Naslov
Trends of the phenological phases and growing degree days for olive trees in Croatia

Autori
Vučetić, Marko ; Vučetić, Višnjica

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Proceedings of Abstracts PHENOLOGY 2018 One planet, two hemispheres, many regions / Keatley, Marie R. - Melbourne : International Society of Biometeorology, 2018, 44-44

Skup
Phenology 2018: One planet, two hemispheres, many regions

Mjesto i datum
Melbourne, Australija, 23.09.2018. - 28.09.2018

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
olive, phenological phases, GDD, trend, climate change, Croatia

Sažetak
Weather conditions in the recent years less and less follow known annual and seasonal cycles and more and more extreme weather events endanger agricultural production. The Adriatic coast with the islands is the most vulnerable area in Croatia on the climate change. The olive cultivation and oil production are particularly economically important for this area. How much olive marks Croatian coastline shows that the Mediterranean climate is also referred as the olive climate. The aim is to determine the trends in phenological phases of olive and the changes of heat accumulation from one phase to next using growing degree days (GDD) with the temperature thresholds of 7°C in the period 1986-2015 related to normal 1961-1990. Five phenophases from seven stations have been analyzed in the period 1961-2015. The beginning, full and end of flowering are a week earlier in the mid-Adriatic than northern. First ripe fruits are usually by the middle of October, while the picking is in the first ten days in November. Linear trend analysis shows earlier flowering by 2 days/decade in northern Adriatic, while in mid-Adriatic by 3 days/decade. Earlier olive ripe 3 days/decade is observed in mid-Adriatic, while earlier picking (2-4 days/decade) is not just a result of weather conditions, but it depends on market demand for certain oil quality. The spring phenophases require in average around 750-1000°C growing-degree days, 3100-3400°C for the first ripening and 3200-3600°C for picking over last 30 years. GDDs for flowering are similar for both periods but GDDs for the autumn phenophases increase by 150-300°C in the recent period. Using the phenological data (1961-2015) and GDD for each phenopahes (1877-2015) for the mid-Adriatic station of Hvar, the olive phenophases has been reconstructed in the past. The trends in estimated autumn phenophases (21-27 days/century) are faster than for flowering (5-6 days/century).

Izvorni jezik
Engleski

Znanstvena područja
Geofizika

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