Heat requirement for the onset of the Olea europaea L. pollen season in several sites in Andalusia and the effect of the expected future climate change

Abstract

Olives are one of the largest crops in the Mediterranean region, especially in Andalusia, in southern Spain. A thermal model has been developed for forecasting the start of the olive tree pollen season at five localities in Andalusia: Cordoba, Priego, Jaen, Granada and Malaga using airborne pollen and meteorological data from 1982 to 2001. Threshold temperatures varied between 5 degrees C and 12.5 degrees C depending on bio-geographical characteristics. The external validity of the results was tested using the data for the year 2002 as an independent variable and it confirmed the model's accuracy with only a few days difference from predicted values. All the localities had increasingly earlier start dates during the study period. This could confirm that olive flower phenology can be considered as a sensitive indicator of the effects of climate fluctuations in the Mediterranean area. The theoretical impact of the predicted climatic warming on the olive's flowering phenology at the end of the century is also proposed by applying Regional Climate Model data. A general advance, from 1 to 3 weeks could be expected, although this advance will be more pronounced in mid-altitude inland areas.

Evaluation of olive flowering at low latitude sites in Argentina using a chilling requirement model

“…In this regard, Galán et al (2005) found different Tb values for accumulating thermal time until flowering in olive depending on the values of average air temperatures at different sites in Andalusia (Spain). Aguilera et al (2014) also reported over a wide latitudinal gradient from central Italy (43°N) to southern Tunisia (33°N) that more southerly olive populations had lower thermal time requirements than those in the north.…”

Influence of meteorological parameters onOleaflowering date and airborne pollen concentration in four regions of Portugal

“…The development of site-specific forecasting models is important because plants are adapted to the surrounding environment, and differences in the development activity are observed even within the same species when located in diverse conditions (O'Neil, 1999;Galán et al 2005 Grana, 2006;45: 115-121 The aim of this work was to develop a predictive model, adjusted to Portuguese climatic conditions, for the total annual Olea airborne pollen concentration, the onset of the MPS and the peak pollen concentration dates.…”

Aerobiology in the International Journal of Biometeorology, 1957–2017

“…10/year). Following this article are those by Galán et al (2005) (114 citations, approx. 10/year), Sofiev et al (2006) (111 citations, approx.…”

“…Other research on the impacts of climate change on pollen season characteristics has subsequently been published in IJB, including Galán et al (2005), Frei and Gassner (2008), Newnham et al (2013) and Sofia et al (2017), to name but a few. As noteworthy as the IJB contribution to this area of research has been, it has not been the sole domain of such work.…”