Open Access
Determinants and tools to evaluate the ecological sustainability of using forest biomass as an alternative energy source
(2018) Blanco Vaca, Juan Antonio; Candel Pérez, David; Lo, Yueh-Hsin; Ciencias; Zientziak; Gobierno de Navarra / Nafarroako Gobernua, PI037 InFORest
Forest biomass, the most ancient of fuels, is again in the center of renewable energy production. This chapter provides an introductory view of the main factors that condition the ecological sustainability of this energy source. The basic concepts of ecological sustainability, ecological rotation, and ecological thresholds (among others) are presented. The state of the art on approaches to assess the sustainability of forest biomass production for heat and electricity is discussed, and tools available for decision-makers to evaluate the sustainability of forest biomass production and management are described. This chapter then describes the main advantages and drawbacks of forest certification, growth and yield tables, and ecological models in relationship to their use in sustainable forest management for biomass and energy production.
Open Access
Simulando la interacción entre la densidad inicial y los flujos de agua y nutrientes para comprender el desarrollo de rodales mixtos de Pinus sylvestris y Fagus sylvatica bajo cambio climático
(Asociación Española de Ecología Terrestre, 2017) Candel Pérez, David; Blanco Vaca, Juan Antonio; González de Andrés, Ester; Lo, Yueh-Hsin; Imbert Rodríguez, Bosco; Castillo Martínez, Federico; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
La gestión de bosques mixtos se ha convertido en una estrategia de adaptación para reducir los riesgos relacionados con el cambio climático. A su vez, los modelos ecológicos pueden ser una herramienta útil para el estudio del crecimiento y la productividad de dichas masas. En este trabajo se presenta una evaluación de la capacidad del modelo híbrido “FORECAST Climate” de simular el estrés hídrico y la productividad en bosques mixtos de pino silvestre y haya en Navarra (norte de España) y su interacción con distintos niveles de densidad de regenerado. En el estudio se incluyeron tres escenarios climáticos para comprobar la capacidad del modelo para simular los flujos de agua bajo condiciones de cambio climático. Las estimaciones del modelo tanto de estrés hídrico como de acumulación de biomasa se mostraron sensibles a la reducción en la densidad de regeneración inicial. Los resultados indicaron que el modelo muestra la suficiente capacidad para simular los efectos de la competencia entre especies en la mortalidad de árboles en bosques mixtos y estimar variables relacionadas con los flujos hídricos. Por un lado, los efectos más significativos de la densidad del rodal sobre la disponibilidad hídrica aparecen durante la primera etapa de desarrollo, mientras que, por otro, el estrés hídrico es mayor en el caso del haya, aunque la reducción de la competencia podría compensar dicho aumento. Las implicaciones de este trabajo para la gestión adaptativa de bosques mixtos sugieren el actual control de la densidad para que los efectos acumulativos sean significativos en próximas décadas.
Open Access
6ª Edición de la Escuela de verano de Ecología de Navarra. Cambio global y paisajes resilientes
(Asociación Española de Ecología Terrestre (AEET), 2020) Canals Tresserras, Rosa María; Candel Pérez, David; Agronomía, Biotecnología y Alimentación; Agronomia, Bioteknologia eta Elikadura; Ciencias; Zientziak
Del 7 al 9 de septiembre de 2020 tuvo lugar en formato semipresencial la 6ª edición de la Escuela de Verano de Ecología de Navarra de la Universidad Pública de Navarra (UPNA) con el título Cambio global y paisajes resilientes.
Open Access
Calculadora de sostenibilidad FIRST-Heat Navarra: generando energía sostenible al reducir el riesgo de incendios forestales en comunidades rurales
(Sociedad Española de Ciencias Forestales, 2020) Candel Pérez, David; Blanco Vaca, Juan Antonio; Lo, Yueh-Hsin; Montero, Eduardo; Barrena Figueroa, Ramo; Castillo Martínez, Federico; Ciencias; Zientziak; Gestión de Empresas; Enpresen Kudeaketa
El cambio climático, la expansión urbanística o el aumento del uso recreativo en zonas forestales están aumentando la probabilidad de ocurrencia de incendios forestales. Las comunidades rurales pueden afrontar la oportunidad de combinar actividades silvícolas para reducir el riesgo de incendios con el desarrollo energético basado en el aprovechamiento de la biomasa forestal generada. Para demostrar la viabilidad de este tipo de gestión, se ha creado una herramienta informática demostrativa de apoyo a la toma de decisiones. Mediante la modificación y calibración del modelo ecológico FORECAST, se simularon las condiciones de diferentes localidades y especies forestales de Navarra. Sobre dichas simulaciones, se ha desarrollado la interfaz de usuario de esta calculadora (Fire Interface Rural Screening Tool for Heating: FIRST-Heat Navarra), que pretende estimar la sostenibilidad ecológica y socio-económica del uso de la biomasa forestal a nivel local. Esta herramienta se muestra capaz de simular los efectos del cambio en las condiciones de crecimiento del bosque mediante un modelo ecológico dinámico. También presenta la capacidad de integrar, resumir y comunicar de forma efectiva el último conocimiento científico sobre ecología forestal, y el conocimiento técnico, económico y social sobre la tecnología de calefacción de distrito a partir de biomasa.
Open Access
Drought-induced changes in wood density are not prevented by thinning in Scots pine stands
(MDPI, 2018) Candel Pérez, David; Lo, Yueh-Hsin; Blanco Vaca, Juan Antonio; Chiu, Chih-Ming; Camarero, Jesús Julio; González de Andrés, Ester; Imbert Rodríguez, Bosco; Castillo Martínez, Federico; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
Density is an important wood mechanical property and an indicator of xylem architecture and hydraulic conductivity. It can be influenced by forest management and climate. We studied the impact of thinning and climate variables on annual stem radial growth (ring width and ring density, and their earlywood and latewood components) in two contrasting Scots pine (Pinus sylvestris L.) stands in northern Spain (one continental, one Mediterranean). At each site, three thinning regimes (control or T0, removing 20% basal area or T20, and removing 30% or T30) were randomly applied to nine plots per site (three plots per treatment) in 1999. Thinning was repeated at the Mediterranean site in 2009 (increasing thinning intensity in T30 to 40%). Eight trees per plot were cored in spring 2014. Second thinning at the Mediterranean site and first thinning at the continental site generally caused significantly wider ring (RW), earlywood (EW) and latewood (LW) widths, although no differences between T20 and T30/40 were found, supporting in part the common observation that radial growth is enhanced following thinning as competition for water and nutrients is reduced. At the Mediterranean site, values of latewood density (LD) and maximum density (Dmax) relative to pre-thinning conditions were significantly lower in T0 than in T30. However, at the continental site, relative changes of ring density (RD) and LD were significantly higher in T0 than in T20 and T30. Climate significantly affected not only RWbut also RD, with significant RD drops during or right after unusually warm-dry years (e.g., 2003, 2011), which were characterized by LD reductions between 5.4 and 8.0%. Such RD decreases were quickly followed by recovery of pre-drought density values. These results indicate trees temporarily reduce LD as a way to enhance hydraulic conductivity during dry summers. However, climate effects on wood density were site-dependent. We also detected that the thinning effect was not intense enough to prevent drought-induced changes in wood density by altering water availability, but it could help to reduce wood properties fluctuations and therefore maintain more homogeneous wood mechanic features.
Open Access
Assessing tree drought resistance and climate-growth relationships under different tree age classes in a pinus nigra arn. Ssp. salzmannii forest
(MDPI, 2021) Lucas Borja, Manuel Esteban; Bose, Arun K.; Andivia, Enrique; Candel Pérez, David; Plaza-Álvarez, Pedro A.; Linares, Juan C.; Institute for Multidisciplinary Research in Applied Biology - IMAB
The magnitude of drought impact in forest ecosystems depends on which group of trees are more severely affected; greater mortality of smaller trees can modulate the trajectories of succession, while the mortality of larger trees can disproportionately offset the ecosystem’s carbon balance. Several studies have documented a greater vulnerability of large trees to extreme droughts while some other studies reported a greater growth reduction in smaller trees during droughts. We tested these hypotheses by comparing tree basal area increment (BAI), drought resistance (i.e., magnitude of growth decline during drought), and resilience (i.e., magnitude of growth recovery after drought) across five different age-classes in black pine (Pinus nigra Arn. Ssp salzmannii) forests in Spain. Our results showed that the BAI patterns, drought resistance, and resilience were strongly influenced by tree age-classes. In addition, the effect of climatic water balance (precipitation minus potential evapotranspiration) on BAI significantly varied among age-classes. The effect of water balance on BAI was lower for younger age-classes (1–39 years of age) compared to older age-classes. We observed a greater growth reduction (i.e., lower resistance) in older trees (>40 years of age) during droughts compared to younger trees (<40 years of age). However, all trees, irrespective of their ages, were able to recover the growth rates after the drought. In general, younger trees showed a greater capacity in recovering the growth rate (i.e., more resilient) than older trees. We detected no significant effects of stand basal area and stand density on BAI, drought resistance, and resilience. Overall, our results indicated that growth of older trees was more negatively affected during drought. Therefore, these older/larger trees can be selected for commercial thinning, or can be released from competition, which can minimize the potential impacts of future droughts in black pine forests in Spain.
Open Access
Seed origin and protection are important factors affecting post-fire initial recruitment in pine forest areas
(MDPI, 2017) Lucas Borja, Manuel Esteban; Candel Pérez, David; Onkelinx, Thierry; Fule, Peter Z.; Moya, Daniel; Heras, Jorge de las; Tíscar, Pedro A.; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
Initial seedling recruitment is one of the most critical stages for plants in the Mediterranean basin. Moreover, wildfires and post-fire environmental conditions might deteriorate regeneration success, which can lead to problems for sustainable forest restoration and forest persistence. On this context, different seed origins and pine species may be better adapted to new environmental conditions remaining after forest fires and seed protection might modulate seedling initial recruitment. This study evaluates the effects of seed origin (Pinus nigra Arn. subsp. salzmannii Dunal (Franco) from lowland, midland and upland distribution areas), pine species (Pinus pinaster Aiton, Pinus sylvestris L. and Pinus nigra Arn. subsp. salzmannii Dunal (Franco)) and seed protection on seed emergence and early seedling survival after forest fires in the Cuenca Mountains. In addition, a greenhouse experiment was set up under controlled conditions to test seedling performance and to compare initial seedling growth of different P. nigra seed origins growing in field and greenhouse conditions. Results showed that wetter spring seasons and P. nigra seed origins from midland and upland distribution growing in their natural habitat distribution perform better that P. sylvestris and P. pinaster. Seed protection is an important factor modulating the above-mentioned trend. P. nigra seeds growing at the greenhouse experiment showed differences in growth for extreme (upland or lowland) P. nigra distribution.
Open Access
Synergies between climate change, biodiversity, ecosystem function and services, indirect drivers of change and human well-being in forests
(Springer, 2021) Imbert Rodríguez, Bosco; Blanco Vaca, Juan Antonio; Candel Pérez, David; Lo, Yueh-Hsin; González de Andrés, Ester; Yeste Yeste, Antonio; Herrera Álvarez, Ximena; Rivadeneira Barba, Gabriela; Liu, Yang; Chang, Shih-Chieh; Ciencias; Zientziak
Climate change is having impacts on the biodiversity and structure of many ecosystems. In this chapter, we focus on its impacts on forests. We will focus on how the potential climate change impacts on forest biodiversity and structure will have a reflection on the ecosystem services provided by forests, and therefore on the capacity of these ecosystems to support the Sustainable Development Goals set by the United Nations. The chapter will be organized in three sections, considering boreal, temperate, and tropical forests along each section. The first section will deal with the synergies or interactions between climate change, biodiversity, and ecosystem function with emphasis not only on plants but also on fungi, animals, and prokaryotes. Synergies between climate change and ecosystem services will be described and analyzed in the second section. To better link the first two sections, we will explore the relationships between ecosystem function, species traits, and ecosystem services. Finally, case studies for boreal, Mediterranean, and tropical forests will be presented, emphasizing the synergies between the above factors, the indirect drivers of change (demographic, economic, sociopolitical, science and technology, culture and religion), and human well-being (basic materials for a good life, health, good social relations, freedom of choice and actions) in forests.
Open Access
Afforestation with Pinus nigra Arn ssp salzmannii along an elevation gradient: controlling factors and implications for climate change adaptation
(Springer, 2021) Lucas Borja, Manuel Esteban; Jing, Xing; Candel Pérez, David; Parhizkar, Misagh; Rocha, Francisco; Heydari, Medhi; Muñoz-Rojas, Miriam; Zema, Demetrio Antonio; Ciencias; Zientziak
Key Message: the first bottleneck in Spanish black pine survival through afforestation is the lack of resistance to drought in their initial life stages. Abstract: Spanish black pine (Pinus nigra Arn ssp. salzmannii) is the most widely distributed pine species in mountain areas of the Mediterranean Basin and is commonly used for afforestation in endangered and degraded areas. Despite its importance, little is known regarding the factors driving seedling survival for this species, which may hamper afforestation success in Mediterranean areas. In this study, we assessed the effects of seed origin and plantation site along a natural gradient with contrasting elevation and climatic conditions in a Mediterranean forest in Central-Eastern Spain. Our results showed: (1) higher seedling survival rates when seed origin differed from plantation site (25.3 ± 5.4%) compared to same origin and plantation site (5.3 ± 2.7%); (2) higher survival probability (~ 20%) for high and medium elevation seeds (colder and wetter locations) compared to the warmer and drier low elevation sites (15%); (3) higher seedling survival (~ 40%) at higher elevation sites compared to low-elevation sites (< 20%); and (4) increased hazard of seedling death with decreasing elevation of the plantation site. We also reported a complete mortality at the drier sites after the first summer following the plantation. Overall, the combination of seeds from medium elevation and high elevation plantation sites increased the survival of Spanish black pine. These results have direct implications for forest management of Spanish black pine in Mediterranean regions, particularly in current and future climate change scenarios.