Phenological season onsets in the Czech Republic

Abstract

Phenological season onsets are defined according to the phenological stages onsets in typical plant species
occurring in the Czech Republic. For processing phenological phases were chosen: beginning of flowering
10% of Corylus avellana L., Alnus glutinosa (L.) Gaert. and Galanthus nivalis L. (pre-early spring);
beginning of flowering 10% of Cerasus avium (L.) Moench, Betula pendula Roth. and Acer platanoides L.
(early spring); fully leaved Betula pendula Roth., Acer platanoides L. and Cerasus avium (L.) Moench. (full
spring); beginning of flowering 10% of Tilia cordata Mill., Sambucus nigra L. and Dactylis glomerata L.
(early summer); full ripeness of Sambucus nigra L. and Sorbus aucuparia L. (full summer); leaves colouring
10% of Betula pendula L., Sorbus aucuparia L. and Tilia cordata Mill. (early autumn); leaves fall 100% of
Sambucus nigra L., Sorbus aucuparia L. and Tilia cordata Mill. (end of autumn). The season onsets were
calculated from 40 phenological stations in the Czech Republic within 1991–2010. Phenological season
onsets were executed by GIS methods (Clidata-DEM) into maps. The effect of altitude on the phenological
phase onset and duration of selected phenological period (flowering and ripening of black elder) is described
in phenotermopluviogram at selected stations (Lednice, 155 m a.s.l.; Měděnec 830 m a.s.l.).