Ester González de Andrés

Increased complementarity in water-limited environments in Scots pine and European beech mixtures under climate change

Ramon y Cajal contract, Grant/Award Number:RYC‐2011‐08082; Spanish Ministry of Economy and Competitiveness, Grant/AwardNumber: AGL2012‐33465; mobility aid,Grant/Award Number: EEBB‐I‐15‐09220; Spanish Predoctoral Research Grant, Grant/Award Number: BES‐2013‐066705.

Tree‐to‐tree competition in mixed European beech–Scots pine forests has different impacts on growth and water‐use efficiency depending on site conditions

Mixed conifer–hardwood forests can be more productive than pure forests and they are increasingly considered as ecosystems that could provide adaptation strategies in the face of global change. However, the combined effects of tree-to-tree competition, rising atmospheric CO2 concentrations and climate on such mixtures remain poorly characterized and understood. To fill this research gap, we reconstructed 34-year series (1980–2013) of growth (basal area increment, BAI) and intrinsic water-use efficiency (iWUE) of Scots pine (Pinus sylvestris L.)–European beech (Fagus sylvatica L.) mixed stands at two climatically contrasting sites located in the southwestern Pyrenees. We also gathered data on tree-to-tree competition and climate variables in order to test the hypotheses that (1) radial growth will be greater when exposed to inter- than to intraspecific competition, that is, when species complementarity occurs and (2) enhanced iWUE could be linked to improved stem radial growth. Growth of both species was reduced when intraspecific competition increased. Species complementarity was linked to improved growth of Scots pine at the continental site, while competition overrode any complementarity advantage at the drought-prone Mediterranean site. Beech growth did not show any significant response to pine admixture likely due to shade tolerance and the highly competitive nature of this species. Increasing interspecific competition drove recent iWUE changes, which increased in Scots pine but decreased in European beech. The iWUE enhancement did not involve any growth improvement in Scots pine. However, the positive BAI-iWUE relationship found for beech suggests an enhanced beech growth in drought-prone sites due to improved water use. Synthesis. Complementarity may enhance growth in mixed forests. However, water scarcity can constrict light-related complementarity for shade intolerant species (Scots pine) in drought-prone sites. Basal area increment–intrinsic water-use efficiency relationships were negative for Scots pine and positive for European beech. These contrasting behaviours have got implications for coping with the expected increasing drought events in Scots pine–European beech mixtures located near the ecological limit of the two species. Complementarity effects between tree species should be considered to avoid overestimating the degree of future carbon uptake by mixed conifer–broadleaf forests.

Modelling mixed forest stands: Methodological challenges and approaches

Mixedwoods are increasingly becoming one of the major focuses in ecological modelling studies, due to their higher productivity and resiliency compared to monocultures. In this chapter, we provide a review on the state-of-the-art of models simulating mixedwood stands. After reviewing almost 400 peer-reviewed publications, it is clear that most modelling exercises are done for explanatory uses rather than for decision-making support tools. Among them, North America and central Europe are the main model development centers. It is also clear that more model portability is needed, as even the most widely distributed models tend to be used in the same region where they were originally developed. Finally, the four models used more widely for simulating mixed forests stands were identified: two have been applied mostly in boreal/temperate ecosystems (FORECAST and SILVA), whereas the other two have been used in tropical/subtropical environments (FORMIND and FORMIX). A comparison of their different modelling approaches is provided, and multimodel exercises are suggested as a way to both compare model performance and also to reduce simulation uncertainty due to model selection.Abstract Mixedwoods are increasingly becoming one of the major focuses in ecological modelling studies, due to their higher productivity and resiliency compared to monocultures. In this chapter, we provide a review on the state-of-the-art of models simulating mixedwood stands. After reviewing almost 400 peer-reviewed publications, it is clear that most modelling exercises are done for explanatory uses rather than for decision-making support tools. Among them, North America and central Europe are the main model development centers. It is also clear that more model portability is needed, as even the most widely distributed models tend to be used in the same region where they were originally developed. Finally, the four models used more widely for simulating mixed forests stands were identified: two have been applied mostly in boreal/temperate ecosystems (FORECAST and SILVA), whereas the other two have been used in tropical/subtropical environments (FORMIND and FORMIX). A comparison of their different modelling approaches is provided, and multimodel exercises are suggested as a way to both compare model performance and also to reduce simulation uncertainty due to model selection.

Papel de los factores bióticos y las sequías en el decaimiento del bosque: aportaciones desde la dendroecología

Sanguesa-Barreda, G., Camarero, J.J., Linares, J.C., Hernandez, R., Oliva, J., Gazol, A., et al. 2015. Role of biotic factors and droughts in the forest decline: contributions from dendroecology. Ecosistemas 24(2): 15-23. Doi.: 10.7818/ECOS.2015.24-2.03. Increasing mortality and decline of forests are affecting several tree species and biomes. These events of forest decline have been related to the interaction of several global change elements, like the increase in drought stress or a higher incidence of biotic stress factors. However, the roles played by biotic stressors have been scarcely explored as related to drought stress. In this paper we retrospectively characterize the effects of these organisms on radial growth of trees already stressed by drought using dendrochronology. The combined effect of mistletoe and droughts reduce tree growth in Scots pine and increase defoliation, being these effects more noticeable in the apex. The pine processionary moth induces growth losses in the affected stands of black pine, but they usually recover two years after the outbreak. We did not find a determinate role of root pathogens on silver fir dieback. Finally, dead Aleppo pine trees infested by bark beetles showed similar growth patterns than living pine trees. This study allows characterizing some of the complex and multiple effects of different biotic stressors on growth and vulnerability of forests subjected to the negative effects exerted by droughts.

Están los bosques mixtos pirenaicos de pino silvestre y haya en el camino hacia la saturación por nitrógeno

Rocío Alonso Miguel Álvarez Cobelas Jose Manuel Álvarez-Martínez Mariano Amoroso Enrique Andivia Gabriel Arellano Cristina Armas María Arróniz Crespo Anna Avila Isabel Banos-González Eulogio Bedmar Raquel Benavides Marta Benito Garzón Juan A. Blanco Francisco Javier Bonet García Raphael Boulay Santiago Fernando Burneo Francisco Cabezas Rafael Calama Silvia Calvo Aranda Julio A. Camargo Daisy Cárate-Tandalla José A. Carreira de la Fuente Myriam Catalá Miquel De Cáceres Pilar de la Rua Thibaut Dominique Delsinne Dennis Denis Lucía DeSoto Suárez María T. Domínguez David A. Donoso David A Donoso Jorge Durán María José Endara Blanca Figueroa-Rangel Rubén G. Mateo José M. García del Barrio Enrique García de la Riva Ana I. García-Cervigón Morales Héctor García-Gómez Óscar Godoy Uriel Hernandez Gomez Lorena Gémez Aparicio Penélope González José González Novoa Manuela González Suárez Daniel Griffith Roberto José Guerrero David Gutiérrez Xavier Haro Carrión Laura Hernández Mateo Javier Herrero Asier Herrero Méndez Sheila Izquieta Rojano Luis Lassaletta John Lattke Alex Leverkus Francisco Lloret Jorge Lozano Yudi Lozano Manuel Macía Jaime Madrigal González Esteban Manrique Santiago Martín Alcón Pilar Martín Isabel Javier Martínez Abaigar Jesús Martínez Fernández José Luis Martínez Menéndez Isabel Martínez Moreno Francisco Javier Martínez Vega Marcos Méndez Iglesias Rubén Milla Marcos Miñarro Daniel Moya Navarro Sven Mutke Rafael Ma Navarro Cerrillo Francisco Bruno Navarro Reyes Susana Ochoa Gaona Raúl Ochoa Hueso Daniel Paredes Mauricio Parra Quijano Sergio Pérez Guerrero Carolina Puerta Piñero Neptalí Ramírez-Marcial José V. Roces Díaz Alexandra Rodríguez Carlos Rodríguez Osorio Itziar Rodríguez Urbieta Susana Rodríguez-Echeverría Pere Rovira Paloma Ruiz-Benito Asunción Saldaña Ángela Sánchez-Miranda Fábio Suzart de Albuquerque María Fernanda Tapia-Armijos Jerónimo Torres-Porras María Triviño Raúl Vaca Alejandro Valdecantos Jordi Vayreda Alejandro Velázquez Martínez Albert Vila-Cabrera Rafael Villar Francisco Javier Zamora Camacho Carlos Zamorano-Elgueta Galo Zapata Ríos Lista de revisores que han completado revisiones en el año 2016Visconti, F., de Paz, J.M. 2017. Estimation of the potential CO 2 sequestration and emission capacity of the agricultural soils of the Valencian Community. Ecosistemas 26(1): 91-100. Doi.: 10.7818/ECOS.2017.26-1.15 Agricultural soils have capacity to sequester CO 2 in the form of organic matter. However, this capacity has hardly been quantified and mapped for large territories and with a wide variety of crops, such as the Valencian Community. This task is required to properly size the role of agriculture in any strategy to mitigate climate change. In this paper a first estimate of the potential CO 2 sequestration and emission capacity of the agricultural soils of the Valencian Community down to 20 cm depth has been made. This estimate has been carried out based on the average and spatial variability of the agricultural soil organic matter content in homogeneous agro-ecological zones in climate, soil class and land use, and using GIS, geostatistics and map algebra techniques. The sequestration and emission capacities were found to be 24.0 and 22.0 Mt of carbon, respectively. These values are equivalent to roughly ± 8 years of carbon emissions by use of fossil fuels in the Community itself. This sequestering capacity, which could be reached in 15 to 100 years with the global adoption of management practices that foster soil organic matter accumulation, has an important but insufficient effect compared to the current emission rate. In any case, increasing carbon sequestration in soils, either through management improvement or through organic matter incorporation programs, is very important both to improve sequestration capacity and even more to adapt agroecosystems to climate change.