Open Access
Climate-forest-water-people relations: seven system delineations
(2018) Noordwijk, Meine van; Creed, Irena F.; Jones, Julia A.; Wei, Xiaohua; Gush, Mark; Blanco Vaca, Juan Antonio; Sullivan, Caroline A.; Bishop, Kevin; Murdiyarso, Daniel; Xu, Jianchu; Claassen, Marius; McNulty, Steven G.; Ellison, David; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
In this chapter, we review current scientific understanding and hypotheses at seven system delineations that build up from the level of a ‘tree’ interacting with water, to that of a social-ecological system at the scale of landscapes. A system delineation separates internal entities that interact dynamically from external entities that may have a one-way influence but are not significantly influenced by feedback from within the system boundaries. Each system level has its characteristic outcomes or results.
Open Access
Gestión forestal sostenible de masas de pino silvestre en el Pirineo Navarro
(Asociación Española de Ecología Terrestre, 2003) Castillo Martínez, Federico; Imbert Rodríguez, Bosco; Blanco Vaca, Juan Antonio; Traver, Carmen; Puertas, Fernando; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
La política forestal actual se caracteriza por un compromiso hacia una gestión ecológicamente sostenible de los ecosistemas forestales. Para poder realizarla es necesario conocer los factores que afectan al uso de los bosques, entre los cuales los hay de tipo social, económico, legal, técnico y ecológico. Los beneficios que producen los bosques podrían desaparecer si la estabilidad de las masas forestales es afectada por las actividades humanas. Asumiendo que la explotación de los bosques es necesaria para la economía regional, debemos asegurarnos que el uso de los bosques no ponga en peligro la existencia de éstos. La gestión sostenible de los ecosistemas forestales intenta así compaginar la explotación forestal con el mantenimiento de la biodiversidad y la función del ecosistema. Presentamos aquí algunos aspectos de ecología y gestión forestal en el marco de un proyecto de investigación realizado por la Universidad Pública de Navarra y el Gobierno de Navarra para estudiar la forma de mejorar la producción de madera en bosques de pino albar (Pinus sylvestris L.) y las consecuencias que su explotación pueda tener sobre aspectos tales como el ciclo de nutrientes y la biodiversidad.
Open Access
¿Están los bosques mixtos pirenaicos de pino silvestre y haya en el camino hacia la saturación por nitrógeno?
(Asociación Española de Ecología Terrestre, 2017) Blanco Vaca, Juan Antonio; San Emeterio Garciandía, Leticia; González de Andrés, Ester; Imbert Rodríguez, Bosco; Larrainzar Rodríguez, Estíbaliz; Peralta de Andrés, Francisco Javier; Lo, Yueh-Hsin; Castillo Martínez, Federico; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
Las actividades humanas causan altos niveles de deposición atmosférica crónica de N que pueden estar trastornando el ciclo del N en los bosques de los Pirineos occidentales. Para probar esta hipótesis, se han investigado los efectos de la deposición de N atmosférico en el ciclo de N en dos bosques mixtos de pino silvestre y haya en Navarra. Un bosque está situado a 1350 m de altitud y tiene un clima continental, mientras que el otro está situado a 650 m y tiene un clima mediterráneo húmedo. Pruebas preliminares indicaron una fijación biológica de N 2 atmosférico indetectable, así como la casi nula presencia de plantas con simbiontes fijadores como en la actividad de fijadores libres. Por lo tanto se asumió que la principal entrada de N en estos bosques es la deposición atmosférica. Se estimó la dependencia de la productividad de estos ecosistemas de la deposición por medio del modelo ecológico FORECAST, calibrado para estos sitios. Se simularon seis escenarios con tasas de deposición en un rango de 5 a 30 kg ha -1 año -1 . Los resultados indicaron que la productividad de estos bosques es dependiente de la deposición de N, pero indicios de saturación por N (aumento de lixiviación y carencia de aumento de productividad) indican que pueden saturarse a partir de 20-25 kg N ha -1 año -1 , unos 5-10 kg N ha -1 año -1 por encima de los niveles observados actualmente.
Open Access
Survival and growth as measures of shade tolerance of planted western redcedar, western hemlock and amabilis fir seedlings in hemlock-fir forests of northern Vancouver Island
(Elsevier, 2017) Weber, Adrian; Leckie, Sara; Kimmins, J.P. (Hamish); Gilbert, Benjamin; Blanco Vaca, Juan Antonio; Lo, Yueh-Hsin; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
We examined two measures of shade tolerance (survival and growth) of planted 1-year-old seedlings of western redcedar (Thuja plicata (Donn ex D. Don)), western hemlock (Tsuga heterophylla ([Raf.] Sarg.)) and amabilis fir (Abies amabilis ([Dougl. ex Loud] Dougl. ex Forbes)). Seedlings were planted at two different sites (forest interior: 4.5% mean above canopy photosynthetically active radiation [ACPAR], and forest edge: 41.5% mean ACPAR), in a 90-year-old, windthrow origin, unmanaged mesic western hemlock-amabilis fir stand. Seedlings were planted in 1997, and re-measured in 1998 and 2001 (after five growing seasons). To assess the effects of deer browsing on redcedar survival and growth, additional seedlings of this species were planted and protected with Vexar© tubes. To examine for nutrient-light interactions, half of these seedlings were fertilized with N-P-K and micronutrients at planting. Western redcedar had high levels of survival after 4 years (98% in edge plots and 93% in interior plots). Redcedar seedlings in edge plots were more vigorous but were browsed more heavily than in the interior plots. At edge sites, the negative effects of the Vexar© tubes may have been lower than their positive effects. Hemlock survival was about 50% in the stand interior but 80% in the edge plots. Amabilis fir in the interior plots had the lowest survival of the three species, with only 40% of initial seedlings surviving over the next four years, but had high survival in edge plots (95%). Height, biomass, and root collar diameter growth were significantly higher in edge plots for fir and hemlock. However, for redcedar, only biomass was significantly higher and no differences were detected for height and diameter. Our results show that shade tolerance cannot be assessed by simple measures of leaf/light relationships alone, but also requires consideration of light, nutrition, growth and browsing.
Open Access
Significant increase in ecosystem C can be achieved with sustainable forest management in subtropical plantation forests
(Public Library of Science, 2014) Wei, Xiaohua; Blanco Vaca, Juan Antonio; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
Subtropical planted forests are rapidly expanding. They are traditionally managed for intensive, short-term goals that often lead to long-term yield decline and reduced carbon sequestration capacity. Here we show how it is possible to increase and sustain carbon stored in subtropical forest plantations if management is switched towards more sustainable forestry. We first conducted a literature review to explore possible management factors that contribute to the potentials in ecosystem C in tropical and subtropical plantations. We found that broadleaves plantations have significantly higher ecosystem C than conifer plantations. In addition, ecosystem C increases with plantation age, and reaches a peak with intermediate stand densities of 1500–2500 trees ha-1. We then used the FORECAST model to simulate the regional implications of switching from traditional to sustainable management regimes, using Chinese fir (Cunninghamia lanceolata) plantations in subtropical China as a study case. We randomly simulated 200 traditional short-rotation pure stands and 200 sustainably-managed mixed Chinese fir – Phoebe bournei plantations, for 120 years. Our results showed that mixed, sustainably-managed plantations have on average 67.5% more ecosystem C than traditional pure conifer plantations. If all pure plantations were gradually transformed into mixed plantations during the next 10 years, carbon stocks could rise in 2050 by 260.22 TgC in east-central China. Assuming similar differences for temperate and boreal plantations, if sustainable forestry practices were applied to all new forest plantation types in China, stored carbon could increase by 1,482.80 TgC in 2050. Such an increase would be equivalent to a yearly sequestration rate of 40.08 TgC yr-1, offsetting 1.9% of China’s annual emissions in 2010. More importantly, this C increase can be sustained in the long term through the maintenance of higher amounts of soil organic carbon and the production of timber products with longer life spans.
Open Access
Changes in long-term light properties of a mixed conifer–broadleaf forest in Southwestern Europe
(MDPI, 2021) Ruiz de la Cuesta Vela, Ignacio; Blanco Vaca, Juan Antonio; Imbert Rodríguez, Bosco; Peralta de Andrés, Francisco Javier; Rodríguez Pérez, Javier; Ciencias; Zientziak; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
Natural and anthropogenic factors affect forest structure worldwide, primarily affecting forest canopy and its light properties. However, not only stand-replacing events modify canopy structure, but disturbances of lower intensity can also have important ecological implications. To study such effects, we analyzed long-term changes in light properties of a conifer–broadleaf mixed forest in the Southwestern Pyrenees, placed in the fringe between the Mediterranean and Eurosi- berian biogeographical regions. At this site, a thinning trial with different intensities (0%, 20%, and 30–40% basal area removed) took place in 1999 and 2009, windstorms affected some plots in 2009 and droughts were recurrent during the sampling period (2003, 2005, 2011). We monitored light properties during 14 years (2005–2019) with hemispherical photographs. We applied partial autocorrelation functions to determine if changes between years could be attributed to internal canopy changes or to external disturbances. In addition, we mapped the broadleaf canopy in 2003, 2008, and 2016 to calculate broadleaf canopy cover and richness at the sampling points with different buffer areas of in- creasing surface. We applied generalized linear mixed models to evaluate the effects of light variables on canopy richness and cover. We found that light variables had the most important changes during the period 2008 to 2010, reacting to the changes caused that year by the combined effects of wind and forest management. In addition, we found that an area of 4.0 m radius around the sampling points was the best to explain the relationship between light properties and species richness, whereas a radius of 1.0 m was enough to estimate the relationship between light and canopy cover. In addition, light-related variables such as diffuse light and leaf area index were related to species richness, whereas structural variables such as canopy openness were related to canopy cover. In summary, our study demonstrates that non stand-replacing disturbances such as windstorms, thinning, or droughts can have an important role in modifying structural and light-related canopy properties, which in turn may inﬂuence natural processes of stand development and ecological succession.
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
Determinants of the forest-water relationship
(2018) McNulty, Steven G.; Archer, Emma; Gush, Mark; Noordwijk, Meine van; Ellison, David; Blanco Vaca, Juan Antonio; Xu, Jianchu; Bishop, Kevin; Wei, Xiaohua; Vira, Bhaskar; Creed, Irena F.; Mukherji, Aditi; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
Our analysis of forest-water relations addresses four important subsystems of a linked planetary social-ecological system: climate, forests, water and people. In this chapter, we consider how each of these subsystems is changing (trend) and what is causing the change (’determinant’). We discuss the critical determinants of change in forests as they relate to water quality and quantity. Chapter 4 then presents the impacts of these changes on water quality and quality.
Open Access
First-ever complete list of amazonian timber tree species
(Wiley, 2023) Herrera Álvarez, Ximena; Blanco Vaca, Juan Antonio; Phillips, Oliver L.; Guadalupe, Vicente; Ortega-López, Leonardo D.; Steege, Hans ter; Rivas-Torres, Gonzalo; Ciencias; Zientziak
We compiled and presented a dataset (named “MADERA”) for all timber species reported in the Amazon region from all nine South American Amazonian countries. This work was based on official information from every country and on two substantial scientific references. Our final Amazonian timber species dataset contains 1,112 unique species records, which belong to 337 genera and 72 families from the lowland Amazonian rainforest, with associated information related to population, conservation (IUCN Red list categories), and trade status (ITTO/CITES) of each species. The authors of this research expect that the information provided will be useful to strengthen sustainable forest management and scientific research in the Amazonian region.
Open Access
Douglas-fir radial growth in interior British Columbia can be linked to long-term oscillations in Pacific and Atlantic sea surface temperatures
(NCR Research Press, 2017) Lo, Yueh-Hsin; Blanco Vaca, Juan Antonio; Guan, Biing T.; Ciencias del Medio Natural; Natura Ingurunearen Zientziak
A major problem in modern dendrochronology is that the methods traditionally used for linking tree ring growth data to climate records are not well suited to reconstructing low-frequency climatic variations. In this study, we explored the alternative Ensemble Empirical Mode Decomposition to detrend tree-ring records and to extract climate signals without removing low-frequency information. Tree cores of Pseudotsuga menziesii var. glauca (Mayr.) Franco were examined in a semi-arid forest in southern interior British Columbia, western Canada. Ring width data were decomposed into five oscillatory components (intrinsic mode functions, IMFs) of increasingly longer periodicities. IMF 1 was considered white noise, IMF 2 was used to create the first diameter growth index (DGI-1), IMF 3 and IMF 4 were combined to create the second diameter growth index (DGI-2), whereas IMF 5 and the residual term together were considered as the trend term. The highest significant cross-correlations between DGI-1 and the NAOAugust, NIÑO12May, and PDOJanuary indices were found at 1-year lags. DGI-2 had positive and persistent correlations with NAOJune and PDOMay at 0 to 3 years lags, and with NAOMay at 2 and 3 years lags. Our results indicate that periods of slow growth in the tree ring record matched periods of drought in the North American Pacific Northwest. Such water limiting conditions are likely caused by oscillatory patterns in the Pacific Ocean sea surface temperatures that influence precipitation in the Pacific Northwest. These drought events are likely exacerbated by changes in winter precipitation (snowpack) related to oscillations of the Atlantic Ocean sea surface temperatures, highlighting the ecological effects of both oceans on terrestrial ecosystems. Such relationships could not be easily found by traditional tree-ring analysis that remove some of the low-frequency signal, and therefore we suggest Ensemble Empirical Mode Decomposition as an additional tool to establishing tree growth-climate relationships.