Bogdziewicz M., Espelta J.M., Bonal R. (2019) Tolerance to seed predation mediated by seed size increases at lower latitudes in a Mediterranean oak. Annals of Botany. 123: 707-714.EnllaçDoi: 10.1093/aob/mcy203
Background and Aims: The ability of plants to allocate energy to resistance against herbivores changes with abiotic conditions and thus may vary along geographical clines, with important consequences for plant communities. Seed size is a plant trait potentially influencing plant tolerance to endoparasites, and seed size often varies across latitude. Consequently, plant tolerance to endoparasites may change across geographical clines. Methods: The interaction between Quercus ilex (holm oak) and seed-predating Curculio spp. (weevils) was explored along most of the latitudinal range of Q. ilex. This included quantification of variation in seed size, survival likelihood of infested seeds, multi-infestation of acorns and community composition of Curculio weevils in acorns. Key Results: Larger seeds had a higher probability of surviving weevil attack (i.e. embryo not predated). Southern populations of oak produced on average four times larger seeds than those of northern populations. Consequently, the probability of survival of infested acorns decreased with latitude. The community composition of Curculio varied, with large weevils (C. elephas) dominating in southern populations and small weevils (C. glandium) dominating in northern populations. However, damage tolerance was robust against this turnover in predator functional traits. Furthermore, we did not detect any change in multi-infestation of acorns along the geographical gradient. Conclusions: Quercus ilex tolerance to seed predation by Curculio weevils increases toward the southern end of its distribution. Generally, studies on geographical variation in plant defence against enemies largely ignore seed attributes or they focus on seed physical barriers. Thus, this research suggests another dimension in which geographical trends in plant defences should be considered, i.e. geographical variation in tolerance to seed predators mediated by seed size. © 2018 The Author(s).
Bogdziewicz M., Szymkowiak J., Fernández-Martínez M., Peñuelas J., Espelta J.M. (2019) The effects of local climate on the correlation between weather and seed production differ in two species with contrasting masting habit. Agricultural and Forest Meteorology. 268: 109-115.EnllaçDoi: 10.1016/j.agrformet.2019.01.016
Many plant species present inter-annual cycles of seed production (mast seeding), with synchronized high seed production across populations in some years. Weather is believed to be centrally involved in triggering masting. The links between meteorological conditions and seeding are well-recognized for some species, but in others consistent correlates have not been found. We used a spatially extensive data set of fruit production to test the hypothesis that the influence of weather on seed production is conditioned by local climate and that this influence varies between species with different life history traits. We used two model species. European beech (Fagus sylvatica) that is a flowering masting species, i.e. seed production is determined by variable flower production, and sessile oak (Quercus petraea) that is a fruit-maturation masting species, i.e. seed production is determined by variable ripening of more constant flower production. We predicted that climate should strongly modulate the relationship between meteorological cue and fruit production in Q. petraea, while the relationship should be uniform in F. sylvatica. The influence of meteorological cue on reproduction in fruiting masting species should be strongly conditioned by local climate because the strength of environmental constraint that modulates the success of flower-to-fruit transition is likely to vary with local climatic conditions. In accordance, the meteorological cuing was consistent in F. sylvatica. In contrast, in Q. petraea the relationship between spring temperature and seed production varied among sites and was stronger in populations at colder sites. The clear difference in meteorological conditioning of seed production between the two studied species suggests the responses of masting plants to weather can be potentially systematized according to their masting habit: i.e. fruiting or flowering. © 2019 Elsevier B.V.
Bruelheide H., Dengler J., Jiménez-Alfaro B., Purschke O., Hennekens S.M., Chytrý M., Pillar V.D., Jansen F., Kattge J., Sandel B., Aubin I., Biurrun I., Field R., Haider S., Jandt U., Lenoir J., Peet R.K., Peyre G., Sabatini F.M., Schmidt M., Schrodt F., Winter M., Aćić S., Agrillo E., Alvarez M., Ambarlı D., Angelini P., Apostolova I., Arfin Khan M.A.S., Arnst E., Attorre F., Baraloto C., Beckmann M., Berg C., Bergeron Y., Bergmeier E., Bjorkman A.D., Bondareva V., Borchardt P., Botta-Dukát Z., Boyle B., Breen A., Brisse H., Byun C., Cabido M.R., Casella L., Cayuela L., Černý T., Chepinoga V., Csiky J., Curran M., Ćušterevska R., Dajić Stevanović Z., De Bie E., de Ruffray P., De Sanctis M., Dimopoulos P., Dressler S., Ejrnæs R., El-Sheikh M.A.E.-R.M., Enquist B., Ewald J., Fagúndez J., Finckh M., Font X., Forey E., Fotiadis G., García-Mijangos I., de Gasper A.L., Golub V., Gutierrez A.G., Hatim M.Z., He T., Higuchi P., Holubová D., Hölzel N., Homeier J., Indreica A., Işık Gürsoy D., Jansen S., Janssen J., Jedrzejek B., Jiroušek M., Jürgens N., Kącki Z., Kavgacı A., Kearsley E., Kessler M., Knollová I., Kolomiychuk V., Korolyuk A., Kozhevnikova M., Kozub Ł., Krstonošić D., Kühl H., Kühn I., Kuzemko A., Küzmič F., Landucci F., Lee M.T., Levesley A., Li C.-F., Liu H., Lopez-Gonzalez G., Lysenko T., Macanović A., Mahdavi P., Manning P., Marcenò C., Martynenko V., Mencuccini M., Minden V., Moeslund J.E., Moretti M., Müller J.V., Munzinger J., Niinemets Ü., Nobis M., Noroozi J., Nowak A., Onyshchenko V., Overbeck G.E., Ozinga W.A., Pauchard A., Pedashenko H., Peñuelas J., Pérez-Haase A., Peterka T., Petřík P., Phillips O.L., Prokhorov V., Rašomavičius V., Revermann R., Rodwell J., Ruprecht E., Rūsiņa S., Samimi C., Schaminée J.H.J., Schmiedel U., Šibík J., Šilc U., Škvorc Ž., Smyth A., Sop T., Sopotlieva D., Sparrow B., Stančić Z., Svenning J.-C., Swacha G., Tang Z., Tsiripidis I., Turtureanu P.D., Uğurlu E., Uogintas D., Valachovič M., Vanselow K.A., Vashenyak Y., Vassilev K., Vélez-Martin E., Venanzoni R., Vibrans A.C., Violle C., Virtanen R., von Wehrden H., Wagner V., Walker D.A., Wana D., Weiher E., Wesche K., Whitfeld T., Willner W., Wiser S., Wohlgemuth T., Yamalov S., Zizka G., Zverev A. (2019) sPlot – A new tool for global vegetation analyses. Journal of Vegetation Science. 30: 161-186.EnllaçDoi: 10.1111/jvs.12710
Aims: Vegetation-plot records provide information on the presence and cover or abundance of plants co-occurring in the same community. Vegetation-plot data are spread across research groups, environmental agencies and biodiversity research centers and, thus, are rarely accessible at continental or global scales. Here we present the sPlot database, which collates vegetation plots worldwide to allow for the exploration of global patterns in taxonomic, functional and phylogenetic diversity at the plant community level. Results: sPlot version 2.1 contains records from 1,121,244 vegetation plots, which comprise 23,586,216 records of plant species and their relative cover or abundance in plots collected worldwide between 1885 and 2015. We complemented the information for each plot by retrieving climate and soil conditions and the biogeographic context (e.g., biomes) from external sources, and by calculating community-weighted means and variances of traits using gap-filled data from the global plant trait database TRY. Moreover, we created a phylogenetic tree for 50,167 out of the 54,519 species identified in the plots. We present the first maps of global patterns of community richness and community-weighted means of key traits. Conclusions: The availability of vegetation plot data in sPlot offers new avenues for vegetation analysis at the global scale. © 2019 International Association for Vegetation Science
Camps D., Villero D., Ruiz-Olmo J., Brotons L. (2019) How can climate change affect the potential distribution of common genet Genetta genetta (Linnaeus 1758) in Europe?. Mammal Research. 64: 175-182.EnllaçDoi: 10.1007/s13364-018-0399-4
The common genet Genetta genetta is a carnivore of African origin introduced in Europe at least 13 centuries ago. Its distribution, located in the southwest of the continent, is chiefly constrained by climatic factors. With this premise, and taking into account the existing climate change projections, our goal was to assess possible changes in climatic suitability for common genet in Europe in the future. The maximum entropy statistical method was used to evaluate the potential effects of two greenhouse gas scenarios-low and high emissions-of an average ensemble of six different global circulation models. Projections showed that a large increase in climatically suitable habitat for common genet in continental Europe is likely in the next decades. In this way, the species range may expand within Europe to the east and north. The fact that the common genet may be favoured in a scenario of temperature increase is compatible with the origin of the species associated with hotter climates in Africa. However, despite these results, bioclimatic models do not represent the complete biotic and ecological niche of the species (e.g. competition, predation or dispersal ability), and a full understanding of potential future expansions should include factors that also determine the presence of the species at finer local scales. Bearing this in mind, we have to interpret our results as a first step towards the potential for species distribution change in the near future, but further work should incorporate environmental variability beyond climate in future projection assessments. © 2018, Mammal Research Institute, Polish Academy of Sciences, Białowieża, Poland.
Carabassa V., Ortiz O., Alcañiz J.M. (2019) RESTOQUARRY: Indicators for self-evaluation of ecological restoration in open-pit mines. Ecological Indicators. 102: 437-445.EnllaçDoi: 10.1016/j.ecolind.2019.03.001
Several methods and criteria to evaluate and assess quarry restoration are available in the scientific literature, but they are very specialized and time consuming. Furthermore, there is a lack of evaluation tools appropriate for technicians involved in these types of activities, such as quarry engineers, restoration managers and quality control supervisors in public administration. The work presented attempts to bridge the gap between scientific knowledge and practical needs by proposing a simplified methodology (RESTOQUARRY protocol), which enables the non-scientific public to evaluate restored areas. This procedure focused on five groups of parameters for zone (homogeneous portions within the whole restored area) evaluation: geotechnical risk, drainage network, erosion and physical degradation, soil quality and vegetation status and functionality. Moreover, three groups of parameters are proposed for area (whole restoration) evaluation: landscape integration, ecological connectivity and fauna, and anthropic impacts. This protocol has been tested in 55 open-pit mines located throughout Catalonia (NE Iberian Peninsula), covering a wide range of Mediterranean climatic conditions and geological substrates. Results indicate that the proposed methodology is suitable for detecting critical parameters that can determine the success of the restoration. © 2019 Elsevier Ltd
Cardil A., Otsu K., Pla M., Silva C.A., Brotons L. (2019) Quantifying pine processionary moth defoliation in a pine-oak mixed forest using unmanned aerial systems and multispectral imagery. PLoS ONE. 14: 0-0.EnllaçDoi: 10.1371/journal.pone.0213027
Pine processionary moth (PPM) feeds on conifer foliage and periodically result in outbreaks leading to large scale defoliation, causing decreased tree growth, vitality and tree reproduction capacity. Multispectral high-resolution imagery acquired from a UAS platform was successfully used to assess pest tree damage at the tree level in a pine-oak mixed forest. We generated point clouds and multispectral orthomosaics from UAS through photogrammetric processes. These were used to automatically delineate individual tree crowns and calculate vegetation indices such as the normalized difference vegetation index (NDVI) and excess green index (ExG) to objectively quantify defoliation of trees previously identified. Overall, our research suggests that UAS imagery and its derived products enable robust estimation of tree crowns with acceptable accuracy and the assessment of tree defoliation by classifying trees along a gradient from completely defoliated to non-defoliated automatically with 81.8% overall accuracy. The promising results presented in this work should inspire further research and applications involving a combination of methods allowing the scaling up of the results on multispectral imagery by integrating satellite remote sensing information in the assessments over large spatial scales. © 2019 Cardil et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Carnicer J., Stefanescu C., Vives-Ingla M., López C., Cortizas S., Wheat C., Vila R., Llusià J., Peñuelas J. (2019) Phenotypic biomarkers of climatic impacts on declining insect populations: A key role for decadal drought, thermal buffering and amplification effects and host plant dynamics. Journal of Animal Ecology. : 0-0.EnllaçDoi: 10.1111/1365-2656.12933
Widespread population declines have been reported for diverse Mediterranean butterflies over the last three decades, and have been significantly associated with increased global change impacts. The specific landscape and climatic drivers of these declines remain uncertain for most declining species. Here, we analyse whether plastic phenotypic traits of a model butterfly species (Pieris napi) perform as reliable biomarkers of vulnerability to extreme temperature impacts in natural populations, showing contrasting trends in thermally exposed and thermally buffered populations. We also examine whether improved descriptions of thermal exposure of insect populations can be achieved by combining multiple information sources (i.e., integrating measurements of habitat thermal buffering, habitat thermal amplification, host plant transpiration, and experimental assessments of thermal death time (TDT), thermal avoidance behaviour (TAB) and thermally induced trait plasticity). These integrative analyses are conducted in two demographically declining and two non-declining populations of P. napi. The results show that plastic phenotypic traits (butterfly body mass and wing size) are reliable biomarkers of population vulnerability to extreme thermal conditions. Butterfly wing size is strongly reduced only in thermally exposed populations during summer drought periods. Laboratory rearing of these populations documented reduced wing size due to significant negative effects of increased temperatures affecting larval growth. We conclude that these thermal biomarkers are indicative of the population vulnerability to increasing global warming impacts, showing contrasting trends in thermally exposed and buffered populations. Thermal effects in host plant microsites significantly differ between populations, with stressful thermal conditions only effectively ameliorated in mid-elevation populations. In lowland populations, we observe a sixfold reduction in vegetation thermal buffering effects, and larval growth occurs in these populations at significantly higher temperatures. Lowland populations show reduced host plant quality (C/N ratio), reduced leaf transpiration rates and complete above-ground plant senescence during the peak of summer drought. Amplified host plant temperatures are observed in open microsites, reaching thermal thresholds that can affect larval survival. Overall, our results suggest that butterfly population vulnerability to long-term drought periods is associated with multiple co-occurring and interrelated ecological factors, including limited vegetation thermal buffering effects at lowland sites, significant drought impacts on host plant transpiration and amplified leaf surface temperature, as well as reduced leaf quality linked to the seasonal advance of plant phenology. Our results also identify multiannual summer droughts affecting larval growing periods as a key driver of the recently reported butterfly population declines in the Mediterranean biome. © 2018 The Authors. Journal of Animal Ecology © 2018 British Ecological Society
De Cáceres M., Coll L., Legendre P., Allen R.B., Wiser S.K., Fortin M.-J., Condit R., Hubbell S. (2019) Trajectory analysis in community ecology. Ecological Monographs. : 0-0.EnllaçDoi: 10.1002/ecm.1350
Ecologists have long been interested in how communities change over time. Addressing questions about community dynamics requires ways of representing and comparing the variety of dynamics observed across space. Until now, most analytical frameworks have been based on the comparison of synchronous observations across sites and between repeated surveys. An alternative perspective considers community dynamics as trajectories in a chosen space of community resemblance and utilizes trajectories as objects to be analyzed and compared using their geometry. While methods that take this second perspective exist, for example to test for particular trajectory shapes, there is a need for formal analytical frameworks that fully develop the potential of this approach. By adapting concepts and procedures used for the analysis of spatial trajectories, we present a framework for describing and comparing community trajectories. A key element of our contribution is the means to assess the geometric resemblance between trajectories, which allows users to describe, quantify, and analyze variation in community dynamics. We illustrate the behavior of our framework using simulated data and two spatiotemporal community data sets differing in the community properties of interest (species composition vs. size distribution of individuals). We conclude by evaluating the advantages and limitations of our community trajectory analysis framework, highlighting its broad domain of application and anticipating potential extensions. © 2019 by the Ecological Society of America
De Cáceres M., Martín-Alcón S., González-Olabarria J.R., Coll L. (2019) A general method for the classification of forest stands using species composition and vertical and horizontal structure. Annals of Forest Science. 76: 0-0.EnllaçDoi: 10.1007/s13595-019-0824-0
Key message: We present a novel approach to define pure- and mixed-forest typologies from the comparison of pairs of forest plots in terms of species identity, diameter, and height of their trees. Context: Forest typologies are useful for many purposes, including forest mapping, assessing habitat quality, studying forest dynamics, or defining sustainable management strategies. Quantitative typologies meant for forestry applications normally focus on horizontal and vertical structure of forest plots as main classification criteria, with species composition often playing a secondary role. The selection of relevant variables is often idiosyncratic and influenced by a priori expectations of the forest types to be distinguished. Aims: We present a general framework to define forest typologies where the dissimilarity between forest stands is assessed using coefficients that integrate the information of species composition with the univariate distribution of tree diameters or heights or the bivariate distribution of tree diameters and heights. Methods: We illustrate our proposal with the classification of forest inventory plots in Catalonia (NE Spain), comparing the results obtained using the bivariate distribution of diameters and heights to those obtained using either tree heights or tree diameters only. Results: The number of subtypes obtained using the tree diameter distribution for the calculation of dissimilarity was often the same as those obtained from the tree height distribution or to those using the bivariate distribution. However, classifications obtained using the three approaches were often different in terms of forest plot membership. Conclusion: The proposed classification framework is particularly suited to define forest typologies from forest inventory data and allows taking advantage of the bivariate distribution of diameters and heights if both variables are measured. It can provide support to the development of typologies in situations where fine-scale variability of topographic, climatic, and legacy management factors leads to fine-scale variation in forest structure and composition, including uneven-aged and mixed stands. © 2019, INRA and Springer-Verlag France SAS, part of Springer Nature.
Duane A., Aquilué N., Canelles Q., Morán-Ordoñez A., De Cáceres M., Brotons L. (2019) Adapting prescribed burns to future climate change in Mediterranean landscapes. Science of the Total Environment. 677: 68-83.EnllaçDoi: 10.1016/j.scitotenv.2019.04.348
Fire regimes are shifting or are expected to do so under global change. Current fire suppression is not able to control all wildfires, and its capability to do so might be compromised under harsher climate conditions. Alternative fire management strategies may allow to counteract predicted fire trends, but we lack quantitative tools to evaluate their potential effectiveness at the landscape scale. Here, we sought to quantify changes in fire regimes induced after the implementation of different fire management strategies. We developed and applied a new version of the model MEDFIRE in Catalonia (Mediterranean region of ~32,000 km 2 in NE Spain). We first projected burnt area from 2016 to 2100 resulting from climate change under the Representative Concentration Pathway 8.5 scenario of HadGEM-CC model and under current fire suppression levels. We then evaluated the impacts of four fire management strategies: ‘Let it burn’, fixed effort of prescribed burning with two different spatial allocations, and adaptive prescribed burning dynamically adjusting efforts according to recent past fires. Results predicted the emergence of novel climates associated with similar barometric configurations to current conditions but with higher temperatures (i.e. hot wind events). These novel climates led to an increase in burnt area, which was partially counteracted by negative fire-vegetation feedbacks. All prescribed burning scenarios decreased the amount of high-intensity fires and extreme fire events. The ‘Let it burn’ strategy, although less costly, was not able to reduce the extent of high-intensity fires. The adaptive prescribed burning scenario resulted in the most cost-efficient strategy. Our results provide quantitative evidence of fire management effectiveness, and bring to light key insights that could guide the design of fire policies fit for future novel climate conditions. We propose adaptive landscape management focused on the reduction of fire negative impacts rather than on the elimination of this disturbance from the system. © 2019 Elsevier B.V.
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