This book covers the landscape, geography and environment of the Sierra Nevada in Spain. The Sierra Nevada hosted the last glaciers in southern Europe. Today, it is one of the most important centers of plant diversity in the western Mediterranean and one of the most outstanding in Europe. This massif has ideal conditions to analyze past environments as well as the effects of global change on ecosystems. This can be seen in the large number of projects that are being conducted within the umbrella of the Sierra Nevada Global Change Observatory. This book summarizes all the scientific knowledge available about this massif, from the geomorphological and ecological perspectives to the recent spatial adaptive management and Open Science initiatives. Focusing on the very sensitive mountain environment of Sierra Nevada, the book intends to be a reference for many people interested in mountain processes. The audience would include scientists from all disciplines, but it would also target on an audience beyond the academia (territorial managers, environmentalists, mountaineers, politicians, technicians, etc.).
Land abandonment is a major global change driver in the Mediterranean region, where anthropic activity has played an important role in shaping landscape configuration. Understanding the woodland expansion towards abandoned croplands is critical to develop effective management strategies. In this study, we analyze the colonization pattern of abandoned croplands by Quercus pyrenaica in the Sierra Nevada mountain range (southern Spain). We aimed to assess differences among populations within the rear edge of the Q. pyrenaica distribution. For this purpose, we charac-terized (i) the colonization pattern of Q. pyrenaica, (ii) the structure of the seed source (surrounding forests), and (iii) the abundance of the main seed disperser (Eurasian jay, Garrulus glandarius). The study was conducted in five abandoned croplands located in two representative populations of Q. pyrenaica located on contrasting slopes. Vegetation plots within three habitat types (mature forest, edge-forest and abandoned cropland) were established to compute the abundance of oak juveniles. The abundance of European jay was determined using data of bird censuses (covering 7 years). Our results indicate that a natural recolonization of abandoned croplands by Q. pyrenaica is occurring in the rear edge of the distribution of this oak species. Oak juvenile abundance varied between study sites. Neither the surrounding-forest structure nor the abundance of jays varied significantly between study sites. The differences in the recolonization patterns seem to be related to differences in the previous-and post-abandonment management. ; This research was partially funded by the LIFE-ADAPTAMED (LIFE14CCA/ES/000612) project, by MIGRAME Project (Excellence Research Group Programme of the Andalusian Government (RNM 6734), and by eLTER H2020 project.
Global change triggers shifts in forest composition, with warming and aridification being particularly threatening for the populations located at the rear edge of the species distributions. This is the case of Scots pine (Pinus sylvestris) in the Mediterranean Basin where uncertainties in relation to its dynamics under these changing scenarios are still high. We analysed the relative effect of climate on the recruitment patterns of Scots pine and its interactions with local biotic and abiotic variables at different spatial scales. Number of seedlings and saplings was surveyed, and their annual shoot growth measured in 96 plots located across altitudinal gradients in three different regions in the Iberian Peninsula. We found a significant influence of climate on demography and performance of recruits, with a non-linear effect of temperature on the presence of juveniles, and a positive effect of precipitation on their survival. Abundance of juveniles of P. sylvestris that underwent their first summer drought was skewed towards higher altitudes than the altitudinal mean range of the conspecific adults and the optimum elevation for seedlings¿ emergence. At local level, light availability did not influence juveniles¿ density, but it enhanced their growth. Biotic interactions were found between juveniles and the herb cover (competition) and between the number of newly emerged seedlings and shrubs (facilitation). Results also highlighted the indirect effect that climate exerts over the local factors, modulating the interactions with the pre-existing vegetation that were more evident at more stressful sites. This multiscale approach improves our understanding of the dynamics of these marginal populations and some management criteria can be inferred to boost their conservation under the current global warming. ; Funding was provided by the Spanish Ministry for Innovation and Science with the grant Consolider-Montes (CSD2008_00040), and the European Union with the projects BACCARA (CE: FP7-226299, 7FP) and FunDivEUROPE (CE: FP7-ENV-2010. 265171). ; Peer Reviewed
Climate change is expected to alter the geographic distribution of many plant species worldwide. However, there is still no clear evidence showing a generalised direction and magnitude of these distribution shifts. Here, we have surveyed, in nine mountainous regions in Spain, an array of tree species along entire elevational ranges, as surrogates of their global climatic ranges, to test for elevational shifts towards cooler locations. We analysed the distribution recruitment patterns of five dominant tree species, recording the abundance and measuring the primary growth of juveniles in 306 plots. Three of the species have a temperate-boreal distribution with populations at their southern edge in the Mediterranean mountain ranges: Pinus sylvestris, Pinus uncinata and Fagus sylvatica; and the other two species have a Mediterranean distribution: Quercus ilex and Pinus nigra. Despite the contrasting phylogenies and biogeographies, we identified a similar pattern in recruitment abundance across species, with an asymmetric distribution of juveniles (more recruits in the middle-upper elevation of their range), but higher annual growths at lower elevations. This survival-growth trade-off at the early recruitment stage may potentially counterbalance at population level the negative effect of global warming on recruit survival at the lower edge of species ranges. These findings suggest a demographic stabilisation process at the early recruitment stage of these tree species, and highlight the importance of considering the different demographic stages across the whole climatic range to understand the effects that climate change may exert on species distributions and population dynamics. ; RB was funded by a Marie Curie IEF fellowship (FP7-PEOPLE-2011-IEF). Funding also was provided by the Spanish Ministry for Innovation and Science with the grant Consolider-Montes (CSD2008_00040), VULGLO (CGL2010 22180 C03 03), MOUNTAINS (CGL-2012-38427), the Community of Madrid grant REMEDINAL 2 (CM S2009 AMB 1783) and the European Union with the projects BACCARA (CE: FP7-226299, 7FP) and FunDivEUROPE (CE: FP7-ENV-2010. 265171).
