Matskási István (szerk.): A Magyar Természettudományi Múzeum évkönyve 96. (Budapest 2004)

Molnár, J., Erdei, B. ; Hably, L.: The transport of leaves and fruits - a taphonomical study of leaf litter

and fruits of Acer platanoides differ considerably. The distribution of fruits has a more distorted pattern than that of the leaves which may be attributed to the 'combined' effect of wind and the different average surface and weight of leaves and fruits. Some taxa assemble in a group in all the three diagrams. The reason for this pattern is likely to be the low number of their leaves and fruits in the quadrats. Only the fruits and leaves of Tilia show uniform patterns. Finally, based on our studies the fruits and leaves of a certain taxon - due to the effect of wind transport - may show different behaviour and are expected to have maximum number of specimens often at different distances. Sample plot II In contrast to the samples providing leaves of 36 different species trees growing close to the transections belong to only 23 species (Fig. 4). It is noteworthy that 4 specimens of Ginkgo biloba LINNAEUS, 1771 leaves were also found, although, only two Ginkgo trees can be found in the botanical garden growing more than 300 m to the north-east from our sample plot. Distribution of leaves - The number of leaves in each quadrat sampled in autumn and spring was plotted against distance along the transections (Fig. 15).( The vertical broken lines indicate the location of the certain tree or shrub projected perpendicular on the transection.) The sudden decrease of the number of leaves may be explained by the fact that in a forest leaves are not able to fall freely, and in addition wind velocity is decreased by leafy crowns. However, FERGUSON suggests (1985) that even in a dense forest wind plays an important role in forming the final pattern of leaf litter. Among others the role of wind is supported by the fact that the maximum number of leaves does not coincide in each case with the position of the parent tree projected on the transections. However, it may be due to the asymmetric shape of the leafy crowns, as well and trees have an effect on wind direction beside velocity. Nevertheless, apart from few exceptions our results are well comparable to those of FERGUSON (1985), i.e. the horizontal distance leaves are transported to is generally not more than the height of the parent tree. It is obvious that the life form of a plant is important from the point of view of its fossilization. The leafy crown of high trees is exposed to greater wind velocity, thus their leaves have bigger chance for being transported to longer distance. Therefore leaves or fruits of these trees may be overrepresented in a fossil assemblage as compared to their real quantitative relations in the former vegetation. The 14 m high Quercus robur LINNAEUS, 1753 tree situated in our sample plot (3.5 m