The influence of climate changes in Platanus spp. pollination in Spain and Italy

Figures & data

Figure 1 Location of the studied areas in Europe.

Table I. Slopes and significance levels of the mean temperature year and month trends during the studied period.

Period	Slope (R^2 value)
	Vigo	Santiago	Perugia	Torino
Year	−0.262∗∗∗ (0.636)	0.055∗ (0.333)	0.078∗∗∗ (0.582)	0.156∗∗∗ (0.934)
January	−0.214 (0.322)	0.035 (0.028)	−0.004 (0.001)	0.072∗∗ (0.187)
February	−0.089 (0.142)	0.097 (0.068)	0.111∗∗∗ (0.321)	0.191∗∗∗ (0.598)
March	−0.185∗∗ (0.491)	0.119∗ (0.055)	0.119∗∗∗ (0.303)	0.184∗∗∗ (0.640)
April	−0.399∗∗ (0.450)	0.029 (0.080)	0.001 (0.000)	0.091∗∗∗ (0.546)
May	−0.217∗∗∗ (0.724)	0.080 (0.066)	0.114∗∗∗ (0.608)	0.195∗∗∗ (0.839)
June	−0.507∗∗∗ (0.823)	0.047 (0.061)	0.212∗∗∗ (0.555)	0.205∗∗∗ (0.662)
∗ – p<0.1; ∗∗ – p<0.05; ∗∗∗ – p<0.001.

Figure 2 Length average of thePlatanus pollen season in the studied years. Mean peak value date marked with a point.

Table II. Slopes and significance levels of the trends of the parameters that define the Platanus pollen season during the studied years: total annual pollen, start and final date of the pollen season, length of the pollen season, peak value and its date, and skewness and kurtosis values.

Features	Slope (R^2 value)
	Vigo	Santiago	Perugia	Torino
Total pollen	6.400 (0.013)	4.840 (0.001)	1.350 (0.030)	−47.570 (0.098)
Start date	0.232 (0.025)	0.850∗∗ (0.387)	−0.660∗∗∗ (0.515)	−1.212∗∗∗ (0.622)
Final date	−0.704 (0.096)	0.670∗ (0.328)	−0.646∗∗∗ (0.437)	−0.692∗∗∗ (0.324)
Length pollen season	−0.936∗∗ (0.542)	−0.173 (0.017)	0.401 (0.075)	0.513∗∗∗ (0.375)
Peak value	9.500 (0.240)	−2.426 (0.009)	−0.390 (0.060)	−21.018∗∗∗ (0.327)
Date peak	−0.067 (0.001)	1.010∗ (0.358)	−0.406∗∗ (0.182)	−1.019∗∗∗ (0.502)
Skewness	0.088∗ (0.421)	−0.042∗ (0.276)	−0.048∗∗∗ (0.460)	−0.031 (0.098)
Kurtosis	0.257 (0.276)	−0.164∗ 0.291)	−0.226∗∗∗ (0.325)	0.063 (0.052)
∗ – p<0.1; ∗∗ – p<0.05; ∗∗∗ – p<0.001.

Figure 3 Correlation between starting dates of thePlatanus pollen season and mean temperature average value of the month in which the release of the pollen takes place [y = −3.9626x+116.5; R² = 0.6332; p<0.000].

Figure 4 Average of daily pollen counts in the studied period(area) and its distribution in the coldest (line) and the hottest year (pointed line).

Figure 5 Skewness, kurtosis and total pollen values during the coldest and hottest year.