Department of Botany, Ecology and Plant Physiology, Agrifood Campus of International Excellence CeiA3, University of Cordoba, Rabbinates Campus, Celestino Mutis Building, E-14071 Córdoba, Spain; Andalusian Inter-University Institute for Earth System IISTA, University of Cordoba, Spain.
Sci Total Environ. 2023 Nov 1;897:165400. doi: 10.1016/j.scitotenv.2023.165400. Epub 2023 Jul 7.
Climate change is disrupting phenology and interaction patterns of natural ecosystems, but also human activities that modify land-uses have a direct impact, especially on species distribution and loss of biodiversity. The objective of this study is to evaluate the impact of climate and land-use changes on phenology and airborne pollen spectrum in a Mediterranean natural area, dominated by Quercus Forest and 'dehesa', in the South of the Iberian Peninsula. 61 different pollen types were identified over a 23-year period (1998-2020), mainly from trees and shrubs, such as Quercus, Olea, Pinus or Pistacia, and from herbaceous plants, such as Poaceae, Plantago, Urticaceae or Rumex. A comparison of pollen data from the first years of the study (1998-2002) up recent years (2016-2020), showed a substantial decrease in the relative abundance of pollen from autochthonous species associated with natural areas, such as Quercus or Plantago. However, the relative abundance of the pollen from cultivated ones such as Olea and Pinus, which is used for reforestation has increased. Regarding flowering phenology trends, our analyses revealed variations between -1.5 and 1.5 days per year. Taxa showing an advance phenology were Olea, Poaceae and Urticaceae, whereas Quercus, Pinus, Plantago, Pistacia or Cyperaceae experienced delayed pollination. Meteorological trends in the area generally resulted in an increase in both minimum and maximum temperatures, along with a decrease in precipitations. Changes in pollen concentration and phenology were correlated with changes in air temperatures and precipitation, although the positive or negative influence varied for each pollen type. The results suggest that climate change together with those motivated by land cover changes lead by human activities are having an impact on the phenology and pollen concentration, with the related consequences on pollination and therefore biodiversity more concerning in threatened areas as the Mediterranean Basin.
气候变化正在扰乱自然生态系统的物候和相互作用模式，但人类改变土地利用的活动也会产生直接影响，特别是对物种分布和生物多样性丧失的影响。本研究的目的是评估气候和土地利用变化对伊比利亚半岛南部地中海自然区域物候和空气花粉谱的影响。在 23 年的时间里（1998-2020 年），共鉴定出 61 种不同的花粉类型，主要来自树木和灌木，如栎属、油橄榄、松树或黄连木，以及草本植物，如禾本科、车前草、荨麻科或酸模属。对研究前几年（1998-2002 年）和最近几年（2016-2020 年）的花粉数据进行比较后发现，与自然区域相关的本地物种的花粉相对丰度大幅减少，如栎属或车前草。然而，用于重新造林的栽培物种如油橄榄和松树的花粉相对丰度有所增加。关于开花物候趋势，我们的分析显示每年有-1.5 到 1.5 天的变化。表现出物候提前的类群是油橄榄、禾本科和荨麻科，而栎属、松树、车前草、黄连木或莎草科的授粉则延迟。该地区的气象趋势通常导致最低和最高温度的增加，同时降水量减少。花粉浓度和物候的变化与空气温度和降水的变化相关，尽管每种花粉类型的影响是积极的还是消极的有所不同。结果表明，气候变化以及人类活动引起的土地覆盖变化正在对物候和花粉浓度产生影响，对授粉和生物多样性产生相关影响，在像地中海盆地这样的受威胁地区更为关注。
