Changes in the Mediterranean pine forest: pollination patterns and annual trends of airborne pollen
In some areas, forests are being affected in diverse aspects such as structure, composition and biodiversity showing an increase or a decrease in the growth rates. Pinus is one of the most dominant genera in the forests of the Northern Hemisphere. This study analyzes the pine pollination patterns in 30 locations of Spain with an average of 21-year dataset. The aim is to evaluate possible changes in flowering intensity as well as in annual pollen production trends, according to the airborne pollen patterns. Annual Pollen Indices show three threshold values: (1) over 4000 grains per year in Catalonia, the Central System Mountains and Ourense (Galicia), (2) between 4000 and 1000 grains in central-south Spain and in the Balearic Islands, and (3) under 1000 in eastern Spain, Cartagena and the Canary Islands. Airborne pollen patterns were also influenced by Pinus species: The species located in the littoral and low land areas pollinated in the first pollination phase, from February to April, and the mountain pine species did in the second one, from April to June. The statistical analyses reveal increasing significant trends in 12 sites and significant decreasing trends in two. The Pinus flowering intensity is showing an earlier start and a delay in the end of the pollination period, thus a longer period of pollen in the air. This study suggests that the aerobiological monitoring is an interesting bio-indicator of changes happening in Pinus landscapes, and therefore explains the vulnerability of this genus in Spain.
KeywordsPinus pollen Environment and climate change Flowering intensity Annual trends Pollination patterns
The authors wish to thank different projects and entities for financing this study: COST ES0603 EUPOL; Laboratorios LETI S.A.; Proyecto EOLO-PAT; European Commission for “ENV4-CT98-0755”; Spanish Ministry of Science and Technology I+D+I for “CGL2009-11205,” “CGL2012-39523-C02-01/CLI,” “MTM2015 67802-P,” “FENOMED CGL2014-54731-R,” and FEDER “A way to build Europe,” and CONSOLIDER CSD 2007_00067 GRACCIE; also the Andalusian Government for “P10-RNM-5958,” the Extremadura Government for “PRI BS10008,” the Catalan Government AGAUR for “2009SGR1102” and “2014SGR1274” and the Health Department of the Castilla y León Government, RACYL. This work is contributing to the ICTA “Unit of Excellence” (MinECo, MDM2015-0552).
- Allué, J. L. (1990). Atlas fitoclimático de España [Phytoclimatic Atlas of Spain]. Madrid: INIA.Google Scholar
- Cariñanos, P., De la Guardia, C., Algarra, J. A., De Linares, C., & Irurita, J. M. (2013). The pollen counts as bioindicator of meteorological trends and tool for assessing the status of endangered species: The case of Artemisia in Sierra Nevada (Spain). Climatic Change, 119, 1–15.CrossRefGoogle Scholar
- Castroviejo, S., Aedo, C., Cirujano, S., Laínz, M., Montserrat, P., Morales, R., et al. (Eds.). (1993). Flora ibérica 1. Madrid: Real Jardín Botánico, CSIC.Google Scholar
- DGCN, IFN3. (2007). Tercer Inventario Forestal Nacional, IFN3 (1997–2007) [Third National Forest Inventory, IFN3 (1997–2007)]. Madrid: Ministerio de Medio Ambiente. http://www.magrama.gob.es/es/biodiversidad/servicios/banco-datos-naturaleza/informacion-disponible/ifn3.aspx. Accessed November 9, 2016.
- FAO. (2011). State of the world’s forests. Rome: Food and Agriculture Organization of the United Nations.Google Scholar
- FAO. (2012). Forest management and climate change: A literature review. Rome: Food and Agriculture Organization of the United Nations.Google Scholar
- Galán, C., Cariñanos, P., Alcázar, P., & Domínguez, E. (2007). Manual de Calidad y Gestión de la Red Española de Aerobiología [Quality manual and management Spanish aerobiology network]. Spain: Servicio de Publicaciones de la Universidad de Córdoba.Google Scholar
- Gobierno de Canarias. (2007) Programa de desarrollo rural de Canarias. FEADER (2007) [Rural Development Programme de Canarias. FEADER 2007]. Canarias: Gobierno de Canarias. http://www.pdrcanarias.org. Accessed November 9, 2016.
- Lenoir, J., Gégout, J. C., Guisan, A., Vittoz, P., Wohlgemuth, T., Zimmermann, N. E., et al. (2010). Going against the flow: Potential mechanisms for unexpected downslope range shifts in a warming climate. Ecography, 33(2), 295–303.Google Scholar
- Navascués, M., Vendramin, G. G., & Emerson, B. C. (2007). The effect of altitude on the pattern of gene flow in the endemic canary island pine, Pinus canariensis. Silvae Genetica, 57, 357–363.Google Scholar
- Pérez Badia, R., Rapp, A., Morales, C., Sardinero, S., Galán, C., & García-Mozo, H. (2010). Pollen spectrum and risk of pollen allergy in central Spain. Annals of Agricultural and Environmental Medicine, 17, 139–151.Google Scholar
- R Development Core Team. (2007). R: A language and environment for statistical computing. Vienna: R Foundation for Statistical Computing.Google Scholar
- Theil, H. (1950). A rank-invariant method of linear and polynomial regression analysis. I, II, III. Proceedings of the Knoniklijke Nederlandse Academie van Wetenschappen, 53, 386–392.Google Scholar
- Tormo-Molina, R., Gonzalo-Garijo, M. A., Silva-Palacios, I., & Muñoz-Rodríguez, A. F. (2010). General trends in airborne pollen production and pollination periods at a Mediterranean site (Badajoz, Southwest Spain). Journal of Investigational Allergology and Clinical Immunology, 20(7), 567–574.Google Scholar