Study of the vegetation series of Cuenca de Pamplona-Valdizarbe (Navarre-NE Spain): interest of their mapping and application

Se estudian las series y subseries de vegetación de 77.817 ha del centro de Navarra, para su cartografía a escala 1:25.000. Las series y subseries son indicadoras de las características ecológicas del territorio y complementan la información climática disponible. Se han descrito ocho series de vegetación, dos geoseries y dos complejos de vegetación. Las series climatófilas comprenden 28 faciaciones, reconocidas mediante las comunidades vegetales que las integran. La distinción de las faciaciones no sólo está asociada a factores climáticos, sino también a factores geomorfológicos, litológicos, edáficos e históricos. Estos últimos factores permiten reconocer patrones complejos a escalas de detalle, superpuestos a los que reflejan los factores climáticos, evidentes a escalas más reducidas. El estudio se enmarca en un proyecto que pretende definir la potencialidad del territorio para diferentes usos y elaborar modelos de evaluación de tierras en Navarra utilizando las unidades cartográficas reconocidas.The vegetation series and subseries of 77,817 ha of Central Navarre are studied to be used as mapping units of a vegetation series map at scale 1:25,000. The series and subseries are indicators of the land environmental features and may be useful to complete the available climatic data. Eight vegetation series, two geoseries and two vegetation complexes have been described. Climatophilous series include 28 subseries defined by the different plant communities that form each one. While vegetation series show clearly climatic patterns when studied at small scales, at detailed scales the vegetation patterns show also the effects of landforms, lithology, soils and history. This study is part of a project that is intended to assess land suitability for different uses and to work out land evaluation models in Navarre based upon the recognized mapping units

ρ-MtreeRing: A graphical user interface for X-ray microdensity analysis

Producción CientíficaWood microdensitometry provides an integrated measurement of inter and intra-annual changes in wood anatomy and lignification. Although it can be acquired through a wide array of techniques, X-ray-based techniques are still the standard. Conversion of a grayscale X-ray image to density and annual ring boundaries delimitation is performed through image analysis software. Proprietary software has dominated these applications, albeit Free Open Source Software (FOSS) has been developed recently. We present ρ-MtreeRing, a user-friendly FOSS that streamlines the entire microdensitometry analysis process through a graphical user interface based on Shiny R Software without any programming knowledge. We compared the results of this program with the most widely used commercial software (WinDendro), showing the validity of the results. ρ-MtreeRing can be personalized and developed by the microdensitometry research community.Junta de Castilla y León (VA171P20)Ministerio de Ciencia e Innovación y Ministerio de Universidades grant number CGL2017-87309-P (MGH PRE2018-084106) and project PROWARM (PID2020-118444GA-I00)Universidad Politécnica de Madrid (through Project RP200060107)Centro de Recursos Hídricos para la Agricultura y la Minería (ANID/FONDAP/15130015

How to build and install your own CaptuRING

Producción CientíficaCaptuRING is a reliable and affordable tool to transform tree-ring samples into digital images combining open source software and do-it-yourself philosophies. A Raspberry Pi runs the system through an Arduino board that controls the wood sample movement across a linear screw at the time that a digital camera takes sequential high resolution (>4500 dpi) images from a wood sample. Here, we present three video tutorials, with English and Spanish subtitles, to construct and install CaptuRING (github.com/CambiumRG/CaptuRING) from scratch. First video tutorial explains the necessary components and how to assemble them to construct the CaptuRING platform, second tutorial covers Arduino board and Raspberry Pi connections, and the third tutorial is devoted to hardware configuration, software installation and CaptuRING use.Ministerio de Ciencia, Innovación y Universidades - Agencia Estatal de Investigación (grants PRE2018-084106 and IJC2019-040571-I ; project PID2020-118444GA-100)Junta de Castilla y Leon (projects IR2020-1-UVA08 and VA171P20)EU LIFE Soria Forest Adapt (project LIFE19 CCA/ES/001181)Caja Rural de Soria - FUNGE-UVa (project 26/04/2022 TCUE 2021-2023

250-Year reconstruction of pollarding events reveals sharp management changes in Iberian ash woodlands

Producción CientíficaTree pollarding was a dominant management strategy of European forests for centuries creating open agroforestry landscapes with important cultural and environmental values. This traditional practice has been widely abandoned in last decades with a subsequent impact in terms of biodiversity and cultural loss. Central Spain hosts the largest and best-preserved area of pollarded narrow-leaved ash (Fraxinus angustifolia Vahl.) woodlands in Europe. The main aim of this research is to obtain rigorous historical records of pollarding frequency to get adequate information for traditional ash management. We used dendrochronological techniques to evaluate temporal changes of pollarding frequency and rotation length. We analysed the stand level synchrony and the effect of land property on pollarding activity from 322 trees growing in eight pollard stands in Central Spain. Pollarding events were unequivocally identified at tree level by a characteristic change in growth pattern. We identified 2426 tree-level pruning events with the first event dated in 1777. Historical pruning recurrence ranged between 5 and 10 years with higher pollarding frequency on private lands. Pruning events within each site were synchronous, suggesting the existence of a rotational schema within each stand. Pruning frequency decreased drastically in the 1970s matching with the depopulation of rural areas and the general abandonment of traditional practices. Pollarding practices have recovered in recent decades although with lower intensity and lacking the synchronic historical patterns. Providing technical and economic support to make this traditional activity profitably would have strong environmental revenue due the multiple ecosystem services provided by pollarded ashes.iuFOR Institute Unit of Excellence" of the University of Valladolid, funded by the Junta de Castilla y León and co-financed by the European Union (ERDF "Europe drives our growth") project (CLU-2019-01)Ministerio de Ciencia e Innovación y Agencia Estatal de Investigación - MCIN/AEI/10.13039/501100011033 project PROWARM (PID2020-118444GA-100),(IJC2019-040571-I),(grant PRE2018-084106)Junta de Castilla y León, projects, (VA171P20) and (IR2020-1-UVA08)Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL

Vertical cliffs harbor millennia‐old junipers in the Canary Islands

Producción CientíficaThe ability of trees to endure for millennia, surpassing human lifetimes, and survive the most destructive human and natural hazards is astonishing. But what is the ecological role of tree longevity? Are old trees more than impressive nature wonders? Can ancient trees become effective genetic reservoirs able to recover bygone ecosystems? Oceanic islands are ideal ecosystems to address these questions, as they have experienced recent and intense human-induced environmental changes. In the Canary Islands in the northeastern Atlantic Ocean, human colonization since the fifth century BCE (Rodríguez-Varela et al., 2017) added logging, fire, and grazing pressure to a territory already experiencing regular volcanic activity. Tenerife Island is the most populated island of the Canary Islands archipelago and harbors the largest subalpine ecosystems in the entire Macaronesian Biogeographic Region. Woodlands in the Tenerife subalpine environment were once formed by the Canary Island juniper (Juniperus cedrus Webb. & Berthel.; hereafter juniper; Machado & Galván, 2012, García-Cervigón et al., 2019), but historical human pressure restricted its distribution to inaccessible spots, away from human activity, such as cliffs. [parte del texto]Comunidad de Madrid, Grant/Award Number: REMEDINAL TE-CM (S2018/EMT-4338)Junta de Castilla y León-Consejería de Educación, Grant/Award Numbers: (VA113G19), (VA171P20) y (IR2020-1-UVA08)Ministerio de Ciencia e Innovación, Grant/Award Numbers: LAUREL (PID2019-109906RA-I00), (PRE2018-084106) and PROWARM (PID2020-118444GA-100)Ministerio de Economía, Industria y Competitividad. Grant/Award Number: (IJC2019-040571-I)Secretaría de Estado de Investigación, Desarrollo e Innovación, Grant/Award Number: spRING (CGL2017-87309-P

Forgotten giants: Robust climate signal in pollarded trees

Producción CientíficaTree ring records are among the most valuable resources to create high-resolution climate reconstructions. Most climate reconstructions are based on old trees growing in inaccessible mountainous areas with low human activity. Therefore, reconstruction of climate conditions in lowlands is usually based on data from distant mountains. Albeit old trees can be common in humanized areas, they are not used for climate reconstructions. Pollarding was a common traditional management in Europe that enabled trees to maintain great vitality for periods exceeding the longevity of unmanaged trees. We evaluate the potential of pollarded deciduous oaks to record past climate signal. We sampled four pollarded woodlands in Central Spain under continental Mediterranean climate. We hypothesized that pollarded trees have a strong response to water availability during current period without pollarding management, but also in the period under traditional management if pruning was asynchronous among trees. Moreover, we hypothesized that if climate is a regional driver of oak secondary growth, chronologies from different woodlands will be correlated. Pollard oaks age exceeded 500 years with a strong response to Standardized Precipitation-Evapotranspiration Index (SPEI) from 9 to 11 months. Climate signal was exceptionally high in three of the sites (r2 = 0.443–0.655) during low management period (1962–2022). The largest fraction of this climate signal (≈70 %) could be retrieved during the traditional management period (1902–1961) in the three sites where pollarding was asynchronous. Chronologies were significantly correlated since the 19th century for all the studied period, highlighting a shared climate forcing. We identified critical points to optimize pollard tree sampling schema. Our results show the enormous potential of pollarded woodlands to reconstruct hydroclimate conditions in the Mediterranean with a fine spatial grain. Studying pollarded trees is an urgent task, since the temporal window to retrieve the valuable information in pollarded trees is closing as these giants collapse and their wood rots.Junta de Castilla y León-Consejería de Educación [IR2020-1-UVA08; VA171P20]EU LIFE Soria Forest Adapt [LIFE19 CCA/ES/001181]Ministerio de Ciencia e Innovación - AEI (IJC2019-040571-I)Ministerio de Ciencia e Innovación - AEI (PRE2018-084106

CaptuRING: A do‐it‐yourself tool for wood sample digitization

Producción CientíficaStandard procedures to obtain high-quality images of wood samples have become a bottleneck in the digitization of dendrochronology. Digitization is currently dominated by flatbed scanners, but the use of these devices is limited by sample length and surface flatness. Although several solutions based on digital photography have been published, they lack effective digitization processes or are too expensive to be widely adopted. Free open-source software and hardware has emerged as an alternative to create research tools that combine reduced costs with high reliability. Here we present CaptuRING, an open-source tool for wood sample digitization combining a do-it-yourself hardware based on Arduino® with a DSLR camera and a free open-source software with an easy-to-use graphical user interface. We compared CaptuRing with image acquisition from a standard flatbed scanner Epson® V750PRO. CaptuRING outperforms scanner image resolution and sharpness, while it removes sample size limitations. Moreover, CaptuRing performs this task in less than half of the time needed by Epson® V750PRO flatbed scanner. CaptuRING emerges as a reliable and low-cost tool to capture high-resolution images of wood samples boosting current digitization processes. The combination of free open software and hardware empowers dendrochronology to advance in wood sample digitization.Junta de Castilla y León, project OUTBREAK (VA171P20) and (IR2020-1-UVA08)Ministerio de Ciencia, Innovación y Universidades, grant number (CGL2017-87309-P) (MGH PRE2018-084106) and project PROWARM (PID2020-118444GA-I00)Universidad Politécnica de Madrid (through Project RP200060107

Tree-ring distinctness, dating potential and climatic sensitivity of laurel forest tree species in Tenerife Island

Producción CientíficaMacaronesian laurel forests are the only remnants of a subtropical palaeoecosystem dominant during the Tertiary in Europe and northern Africa. These biodiverse ecosystems are restricted to cloudy and temperate insular environments in the North Atlantic Ocean. Due to their reduced distribution area, these forests are particularly vulnerable to anthropogenic disturbances and changes in climatic conditions. The assessment of laurel forest trees’ response to climate variation by dendrochronological methods is limited because it was assumed that the lack of marked seasonality would prevent the formation of distinct annual tree rings. The aims of this study were to identify the presence of annual growth rings and to assess the dendrochronological potential of the most representative tree species from laurel forests in Tenerife, Canary Islands. We sampled increment cores from 498 trees of 12 species in two well-preserved forests in Tenerife Island. We evaluated tree-ring boundary distinctness, dating potential, and sensitivity of tree-ring growth to climate and, particularly, to drought occurrence. Eight species showed clear tree-ring boundaries, but synchronic annual tree rings and robust tree-ring chronologies were only obtained for Laurus novocanariensis, Ilex perado subsp. platyphylla, Persea indica and Picconia excelsa, a third of the studied species. Tree-ring width depended on water balance and drought occurrence, showing sharp reductions in growth in the face of decreased water availability, a response that was consistent among species and sites. Inter-annual tree-ring width variation was directly dependent on rainfall input in the humid period, from previous October to current April. The four negative pointer years 1995, 1999, 2008 and 2012 corresponded to severe drought events in the study area. This study gives the first assessment of dendrochronological potential and tree-ring climate sensitivity of tree species from the Tenerife laurel forest, which opens new research avenues for dendroecological studies in Macaronesian laurel forests.Ministerio de Ciencia, Innovación y Universidades (projects PID2019-109906RA-I00, PID2020-118444GA-100 and PID2019-106908RA-I00/AEI/10.13039/501100011033)Ministerio de Ciencia, Innovación y Universidades (predoctoral contract PRE2018-084106)Ministerio de Economía, Industria y Competitividad (project CGL2017-87309-P and postdoctoral grant IJC2019-040571-I)Junta de Castilla y León (projects VA113G19 and IR2020-1-UVA08)Universidad de Valladolid (predoctoral contract 113-2019PREUVA22)Comunidad de Madrid (project S2018/EMT-4338

Disruption of Juniperus thurifera woodland structure in its northwestern geographical range: potential drivers and limiting factors

Enhancement of Juniperus thurifera recruitment and colonisation by oak and pine species has been related at the local level to changes in livestock pressure. We used forest inventory data from Castilla y León Autonomous Region (Central Spain), an area comprising 34% of the world range of J. thurifera, to assess whether this process is occurring at a larger scale. We compared tree composition and density in a set of 659 permanent plots over a 10-year period. Logistic models and redundancy analysis were used to assess the effect on this process of parameters such as livestock pressure, propagule availability and climatic conditions. Between 1992 and 2002, juniper woodlands became denser (1.31% juniper stem year-1) and tree diversity increased due to rapid colonisation by oaks and pines (2.21% occupied plots year-1). In addition, the presence of juniper increased in other types of forests at a moderate rate (0.6% y-1). Thus, we observed both a disruption of the borders between current forest types and a generalised increase in a-diversity of tree species. The seed source was the main factor explaining colonisation rate, suggesting that the pace of colonisation is critically constrained by the spatial configuration of the landscape and the local propagule availability of the colonising species. If the current colonisation trends continue, monospecific juniper woodlands will become very scarce by the end of the twenty-first century.M.A.Z. was supported by grant CGL2008-04503-C03-03 (MCI) and SUM2008-00004-C03.01 (INIA), and V.R. by INIA-Xunta de Galicia and CSIC contracts. Junta de Castilla y León funded this research with project VA069A07.Peer Reviewe