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Ecología del bosque mediterráneo en un mundo cambiante
In: Naturaleza y parques nacionales
In: Serie técnica
Recruitment patterns of four tree species along elevation gradients in Mediterranean mountains: not only climate matters
Evidence of tree regeneration failure of some species in the Iberian Peninsula forests warns us about the impact that the global change may exert on the preservation of Mediterranean forests, such as we know them. Predictions agree about an exacerbation of the summer drought there, acknowledged as the main limiting factor for the recruits' survival. On the other hand, many studies have also proved the relevant role that local heterogeneity has over the spatial distribution of forest species recruitment by providing safe sites. Therefore, to unravel how climate interacts with local factors over juveniles' performance seems crucial for the design of successful management strategies that allow facing the global warming. Here, we surveyed the natural recruitment of four dominant tree species in seven mountainous regions in the Iberian Peninsula, along entire elevational ranges as surrogates of their climatic ranges. Two of them have alpine and temperate distributions with populations at their rear edge in the Spanish mountains: Fagus sylvatica and Pinus uncinata; and the other two have a genuine Mediterranean distribution: Quercus ilex and Pinus nigra. Our main goal was to analyze for each species the effect of climate, local factors (i.e. light availability, stand structure and ground cover) and the interactions among them to identify the main drivers leading the regeneration process, assessed in terms of presence, abundance and mean annual growth of juveniles. The results showed different environmental factors determining the recruitment patterns of each species. Nevertheless, they highlighted the pervasive role exerted by both climate and fine scale factors, particularly the co-occurring vegetation on recruits' abundance, and the light availability on their growth. Moreover, we found some interactions among annual mean temperature and local factors, suggesting that climate and local heterogeneity act hierarchically, i.e. the local conditions may mitigate or exacerbate the impact of climate on juveniles. These results advocate for further research to increase our knowledge on the complex net of interactions among factors involved in recruitment at different scales, which in turn should be taken into account and incorporated in forthcoming management strategies. ; RB was funded by a Marie Curie IEF fellowship (FP7-PEOPLE-2011-IEF). Funding was also 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), FunDivEUROPE (CE: FP7-ENV-2010. 265171), and IMBALANCE-P (ERC Synergy project SyG-2013-610028).
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Genetics to the rescue: managing forests sustainably in a changing world
There is growing concern that the implementation of political agreements on climate change and biodiversity will not be enough to protect forests in the short run and up to the end of the 21st century. As mitigation efforts are lagging behind self-imposed, reasonable targets, genetic diversity will have a large and significant part to play in the process of adapting forests to climate change. Genetic diversity, the raw material of evolution, can be used for adaptation by natural selection and artificial breeding, in naturally regenerated and plantation forests alike. The two-day scientific conference: "#rescueforests: Genetics to the rescue - Managing forests sustainably in a changing world", addressed the genetic diversity of forests. More specifically, the conference was about natural as well as assisted adaptive processes, their spatial scale, from fine grain to landscape and ecoregions, and how much of the genome it involves. It also dealt with phenotypes and how much of their variation is determined by underlying genetic diversity. And finally, and perhaps most importantly, the conference emphasized the importance of conservation and sustainable use of this genetic diversity as a nature-based solution to adapt under the fast pace of climate change. The conference demonstrated how improved knowledge on genomic diversity and evolutionary mechanisms can help to rescue forests, either naturally or by means of management.
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Survival vs. growth trade-off in early recruitment challenges global warming impacts on Mediterranean mountain trees
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).
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Biotic homogenization can decrease landscape-scale forest multifunctionality
Many experiments have shown that local biodiversity loss impairs the ability of ecosystems to maintain multiple ecosystem functions at high levels (multifunctionality). In contrast, the role of biodiversity in driving ecosystem multifunctionality at landscape scales remains unresolved. We used a comprehensive pan-European dataset, including 16 ecosystem functions measured in 209 forest plots across six European countries, and performed simulations to investigate how local plot-scale richness of tree species (α-diversity) and their turnover between plots (β-diversity) are related to landscape-scale multifunctionality. After accounting for variation in environmental conditions, we found that relationships between α-diversity and landscape-scale multifunctionality varied from positive to negative depending on the multifunctionality metric used. In contrast, when significant, relationships between β-diversity and landscape-scale multifunctionality were always positive, because a high spatial turnover in species composition was closely related to a high spatial turnover in functions that were supported at high levels. Our findings have major implications for forest management and indicate that biotic homogenization can have previously unrecognized and negative consequences for large-scale ecosystem multifunctionality. ; We thank the Hainich National Park administration as well as Felix Berthold and Carsten Beinhoff for support of this study and Gerald Kaendler and the Johann Heinrich von Thünen-Institut for providing access to the German National Forest Inventory data. The research leading to these results received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under Grant Agreement 265171. ; This is the final version of the article. It first appeared from the National Academy of Sciences via https://doi.org//10.1073/pnas.1517903113
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Jack-of-all-trades effects drive biodiversity-ecosystem multifunctionality relationships in European forests
In: https://www.repository.cam.ac.uk/handle/1810/254810
There is considerable evidence that biodiversity promotes multiple ecosystem functions (multifunctionality), thus ensuring the delivery of ecosystem services important for human well-being. However, the mechanisms underlying this relationship are poorly understood, especially in natural ecosystems. We develop a novel approach to partition biodiversity effects on multifunctionality into three mechanisms and apply this to European forest data. We show that throughout Europe, tree diversity is positively related with multifunctionality when moderate levels of functioning are required, but negatively when very high function levels are desired. For two well-known mechanisms, 'complementarity' and 'selection', we detect only minor effects on multifunctionality. Instead a third, so far overlooked mechanism, the 'jack-of-all-trades' effect, caused by the averaging of individual species effects on function, drives observed patterns. Simulations demonstrate that jack-of-all-trades effects occur whenever species effects on different functions are not perfectly correlated, meaning they may contribute to diversity-multifunctionality relationships in many of the world's ecosystems. ; The research leading to these results received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 265171. ; This is the final version of the article. It first appeared from Nature Publishing Group via http://dx.doi.org/10.1038/ncomms11109
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Positive biodiversity-productivity relationship predominant in global forests
The biodiversity-productivity relationship (BPR) is foundational to our understanding of the global extinction crisis and its impacts on ecosystem functioning. Understanding BPR is critical for the accurate valuation and effective conservation of biodiversity. Using ground-sourced data from 777,126 permanent plots, spanning 44 countries and most terrestrial biomes, we reveal a globally consistent positive concave-down BPR, showing that continued biodiversity loss would result in an accelerating decline in forest productivity worldwide.The value of biodiversity in maintaining commercial forest productivity alone—US$166 billion to 490 billion per year according to our estimation—is more than twice what it would cost to implement effective global conservation.This highlights the need for a worldwide reassessment of biodiversity values, forest management strategies, and conservation priorities. ; This work was supported in part by West Virginia University under the United States Department of Agriculture (USDA) McIntire-Stennis Funds WVA00104 and WVA00105; U.S. National Science Foundation (NSF) Long-Term Ecological Research Program at Cedar Creek (DEB-1234162); the University of Minnesota Department of Forest Resources and Institute on the Environment; the Architecture and Environment Department of Italcementi Group, Bergamo (Italy); a Marie Skłodowska Curie fellowship; Polish National Science Center grant 2011/02/A/NZ9/00108; the French L'Agence Nationale de la Recherche (ANR) (Centre d'Étude de la Biodiversité Amazonienne: ANR-10-LABX-0025); the General Directory of State Forest National Holding DB; General Directorate of State Forests, Warsaw, Poland (Research Projects 1/07 and OR/2717/3/11); the 12th Five-Year Science and Technology Support Project (grant 2012BAD22B02) of China; the U.S. Geological Survey and the Bonanza Creek Long Term Ecological Research Program funded by NSF and the U.S. Forest Service (any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. government); National Research Foundation of Korea (grant NRF-2015R1C1A1A02037721), Korea Forest Service (grants S111215L020110, S211315L020120 and S111415L080120) and Promising-Pioneering Researcher Program through Seoul National University (SNU) in 2015; Core funding for Crown Research Institutes from the New Zealand Ministry of Business, Innovation and Employment's Science and Innovation Group; the Deutsche Forschungsgemeinschaft (DFG) Priority Program 1374 Biodiversity Exploratories; Chilean research grants Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT) 1151495 and 11110270; Natural Sciences and Engineering Research Council of Canada (grant RGPIN-2014-04181); Brazilian Research grants CNPq 312075/2013 and FAPESC 2013/TR441 supporting Santa Catarina State Forest Inventory (IFFSC); the General Directorate of State Forests, Warsaw, Poland; the Bavarian State Ministry for Nutrition, Agriculture, and Forestry project W07; the Bavarian State Forest Enterprise (Bayerische Staatsforsten AöR); German Science Foundation for project PR 292/12-1; the European Union for funding the COST Action FP1206 EuMIXFOR; FEDER/ COMPETE/POCI under Project POCI-01-0145-FEDER-006958 and FCT–Portuguese Foundation for Science and Technology under the project UID/AGR/04033/2013; Swiss National Science Foundation grant 310030B_147092; the EU H2020 PEGASUS project (no 633814), EU H2020 Simwood project (no 613762); and the European Union's Horizon 2020 research and innovation program within the framework of the MultiFUNGtionality Marie Skłodowska-Curie Individual Fellowship (IF-EF) under grant agreement 655815. The expeditions in Cameroon to collect the data were partly funded by a grant from the Royal Society and the Natural Environment Research Council (UK) to Simon L. Lewis.
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Positive biodiversity-productivity relationship predominant in global forests
The biodiversity-productivity relationship (BPR) is foundational to our understanding of the global extinction crisis and its impacts on ecosystem functioning. Understanding BPR is critical for the accurate valuation and effective conservation of biodiversity. Using ground-sourced data from 777,126 permanent plots, spanning 44 countries and most terrestrial biomes, we reveal a globally consistent positive concave-down BPR, showing that continued biodiversity loss would result in an accelerating decline in forest productivity worldwide. The value of biodiversity in maintaining commercial forest productivity alone—US$166 billion to 490 billion per year according to our estimation—is more than twice what it would cost to implement effective global conservation. This highlights the need for a worldwide reassessment of biodiversity values, forest management strategies, and conservation priorities.
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