Long-term trends of atmospheric Quercus pollen recorded for 25 years (1995–2019) in southern Spain (Cordoba city, Andalusia region) have been studied to determine the influence of climate fluctuations and other anthropogenic factors on Mediterranean oak vegetation areas. Atmospheric pollen analysis revealed different changes on reproductive Quercus phenology through the study period. Pollination intensity showed an average cumulated value of the Main Pollen Season Integral of 12,832 Pollen * day/m³, with a high variability among years (±SD 8,048) and a significant rising trend of 771 pollen grains per year, being stronger in recent years (2014–2019). It was remarkable the high quantity of Quercus pollen grains detected out of the Main Pollen Season (703 Pollen * day/m³ ± SD 431), also increasing in recent years.

Regarding Quercus phenology, results indicated as the main Quercus species in the area, Quercus ilex subsp. ballota (holm oak), Q. coccifera, Q. faginea and Q. suber, presented a gradually pollination during spring (from mid-March to early June), although a lengthening of the pollination season is observed in recent years. This phenomenon could be explained by the progressive delay in the pollination of Q. suber. Regarding climate factors, a decrease in rainfall, especially during winter and autumn was recorded, along with colder winters but warmer springs, summers, and autumns. These changes were significantly correlated with pollination timing and intensity. The climate parameters most affecting were those related to temperature and sunshine. However, the total annual pollen showed a significant negative correlation with the annual recorded rainfall. Results show that recent climatic change, among other factors, are leading to changes in the timing and intensity of the Quercus pollen season in the Mediterranean area.

研究了西班牙南部（安达卢西亚地区科尔多瓦市）25 年（1995-2019 年）记录的大气栎属花粉的长期趋势，以确定气候波动和其他人为因素对地中海橡树植被区的影响。大气花粉分析揭示了整个研究期间栎属植物物候的不同变化。授粉强度显示，主花粉季积分平均累积值为12,832花粉*天/m ³，年际变异性较大（±SD 8,048），每年771粒花粉粒呈显着上升趋势，近年来增强（2014-2019 年）。栎属植物的数量非常多在主要花粉季节检测到的花粉粒 (703 花粉 * 天/m ³  ± SD 431)，近年来也在增加。

关于栎属物候学，结果表明该地区的主要栎属物种Quercus ilex subsp。ballota（圣栎）、Q. coccifera、Q. faginea和Q. suber在春季（3 月中旬至 6 月初）呈现逐渐授粉，尽管近年来观察到授粉季节延长。这种现象可以用Q. suber授粉的逐渐延迟来解释. 在气候因素方面，降雨量减少，尤其是在冬季和秋季，同时冬季较冷，但春季、夏季和秋季较暖和。这些变化与授粉时间和强度显着相关。影响最大的气候参数是与温度和阳光有关的参数。然而，年花粉总量与年记录降雨量呈显着负相关。结果表明，近期的气候变化等因素导致地中海地区栎属花粉季节的时间和强度发生变化。