title: Environmental behaviour of airborne Amaranthaceae pollen in the southern part of the Iberian Peninsula, and its role in future climate scenarios.
abstract: The Amaranthaceae family includes a number of species which, through a series of specific adaptations, thrive in salty soils, arid environments and altered human settlements. Their ability to tolerate high temperatures favours summer flowering, giving rise to the widespread involvement of Amaranthaceae pollen grains in summer allergies, both in Mediterranean Europe and in areas with arid climates. This study analysed a 21-year set of historical airborne Amaranthaceae pollen records for an area located in the southern part of the Iberian Peninsula, in order to chart species' environmental reaction to changing climate conditions which occurred in the last decades. Airborne pollen data were collected from January 1991 to December 2011 using a Hirst-type volumetric impact sampler. Results showed that Amaranthaceae pollen remained in the atmosphere for over 6 months along the year, from early spring until early autumn. The annual Pollen Index ranged from barely 200 grains to almost 2000 grains, and was strongly influenced by rainfall during the flowering period, which prompted the development of new individuals and thus an increase in pollen production. A trend was noted towards increasingly early pollen peak dates; peaks were recorded in August-September in years with summer rainfall, but as early as May-June in years when over 50% of annual rainfall was recorded in the months prior to flowering. The gradual decline in the annual Pollen Index over later years is attributable not only to growing urbanisation of the area but also to a change in rainfall distribution pattern. High maximum temperatures in spring were also directly related to the peak date and the Pollen Index. This ability to adapt to changeable and occasionally stressful and restrictive, environmental conditions places Amaranthaceae at a competitive advantage with respect to other species sharing the same ecological niche. An increased presence of Amaranthaceae is likely to have a greater impact on future scenarios for pollen allergy diseases associated with climate change.
authors.affiliation: Dept. of Botany, Faculty of Pharmacy, Campus de Cartuja, University of Granada, Spain. Electronic address: palomacg@ugr.es.
authors.forename: Paloma
authors.initials: P
authors.lastname: Cariñanos
authors.affiliation: Dept. of Plant Biology, Plant Physiology and Ecology, Campus de Rabanales, Edif. Celestino Mutis, University of Córdoba, Spain.
authors.forename: Purificación
authors.initials: P
authors.lastname: Alcázar
authors.affiliation: Dept. of Plant Biology, Plant Physiology and Ecology, Campus de Rabanales, Edif. Celestino Mutis, University of Córdoba, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Galán
authors.affiliation: Dept. of Plant Biology, Plant Physiology and Ecology, Campus de Rabanales, Edif. Celestino Mutis, University of Córdoba, Spain.
authors.forename: Eugenio
authors.initials: E
authors.lastname: Domínguez
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000032:analysis* / Q000706:statistics & numerical data; D000485:Allergens / Q000032:analysis; D027703:Amaranthaceae; D001272:Atmosphere / Q000737:chemistry; D002980:Climate; D003889:Desert Climate; D004784:Environmental Monitoring; D011058:Pollen; D012621:Seasons; D013030:Spain
chemical_list: D000393:Air Pollutants; D000485:Allergens
keywords: Aerobiology; Airborne pollen; Amaranthaceae; Climate change; Pollen allergy