• Energy Research

The 11th Conference of the Spanish Association of Terrestrial Ecology, held in Pamplona, Spain, on 6-10 May 2013, included a symposium on alpine ecological research in the Iberian Peninsula. This session offered an excellent opportunity to assess the state and progress of alpine ecology in this region, identify knowledge gaps, and discuss further directions for research. Iberian alpine ecosystems are biodiversity hotspots and have traditionally contributed to sustaining rural livelihoods. Today, these ecosystems are subjected to large changes in land uses, including land abandonment, and are affected by climate change. This article reviews the current state of Iberian alpine ecology and proposes a research agenda. Alpine ecology in the Iberian Peninsula is a growing field of research. The need for larger spatial and temporal scales in research and monitoring, along with the integration of socioecological aspects, is a critical issue for understanding the major drivers of change in the alpine ecosystems of the Iberian Peninsula. The implementation of effective mitigation strategies aimed at reducing the impact of the pressing environmental and socioeconomic problems of Iberian mountain areas can only be accomplished through a multidisciplinary and integrative approach.

Over the last decades, global changes have altered the structure and properties of natural and semi-natural mountain grasslands. Those changes have contributed to grassland loss mainly through colonization by woody species at low elevations, and increases in biomass and greenness at high elevations. Nevertheless, the interactions between agropastoral components; i.e., ecological (grassland, environmental, and geolocation properties), social, and economic components, and their effects on the grasslands are still poorly understood. We estimated the vulnerability of dense grasslands in the Central Pyrenees, Spain, based on the connectivity loss (CL) among grassland patches that has occurred between the 1980s and the 2000s, as a result of i) an increase in biomass and greenness (CL-IBG), ii) woody encroachment (CL-WE), or iii) a decrease in biomass and greenness (CL-DBG). The environmental and grassland components of the agropastoral system were associated with the three processes, especially CL-IBG and CL-WE, in relation with the succession of vegetation toward climax communities, fostered by land abandonment and exacerbated by climate warming. CL-IBG occurred in pasture units that had a high proportion of dense grasslands and low current livestock pressure. CL-WE was most strongly associated with pasture units that had a high proportion of woody habitat and a large reduction in sheep and goat pressure between the 1930s and the 2000s. The economic component was correlated with the CL-WE and the CL-DBG; specifically, expensive pastures were the most productive and could maintain the highest rates of livestock grazing, which slowed down woody encroachment, but caused grassland degradation and DBG. In addition, CL-DBG was associated with geolocation of grasslands, mainly because livestock tend to graze closer to passable roads and buildings, where they cause grassland degradation. To properly manage the grasslands, an integrated management plan must be developed that includes an understanding of all components of the agropastoral system and takes into account all changes that have occurred in dense mountain grasslands. Addressing the problems individually risks the improvement of some grasslands and the deterioration of others.

Las observaciones sobre el cambio medioambiental realizadas por usuarios locales pueden ser una importante fuente de información sobre las características medioambientales del pasado y del presente para complementar los estudios científicos y el monitoreo. En este estudio cualitativo documentamos observaciones sobre el cambio medioambiental realizadas por 27 ganaderos en los dos valles más occidentales de los Pirineos centro occidentales españoles. Resumen cambios climáticos relativos a la disminución del caudal de las fuentes de montaña y al aumento de la cubierta vegetal de matorrales y arbolado en las montañas. Las explicaciones sobre el aumento de arbolado difieren en los dos valles; sin embargo la mayoría de los ganaderos de ambos pueblos pensaban que la falta de presencia humana en las montañas contribuye a la invasión del matorral. Las observaciones de los ganaderos sobre los cambios medioambientales sugieren la necesidad de investigaciones adicionales sobre los cambios climáticos y de vegetación en los Pirineos y evidencian las potenciales contribuciones del conocimiento local de los ganaderos para el monitoreo medioambiental, la investigación y la gestión.