Matskási István (szerk.): A Magyar Természettudományi Múzeum évkönyve 93. (Budapest 2001)
Medzihradszky, Zs.: The Holocene sequence of the pollen record from Keszthely-Úsztatómajor, Hungary
Sediment accumulation rate (Fig. I) There is a more or less constant accumulation rate from about 7500 until 2000 years BC. In this period the value of the rate is about 23 years/cm. The sedimentation rate of the upper part of the profile is higher, only c. 7 years/cm. The average for the whole sequence is 20 years/cm. Description of the local pollen assemblage zones (LPAZ) (Fig. 2) LPAZI (-285 cm) - In this zone the arbor and non-arbor pollen ratio of the spectra, apart from small variations, was equal: 75-25%. Of the tree taxa, Pinns had 25%, but because these taxa have a striking pollen production, their role during this period in these forests was undominant. Picea had a continuous 5% value. Among the deciduous trees with their 10-10% values Quercus and Ulmus were the dominating tree species, while Tilia reached only 2-3%. The Fagus pollen curve reaches values about 1%. The ratio of the Poaceae is about 10%, and Artemis7a has relatively high, roughly 10%. The number of the aquatic pollen, e.g. of the rush pollen was very low, but some grains of the Nymphaeaceae refer to open surface and higher water level. LPAZII (285-210 cm ) - The vegetation remained stable until about 8000 BP, when the tree curves raise and the herbaceous pollen percentages are lowered. This zone is a forestation stage, when Quercus, Ulmus and Fagus dominated the forest vegetation, but Tilia was also a characteristic element. Pinus decreased from 25% to 10%. Quercus reached 25%, Tilia about 4-5% and Fagus had in average 10%. This zone was divided to three subzones on the basis of small changes and of the presence or rapid decrease of some taxa. LAPZ Ha (285-255 cm) - At the beginning of this period the values of Quercus and Fagus suddenly increase, while Pinus decreases. There are considerable Poaceae and Cyperaceae peaks, Poaceae had in one spectrum 30% of the total pollen sum, a little later Cyperaceae reached 20%. The AP/NAP ratio changed to 70/30%. Scattered Carpinus pollen are recorded in this phase. LAPZ lib (255-235 cm) -The first pollen of cereals appears. To the end of the zone Quercus decreases a little. Herb pollen curves increase significantly, the value of Poaceae was 10% in average. LAPZ lie (235-210 cm) - The AP/NAP ratio slowly changed in favour of the herbs. The value of Quercus lowered, Ulmus improved a little and Fagus had a relatively high value. A small maximum of Artemisia is apparent. Presence of the cereals is continuous since about 7000 BP. The amount of Sparganium-Typha is almost negligible, but the presence of the reed-grass flora is continuous.
