation water distribution effects of the forest were investigated by the Horton and Merriam formulas (Figure /.). Three interception experimental plots were constructed (Figures 2. and 3.). Data were collected in two periods: 1986-1989 and 1993—1995. Changes of the tree stock of the experimental plots are illustrated in Figure 4. The relationship between precipitation and interception was described by the Merriam formulas (Eqs. 7—9) and by the Weich type functions (Eqs. 10-12). The Merriam and Weich functions fitted to the 10 year observation data (to the interval averages) of the three experimental plot are shown in Figure 6. Stemflow is an important part of the precipitation water and should be separated from the water falling through the canopy (called throughfall). This is because stemflow, flowing along the branches and trunks of the trees until it reaches the ground, will fully infiltrate into the soil along the roots of the tree. On the other hand throughfall across the canopy will be subject to further losses, by the moistening of and storage in the lief-litter. In the case of heavier storm events stemflow, however, will result in better soaking of the soil around the trees. Three formulas (Equations 13—14) was developed by the author for describing stemflow in function of the magnitude of the rainfall event. Figure 7 illustrates that stemflow is more intensive in beech stocks than in other woods and starts at smaller rainfalls. Therefore the growth rate of beech is higher than that of the spruce. Comparing stocks of similar age of beech and spruce it was found that stemflow from rainfalls of 20-30 mm was three times higher in beech than in spruce. In Table II. the author shows the distribution of rainfall, as calculated by the Merriam formula, among the various trees. The calculated interception of young beech was 29.0% in the average of five years. Leaf-litter was reached annually by 366.5 mm precipitation water in average, 15.7% of which arrived as stemflow. This is 11.2% of the total precipitation onto the area. The annual interception of young spruce was 38.0% in the average of five years. There was substantial difference (11.9%) between the lowest (31.1%) and the highest (43.0%) annual intercep-