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Regional maps of rate of change of pollen percentage as a tool for climate change visualization

Walanus A., Nalepka D.

Geological Quarterly

2013

Vol. 57, No. 2

353–-356

Isoline maps of percentage of pollen, obtained for different time horizons through the Holocene, are a typical tool for palaeobotanical studies. In connection with the West Carpathian project the authors have developed the idea of graphically presenting on the map a rate of change of the pollen percentage. Such a map is based on the data from two time horizons. The precision of such a type of map, which shows the %/change/100 yrs, and in which the value can be negative as well as positive, is lower that of a typical isopollen map. However, this type of map gives a direct insight into changes in the plant cover, which are related to climate change.

Integration of Late Glacial and Holocene pollen data from Poland

Walanus A., Nalepka D.

Annales Societatis Geologorum Poloniae

2004

Vol. 74, No 3

285--294

Quaternary palynological data are stored in tables which are typical computer database objects. The individual pollen table, in order to be integrated with other tables using computer-based methods, has to be attributed with (1) geographical coordinates, (2) dates attached to each row (sample) of the table, and (3) taxa names, common to all tables, attached to each column. In this paper, integration of individual lists of palynological taxa is shortly described, and some remarks are given on extracting data for selected time slices. The problem of dating of all pollen spectra, while few radiocarbon dates are available in the profile, is considered. Some mathematical models of age-depth relation are proposed, as well as incorporation of information derived from lithology of the profile. The algorithm of integration (averaging) of pollen percentages on the map of Poland is discussed. The techniques of bootstrap and so-called removed residuals are proposed as tools for assessment of reliability of isopollen lines. A possibility of construction of migration (rate of change) maps is also mentioned. The presented algorithm has been used to obtain hundreds of isopollen maps for the Holocene in the area of Poland .