Long-term Changes of Vegetation Season in Context of Spring Barley Phenology in South Moravia
Keywords:phenological phases, active temperature, climate change, barley, harvest
The paper deals with the active sum of daily average air temperature above 5, 10, and 15 °C, and with the length of the vegetation season which is given by values of the daily average values of air temperature exceeding the given threshold (5, 10, 15 °C). The average values of four long-term periods (1931–1960, 1961–1990, 2021–2050, and 2071–2100) were compared to one another. A gradual increase of all the above mentioned characteristics was found. The area of interest involves several localities in south Moravia (the Czech Republic). These fi ndings were confronted with a long-term (1931–2012) analysis of spring barley’s phenological phases and with the date of sowing and the beginning of harvest. A prolongation of the interval between sowing and harvest was found; this was probably caused by agronomy machinery advancement. A prolongation of the interval between sowing and emergence and between heading and harvest, and a shortening of the interval between emergence and heading was also proved. A trend analysis of spring barley phenophases during 1961–1990 did not prove almost any signifi cant changes, except for a 12-day delay of the beginning of the harvest day, which was probably caused by a more effective mechanization.