Average rate of phenological changes in Poland according to climatic changes – evaluation and mapping

Abstract. The main objective of this study was evaluation and mapping of an average rate of phenological changes for example special plant s indicators as a result of climatic changes in Poland.

Multi-year analysis clearly showed a tendency to earlier onset of spring events. The average advance of flowering/leafing was −1.4 days/decade and −2.4 days/1°C. Whereas the response of autumn phenophases was ambiguous. Phenological and climate data come from archives of the Institute of Meteorology and Water Management.

Analysis covered the period of 1951–1992. The relation between temperature and date of phenophases was described with Pearson's linear regression model. Statistical significance of the model parameters was checked with Student's t-test at the following levels: 0.05, 0.01, and 0.001.

The results were visualised on maps. ArcGIS 9.2 Geostatistical Analyst was used to examine the data and create prediction maps. Numerous tests were performed in order to find an appropriate method of spatial interpolation. Finally kriging was chosen as the most precise.