TY - JOUR A1 - Winkler, Eckart A1 - Heinken, Thilo T1 - Spread of an ant-dispersed annual herb : an individual-based simulation study on population development of Melampyrum pratense L. N2 - The paper presents a simulation and parameter-estimation approach for evaluating stochastic patterns of population growth and spread of an annual forest herb, Melampyrum pratense (Orobanchaceae). The survival of a species during large-scale changes in land use and climate will depend, to a considerable extent, on its dispersal and colonisation abilities. Predictions on species migration need a combination of field studies and modelling efforts. Our study on the ability of M. pratense to disperse into so far unoccupied areas is based on experiments in secondary woodland in NE Germany. Experiments started in 1997 at three sites where the species was not yet present, with 300 seeds sown within 1m2. Population development was then recorded until 2001 by mapping of individuals with a resolution of 5 cm. Additional observations considered density dependence of seed production. We designed a spatially explicit individual-based computer simulation model to explain the spatial patterns of population development and to predict future population spread. Besides primary drop of seeds (barochory) it assumed secondary seed transport by ants (myrmecochory) with an exponentially decreasing dispersal tail. An important feature of population-pattern explanation was the simultaneous estimation of both population-growth and dispersal parameters from consistent spatio-temporal data sets. As the simulation model produced stochastic time series and random spatially discrete distributions of individuals we estimated parameters by minimising the expectation of weighted sum of squares. These sums of squares criteria considered population sizes, radial population distributions around the area of origin and distributions of individuals within squares of 25cm×25 cm, the range of density action. Optimal parameter values, together with the precision of the estimates, were obtained from calculating sum of squares in regular grids of parameter values. Our modelling results showed that transport of fractions of seeds by ants over distances of 1-2m was indispensable for explaining the observed population spread that led to distances of at most 8mfrom population origin within 3 years. Projections of population development over four additional years gave a diffusion-like increase of population area without any "outposts". This prediction generated by the simulation model gave a hypothesis which should be revised by additional field observations. Some structural deviations between observations and model output already indicated that for full understanding of population spread the set of dispersal mechanisms assumed in the model may have to be extended by additional features of plant-animal mutualism. Y1 - 2007 UR - http://www.sciencedirect.com/science/journal/03043800 SN - 0304-3800 ER - TY - JOUR A1 - Verheyen, Kris A1 - Baeten, Lander A1 - De Frenne, Pieter A1 - Bernhardt-Römermann, Markus A1 - Brunet, Jorg A1 - Cornelis, Johnny A1 - Decocq, Guillaume A1 - Dierschke, Hartmut A1 - Eriksson, Ove A1 - Hedl, Radim A1 - Heinken, Thilo A1 - Hermy, Martin A1 - Hommel, Patrick A1 - Kirby, Keith J. A1 - Naaf, Tobias A1 - Peterken, George A1 - Petrik, Petr A1 - Pfadenhauer, Joerg A1 - Van Calster, Hans A1 - Walther, Gian-Reto A1 - Wulf, Monika A1 - Verstraeten, Gorik T1 - Driving factors behind the eutrophication signal in understorey plant communities of deciduous temperate forests JF - The journal of ecology N2 - 1. Atmospheric nitrogen (N) deposition is expected to change forest understorey plant community composition and diversity, but results of experimental addition studies and observational studies are not yet conclusive. A shortcoming of observational studies, which are generally based on resurveys or sampling along large deposition gradients, is the occurrence of temporal or spatial confounding factors. 2. We were able to assess the contribution of N deposition versus other ecological drivers on forest understorey plant communities by combining a temporal and spatial approach. Data from 1205 (semi-)permanent vegetation plots taken from 23 rigorously selected understorey resurvey studies along a large deposition gradient across deciduous temperate forest in Europe were compiled and related to various local and regional driving factors, including the rate of atmospheric N deposition, the change in large herbivore densities and the change in canopy cover and composition. 3. Although no directional change in species richness occurred, there was considerable floristic turnover in the understorey plant community and a shift in species composition towards more shade-tolerant and nutrient-demanding species. However, atmospheric N deposition was not important in explaining the observed eutrophication signal. This signal seemed mainly related to a shift towards a denser canopy cover and a changed canopy species composition with a higher share of species with more easily decomposed litter. 4. Synthesis. Our multi-site approach clearly demonstrates that one should be cautious when drawing conclusions about the impact of atmospheric N deposition based on the interpretation of plant community shifts in single sites or regions due to other, concurrent, ecological changes. Even though the effects of chronically increased N deposition on the forest plant communities are apparently obscured by the effects of canopy changes, the accumulated N might still have a significant impact. However, more research is needed to assess whether this N time bomb will indeed explode when canopies will open up again. KW - atmospheric deposition KW - determinants of plant community diversity and structure KW - Ellenberg indicator values KW - forest herbs KW - forest management KW - large herbivores KW - north-western Europe KW - resurveys KW - (semi-)permanent plots Y1 - 2012 U6 - https://doi.org/10.1111/j.1365-2745.2011.01928.x SN - 0022-0477 VL - 100 IS - 2 SP - 352 EP - 365 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Vanneste, Thomas A1 - Valdes, Alicia A1 - Verheyen, Kris A1 - Perring, Michael P. A1 - Bernhardt-Roemermann, Markus A1 - Andrieu, Emilie A1 - Brunet, Jorg A1 - Cousins, Sara A. O. A1 - Deconchat, Marc A1 - De Smedt, Pallieter A1 - Diekmann, Martin A1 - Ehrmann, Steffen A1 - Heinken, Thilo A1 - Hermy, Martin A1 - Kolb, Annette A1 - Lenoir, Jonathan A1 - Liira, Jaan A1 - Naaf, Tobias A1 - Paal, Taavi A1 - Wulf, Monika A1 - Decocq, Guillaume A1 - De Frenne, Pieter T1 - Functional trait variation of forest understorey plant communities across Europe JF - Basic and applied ecology : Journal of the Gesellschaft für Ökologie N2 - Global environmental changes are expected to alter the functional characteristics of understorey herb-layer communities, potentially affecting forest ecosystem functioning. However, little is known about what drives the variability of functional traits in forest understories. Here, we assessed the role of different environmental drivers in shaping the functional trait distribution of understorey herbs in fragmented forests across three spatial scales. We focused on 708 small, deciduous forest patches located in 16 agricultural landscape windows, spanning a 2500-km macroclimatic gradient across the temperate forest biome in Europe. We estimated the relative effect of patch-scale, landscape-scale and macroclimatic variables on the community mean and variation of plant height, specific leaf area and seed mass. Macroclimatic variables (monthly temperature and precipitation extremes) explained the largest proportion of variation in community trait means (on average 77% of the explained variation). In contrast, patch-scale factors dominated in explaining community trait variation (on average 68% of the explained variation). Notably, patch age, size and internal heterogeneity had a positive effect on the community-level variability. Landscape-scale variables explained only a minor part of the variation in both trait distribution properties. The variation explained by shared combinations of the variable groups was generally negligible. These findings highlight the importance of considering multiple spatial scales in predictions of environmental-change effects on the functionality of forest understories. We propose that forest management sustainability could benefit from conserving larger, historically continuous and internally heterogeneous forest patches to maximise ecosystem service diversity in rural landscapes. (C) 2018 Gesellschaft fur Okologie. Published by Elsevier GmbH. All rights reserved. KW - Agricultural landscapes KW - Biogeography KW - Community ecology KW - Forest understorey KW - Functional trait diversity KW - Fragmentation KW - Global environmental change KW - Landscape connectivity KW - Macroclimatic gradient KW - Multi-scale analysis Y1 - 2018 U6 - https://doi.org/10.1016/j.baae.2018.09.004 SN - 1439-1791 SN - 1618-0089 VL - 34 SP - 1 EP - 14 PB - Elsevier GmbH CY - München ER - TY - JOUR A1 - Tischew, Sabine A1 - Dierschke, Hartmut A1 - Schwabe, Angelika A1 - Garve, Eckhard A1 - Heinken, Thilo A1 - Holzel, Norbert A1 - Bergmeier, Erwin A1 - Remy, Dominique A1 - Haerdtle, Werner T1 - Pflanzengesellschaft des Jahres 2019: Die Glatthaferwiese T1 - Plant Community of the Year 2019: Oatgras Meadow JF - Tuexenia : Mitteilungen der Floristisch-Soziologischen Arbeitsgemeinschaft N2 - Um Themen des Schutzes von Pflanzengemeinschaften wirksamer in der breiten Öffentlichkeit zu kommunizieren wird der Vorstand der „Floristisch-Soziologischen Arbeitsgemeinschaft (FlorSoz)“ ab 2019 eine „Pflanzengesellschaft des Jahres“ ausrufen. Damit sollen politische und administrative Entscheidungs- und Umsetzungsprozesse zur Erhaltung der Vielfalt von Ökosystemen und Pflanzengesellschaften in Deutschlands gezielt unterstützt werden. Für das Jahr 2019 wurde die Glatthaferwiese ausgewählt. Sie zählt aktuell zu den durch Artenverarmung und Flächenrückgang besonders bedrohten Pflanzengesellschaften Deutschlands. Es sind deshalb dringend Maßnahmen zum Schutz und zur Wiederherstellung notwendig. Dieser Artikel gibt einen kurzen Überblick zur naturschutzfachlichen Bedeutung von Glatthaferwiesen und deren Ökosystemleistungen sowie zur floristisch-soziologischen Erforschung, zu Ursachen ihres Rückgangs und zu geeigneten Gegenmaßnahmen. N2 - Aiming at a better promotion of topics related to the conservation of ecosystems and plant communities, the board of the Floristisch-Soziologische Arbeitsgemeinschaft (FlorSoz)" has launched the initiative to announce a "Plant Community of the Year". Therewith we hope to raise awareness and stimulate civil society and politics in promoting more efficient conservation strategies. For the forthcoming year, we choose the oatgras meadow as Plant Community of the Year 2019. These lowland hay meadows belong to the most threatened plant communities in Germany. Concepts and schemes aiming at the conservation and restoration of lowland hay meadows are urgently needed. This article provides a short overview of the high nature-conservation value of lowland hay meadows and their ecosystem services as well as of the floristic-phytosociological research, reasons for their sharp decline and appropriate countermeasures. Y1 - 2018 U6 - https://doi.org/10.14471/2018.38.011 SN - 0722-494X IS - 38 SP - 287 EP - 295 PB - Floristisch-Soziologische Arbeitsgemeinschaft CY - Göttingen ER - TY - JOUR A1 - Schöpke, Benito A1 - Heinze, Johannes A1 - Pätzig, Marlene A1 - Heinken, Thilo T1 - Do dispersal traits of wetland plant species explain tolerance against isolation effects in naturally fragmented habitats? JF - Plant ecology : an international journal N2 - The effects of habitat fragmentation and isolation on plant species richness have been verified for a wide range of anthropogenically fragmented habitats, but there is currently little information about their effects in naturally small and isolated habitats. We tested whether habitat area, heterogeneity, and isolation affect the richness of wetland vascular plant species in kettle holes, i.e., small glacially created wetlands, in an agricultural landscape of 1 km(2) in NE Germany. We compared fragmentation effects with those of forest fragments in the same landscape window. Since wetland and forest species might differ in their tolerance to isolation, and because isolation effects on plant species may be trait dependent, we asked which key life history traits might foster differences in isolation tolerance between wetland and forest plants. We recorded the flora and vegetation types in 83 isolated sites that contained 81 kettle holes and 25 forest fragments. Overall, the number of wetland species increased with increasing area and heterogeneity, i.e., the number of vegetation types, while area was not a surrogate for heterogeneity in these naturally fragmented systems. Isolation did not influence the number of wetland species but decreased the number of forest species. We also found that seeds of wetland species were on average lighter, more persistent and better adapted to epizoochory, e.g., by waterfowl, than seeds of forest species. Therefore, we suggest that wetland species are more tolerant to isolation than forest species due to their higher dispersal potential in space and time, which may counterbalance the negative effects of isolation. KW - Forest species KW - Habitat fragmentation KW - Isolation KW - Kettle holes KW - Life history traits KW - Wetland species Y1 - 2019 U6 - https://doi.org/10.1007/s11258-019-00955-8 SN - 1385-0237 SN - 1573-5052 VL - 220 IS - 9 SP - 801 EP - 815 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Schwarzer, Christian A1 - Heinken, Thilo A1 - Luthardt, Vera A1 - Joshi, Jasmin Radha T1 - Latitudinal shifts in species interactions interfere with resistance of southern but not of northern bog-plant communities to experimental climate change JF - The journal of ecology N2 - The persistence of species under changed climatic conditions depends on adaptations and plastic responses to these conditions and on interactions with their local plant community resulting in direct and indirect effects of changed climatic conditions. Populations at species' range margins may be especially crucial in containing a gene pool comprising adaptations to extreme climatic conditions. Many species of northern European bog ecosystems reach their southern lowland range limit in central Europe. In a common-garden experiment, we experimentally assessed the impact of projected climatic changes on five bog-plant species (including peat moss Sphagnum magellanicum) sampled along a latitudinal gradient of 1400km from Scandinavia to the marginal lowland populations in Germany. Populations were cultivated in monocultures and in experimental communities composed of all five species from their local community, and exposed to five combinations of three climate treatments (warming, fluctuating water-tables, fertilization) in a southern common garden. Whereas most monocultures showed a decreasing biomass production from southern to northern origins under southern environmental conditions, in the experimental mixed-species communities, an increasing biomass production towards northern communities was observed together with a shift in interspecific interactions along the latitudinal gradient. While negative dominance effects prevailed in southern communities, higher net biodiversity effects were observed in northern subarctic communities. The combined effects of climate treatments increased biomass production in monocultures of most origins. In communities, however, overall the treatments did not result in significantly changed biomass production. Among individual treatments, water-table fluctuations caused a significant decrease in biomass production, but only in southern communities, indicating higher vulnerability to changed climatic conditions. Here, negative effects of climate treatments on graminoids were not compensated by the slightly increased growth of peat moss that benefited from interspecific interactions only in northern communities.Synthesis. We conclude that shifting interactions within multispecies communities caused pronounced responses to changed climatic conditions in wetland communities of temperate southern marginal, but not of northern subarctic origin. Therefore, future models investigating the impacts of climate change on plant communities should consider geographical variation in species interactions an important factor influencing community responses to changed climatic conditions. KW - additive partitioning of biodiversity effects KW - biodiversity KW - ecosystem services KW - ecosystem stability KW - intraspecific divergence KW - multifactorial environmental change KW - nitrogen deposition KW - northern peatlands KW - Sphagnum magellanicum KW - wetland ecosystems Y1 - 2013 U6 - https://doi.org/10.1111/1365-2745.12158 SN - 0022-0477 SN - 1365-2745 VL - 101 IS - 6 SP - 1484 EP - 1497 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Schwabe, Angelika A1 - Tischew, Sabine A1 - Bergmeier, Erwin A1 - Garve, Eckhard A1 - Härdtle, Werner A1 - Heinken, Thilo A1 - Hölzel, Norbert A1 - Peppler-Lisbach, Cord A1 - Remy, Dominique A1 - Dierschke, Hartmut T1 - Pflanzengesellschaft des Jahres 2020 BT - Borstgrasrasen JF - Tuexenia : Mitteilungen der Floristisch-Soziologischen Arbeitsgemeinschaft N2 - Wie erstmals 2019 wird auch für das Jahr 2020 von der „Floristisch-soziologischen Arbeitsgemeinschaft“ (FlorSoz) für Deutschland die „Pflanzengesellschaft des Jahres“ vorgestellt. Damit soll wiederum für die Öffentlichkeit die Notwendigkeit des Schutzes gefährdeter Pflanzengesellschaften aufgezeigt werden. Für das Jahr 2020 wurden die Borstgrasrasen ausgewählt. Wie alle Pflanzengemeinschaften nährstoffarmer Standorte, sind auch die Borstgrasrasen stark gefährdet und regional sogar unmittelbar vom Aussterben bedroht. Wir konzentrieren uns vor allem auf die Bestände der planaren bis montanen Stufe (Unterverband Violenion caninae: Hundsveilchen-Borstgrasrasen). Die Standorte von Violenion caninae-Gesellschaften werden nicht gedüngt und sind auf extensive Beweidung, z.T. auch auf einschürige Mahd angewiesen. Für Borstgrasrasen bezeichnend sind eine Fülle gefährdeter Pflanzenarten wie z.B. Arnica montana (Arnika) und Antennaria dioica (Zweihäusiges Katzenpfötchen). Bei den Borstgrasrasen spielen für die zunehmend hohe Gefährdung nicht nur Flächenrückgänge durch Nutzungsaufgabe, Aufforstung, Sport- und Freizeitaktivitäten und Überbauung eine Rolle, sondern auch Änderungen der Struktur und Artenzusammensetzung durch direkte Düngung sowie atmogene Stickstoffeinträge sind von Bedeutung. Nährstoffanreicherungen führen zum Verlust der konkurrenzschwachen, gefährdeten Arten zugunsten einiger allgemein verbreiteter, häufig dominanter Gräser sowie konkurrenzkräftiger Kräuter. Wir skizzieren die Bedeutung der Borstgrasrasen als gefährdete Lebensgemeinschaften, geben Hinweise zur floristisch-soziologischen Erforschung und zu weiteren Naturschutz-Aspekten (Rückgang, Erhaltung, Möglichkeiten der Restitution). Ein wirksamer Schutz ist nur bei einem integrativen Naturschutzansatz mit geeigneter Nutzung möglich. N2 - As for the first time in 2019 the ‘Floristisch-soziologische Arbeitsgemeinschaft (FlorSoz)’ intro-duces the ‘Plant Community of the Year 2020’ for Germany. The FlorSoz proposal aims to alert the public that the conservation of endangered plant communities and their biodiversity is essential.For the year 2020 the plant community of mat-grass swards (Nardus stricta grassland) has been selected. Similar to other plant communities on nutrient-poor sites, Nardus grassland is highly endan-gered and in some regions on the brink of extinction. We focus on Nardus grassland of the lowland to montane levels with the characteristic Violenion caninae suballiance (named after Viola canina,the Heath Dog-violet). The sites of Violenion caninae communities are not fertilized and depend on extensive grazing, but there are also mat-grass swards which are mown once a year. Nardus grasslands host many threatened species, e.g., Arnica montana (Arnica) and Antennaria dioica (Mountain Everlasting).The decline of Nardus grassland is not only due to abandonment, afforestation, outdoor activities and construction measures, but also due to changes in the structure and species composition through eutrophication by either direct manuring or by atmospheric nitrogen input. Eutrophication causes local decline or extinction of low-competitive, often endangered species which are replaced by ubiquists, mostly highly competitive species. For management, long-term conservation practices like extensive grazing or cutting once a year are essential. We give an outline of Nardus grassland as an endangered habitat type and summarize its current state of ecological and phytosociological research. In particular we take up the issue of conservation, including the loss of Nardus grasslands and their restoration. Effective conservation depends on an integrative nature-conservation approach, using suitable man-agement practices. Y1 - 2019 U6 - https://doi.org/10.14471/2019.39.017 SN - 0722-494X IS - 39 SP - 287 EP - 308 PB - Floristisch-soziologischen Arbeitsgemeinschaft e.V. CY - Göttingen ER - TY - JOUR A1 - Schulze, Kiowa Alraune A1 - Buchwald, Rainer A1 - Heinken, Thilo T1 - Epizoochory via the hooves - the European bison (Bison bonasus L.) as a dispersal agent of seeds in an open-forest-mosaic JF - Tuexenia : Mitteilungen der Floristisch-Soziologischen Arbeitsgemeinschaft N2 - Large herbivores are significant vectors for the long-distance dispersal of seeds in various habitats, both attached to animals (epizoochory) and via gut passage (endozoochory). The majority of studies on epizoochory have examined dispersal in the fur of domesticated ungulates. Studies on wild ungulates are important to understand dispersal processes in many habitats, but rare due to methodological constraints. We studied epizoochory of seeds by European bison in an open-forest-mosaic (nutrient-poor grassland and heathland, mixed forest) in NW Germany, where bison had been introduced for the purpose of nature conservation. At the study site it was possible to apply a method by which hoof material of free-ranging bison was non-invasively collected. We identified a total of 1082 seeds from 32 plant species in the hoof material. The three most abundant species were Polygonum aviculare, Agrostis capillaris and Betula spp. Seed species originated from various habitat types of the study area, while the majority of seeds derived from trampled areas. Compared to the non-dispersed plant species of the study area, dispersed plant species had a higher seed longevity index, suggesting that many seeds were picked up from the soil seed bank. Epizoochory ranking indices of dispersed seed species, classifying the importance of epizoochory, revealed that transport in the fur may be of minor importance for many species, i.e. epizoochory by the hooves turned out to be negatively correlated to epizoochory in the fur. We conclude that European bison disperses a considerable number of seed species through trampling. Further research should consider epizoochory via the hooves and include integrative approaches to understand the different dispersal mechanisms by ungulates and their long-term synergetic effect on plant communities. KW - diaspore KW - external dispersal KW - large ungulate KW - secondary seed dispersal KW - trampling Y1 - 2014 SN - 0722-494X IS - 34 SP - 131 EP - 144 PB - Floristisch-Soziologische Arbeitsgemeinschaft CY - Göttingen ER - TY - JOUR A1 - Schmidt, Marcus A1 - Fischer, Petra A1 - Günzl, Bettina A1 - Heinken, Thilo A1 - Kelm, Hans-Jürgen A1 - Meyer, Peter A1 - Prüter, Johannes A1 - Waesch, Gunnar T1 - Flechten-Kiefernwälder : Artenvielfalt durch alte Nutzungsformen? Y1 - 2008 SN - 1430-2713 ER - TY - JOUR A1 - Reinecke, Jennifer A1 - Klemm, Gunther A1 - Heinken, Thilo T1 - Vegetation change and homogenization of species composition in temperate nutrient deficient scots pine forests after 45 yr JF - Journal of vegetation science N2 - QuestionDoes eutrophication drive vegetation change in pine forests on nutrient deficient sites and thus lead to the homogenization of understorey species composition? LocationForest area (1600ha) in the Lower Spreewald, Brandenburg, Germany. MethodsResurvey of 77 semi-permanent plots after 45yr, including vascular plants, bryophytes and ground lichens. We applied multidimensional ordination of species composition, dissimilarity indices, mean Ellenberg indicator values and the concept of winner/loser species to identify vegetation change between years. Differential responses along a gradient of nutrient availability were analysed on the basis of initial vegetation type, reflecting topsoil N availability of plots. ResultsSpecies composition changed strongly and overall shifted towards higher N and slightly lower light availability. Differences in vegetation change were related to initial vegetation type, with strongest compositional changes in the oligotrophic forest type, but strongest increase of nitrophilous species in the mesotrophic forest type. Despite an overall increase in species number, species composition was homogenized between study years due to the loss of species (mainly ground lichens) on the most oligotrophic sites. ConclusionsThe response to N enrichment is confounded by canopy closure on the N-richest sites and probably by water limitation on N-poorest sites. The relative importance of atmospheric N deposition in the eutrophication effect is difficult to disentangle from natural humus accumulation after historical litter raking. However, the profound differences in species composition between study years across all forest types suggest that atmospheric N deposition contributes to the eutrophication, which drives understorey vegetation change and biotic homogenization in Central European Scots pine forests on nutrient deficient sites. KW - Eutrophication KW - Litter raking KW - Canopy closure KW - Cryptogams KW - Species diversity Y1 - 2014 U6 - https://doi.org/10.1111/jvs.12069 SN - 1100-9233 SN - 1654-1103 VL - 25 IS - 1 SP - 113 EP - 121 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Reinecke, J. A1 - Wulf, M. A1 - Baeten, Lander A1 - Brunet, J. A1 - Decocq, G. A1 - De Frenne, G. A1 - Diekmann, M. A1 - Graae, B. J. A1 - Heinken, Thilo A1 - Hermy, M. A1 - Jamoneau, A. A1 - Lenoir, J. A1 - Plue, J. A1 - Orczewska, A. A1 - Van Calster, H. A1 - Verheyen, Kris A1 - Naaf, T. T1 - Acido- and neutrophilic temperate forest plants display distinct shifts in ecological pH niche across north-western Europe JF - Ecography : pattern and diversity in ecology ; research papers forum N2 - Ecological niches of organisms vary across geographical space, but niche shift patterns between regions and the underlying mechanisms remain largely unexplored. We studied shifts in the pH niche of 42 temperate forest plant species across a latitudinal gradient from northern France to boreo-nemoral Sweden. We asked 1) whether species restrict their niches with increasing latitude as they reach their northern range margin (environmental constraints); 2) whether species expand their niches with increasing latitude as regional plant species richness decreases (competitive release); and 3) whether species shift their niche position toward more acidic sites with increasing latitude as the relative proportion of acidic soils increases (local adaptation). Based on 1458 vegetation plots and corresponding soil pH values, we modelled species response curves using Huisman-Olff-Fresco models. Four niche measures (width, position, left and right border) were compared among regions by randomization tests. We found that with increasing latitude, neutrophilic species tended to retreat from acidic sites, indicating that these species retreat to more favorable sites when approaching their range margin. Alternatively, these species might benefit from enhanced nitrogen deposition on formerly nutrient-poor, acidic sites in southern regions or lag behind in post-glacial recolonization of potential habitats in northern regions. Most acidophilic species extended their niche toward more base-rich sites with increasing latitude, indicating competitive release from neutrophilic species. Alternatively, acidophilic species might benefit from optimal climatic conditions in the north where some have their core distribution area. Shifts in the niche position suggested that local adaptation is of minor importance. We conclude that shifts in the pH niche of temperate forest plants are the rule, but the directions of the niche shifts and possible explanations vary. Our study demonstrates that differentiating between acidophilic and neutrophilic species is crucial to identify general patterns and underlying mechanisms. Y1 - 2016 U6 - https://doi.org/10.1111/ecog.02051 SN - 0906-7590 SN - 1600-0587 VL - 39 SP - 1164 EP - 1175 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Plue, Jan A1 - De Frenne, Pieter A1 - Acharya, Kamal P. A1 - Brunet, Jorg A1 - Chabrerie, Olivier A1 - Decocq, Guillaume A1 - Diekmann, Martin A1 - Graae, Bente J. A1 - Heinken, Thilo A1 - Hermy, Martin A1 - Kolb, Annette A1 - Lemke, Isgard A1 - Liira, Jaan A1 - Naaf, Tobias A1 - Shevtsova, Anna A1 - Verheyen, Kris A1 - Wulf, Monika A1 - Cousins, Sara A. O. T1 - Climatic control of forest herb seed banks along a latitudinal gradient JF - Global ecology and biogeography : a journal of macroecology N2 - Aim Seed banks are central to the regeneration strategy of many plant species. Any factor altering seed bank density thus affects plant regeneration and population dynamics. Although seed banks are dynamic entities controlled by multiple environmental drivers, climatic factors are the most comprehensive, but still poorly understood. This study investigates how climatic variation structures seed production and resulting seed bank patterns. Location Temperate forests along a 1900km latitudinal gradient in north-western (NW) Europe. Methods Seed production and seed bank density were quantified in 153 plots along the gradient for four forest herbs with different seed longevity: Geum urbanum, Milium effusum, Poa nemoralis and Stachys sylvatica. We tested the importance of climatic and local environmental factors in shaping seed production and seed bank density. Results Seed production was determined by population size, and not by climatic factors. G.urbanum and M.effusum seed bank density declined with decreasing temperature (growing degree days) and/or increasing temperature range (maximum-minimum temperature). P.nemoralis and S.sylvatica seed bank density were limited by population size and not by climatic variables. Seed bank density was also influenced by other, local environmental factors such as soil pH or light availability. Different seed bank patterns emerged due to differential seed longevities. Species with long-lived seeds maintained constant seed bank densities by counteracting the reduced chance of regular years with high seed production at colder northern latitudes. Main conclusions Seed bank patterns show clear interspecific variation in response to climate across the distribution range. Not all seed banking species may be as well equipped to buffer climate change via their seed bank, notably in short-term persistent species. Since the buffering capacity of seed banks is key to species persistence, these results provide crucial information to advance climatic change predictions on range shifts, community and biodiversity responses. KW - Climate change KW - interspecific variation KW - plant-climate interaction KW - seed longevity KW - seed production KW - temperate deciduous forest KW - temperature Y1 - 2013 U6 - https://doi.org/10.1111/geb.12068 SN - 1466-822X SN - 1466-8238 VL - 22 IS - 10 SP - 1106 EP - 1117 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Plue, Jan A1 - De Frenne, Pieter A1 - Acharya, Kamal A1 - Brunet, Jörg A1 - Chabrerie, Olivier A1 - Decocq, Guillaume A1 - Diekmann, Martin A1 - Graae, Bente J. A1 - Heinken, Thilo A1 - Hermy, Martin A1 - Kolb, Annette A1 - Lemke, Isgard A1 - Liira, Jaan A1 - Naaf, Tobias A1 - Verheyen, Kris A1 - Wulf, Monika A1 - Cousins, Sara A. O. T1 - Where does the community start, and where does it end? BT - including the seed bank to reassess forest herb layer responses to the environment JF - Journal of vegetation science N2 - QuestionBelow-ground processes are key determinants of above-ground plant population and community dynamics. Still, our understanding of how environmental drivers shape plant communities is mostly based on above-ground diversity patterns, bypassing below-ground plant diversity stored in seed banks. As seed banks may shape above-ground plant communities, we question whether concurrently analysing the above- and below-ground species assemblages may potentially enhance our understanding of community responses to environmental variation. LocationTemperate deciduous forests along a 2000km latitudinal gradient in NW Europe. MethodsHerb layer, seed bank and local environmental data including soil pH, canopy cover, forest cover continuity and time since last canopy disturbance were collected in 129 temperate deciduous forest plots. We quantified herb layer and seed bank diversity per plot and evaluated how environmental variation structured community diversity in the herb layer, seed bank and the combined herb layer-seed bank community. ResultsSeed banks consistently held more plant species than the herb layer. How local plot diversity was partitioned across the herb layer and seed bank was mediated by environmental variation in drivers serving as proxies of light availability. The herb layer and seed bank contained an ever smaller and ever larger share of local diversity, respectively, as both canopy cover and time since last canopy disturbance decreased. Species richness and -diversity of the combined herb layer-seed bank community responded distinctly differently compared to the separate assemblages in response to environmental variation in, e.g. forest cover continuity and canopy cover. ConclusionsThe seed bank is a below-ground diversity reservoir of the herbaceous forest community, which interacts with the herb layer, although constrained by environmental variation in e.g. light availability. The herb layer and seed bank co-exist as a single community by means of the so-called storage effect, resulting in distinct responses to environmental variation not necessarily recorded in the individual herb layer or seed bank assemblages. Thus, concurrently analysing above- and below-ground diversity will improve our ecological understanding of how understorey plant communities respond to environmental variation. KW - Above-ground KW - Below-ground KW - Canopy KW - Disturbance KW - Diversity KW - Light availability KW - NWEurope KW - Plant community KW - Species co-existence KW - Storage effect Y1 - 2017 U6 - https://doi.org/10.1111/jvs.12493 SN - 1100-9233 SN - 1654-1103 VL - 28 IS - 2 SP - 424 EP - 435 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Perring, Michael P. A1 - Bernhardt-Roemermann, Markus A1 - Baeten, Lander A1 - Midolo, Gabriele A1 - Blondeel, Haben A1 - Depauw, Leen A1 - Landuyt, Dries A1 - Maes, Sybryn L. A1 - De Lombaerde, Emiel A1 - Caron, Maria Mercedes A1 - Vellend, Mark A1 - Brunet, Joerg A1 - Chudomelova, Marketa A1 - Decocq, Guillaume A1 - Diekmann, Martin A1 - Dirnboeck, Thomas A1 - Doerfler, Inken A1 - Durak, Tomasz A1 - De Frenne, Pieter A1 - Gilliam, Frank S. A1 - Hedl, Radim A1 - Heinken, Thilo A1 - Hommel, Patrick A1 - Jaroszewicz, Bogdan A1 - Kirby, Keith J. A1 - Kopecky, Martin A1 - Lenoir, Jonathan A1 - Li, Daijiang A1 - Malis, Frantisek A1 - Mitchell, Fraser J. G. A1 - Naaf, Tobias A1 - Newman, Miles A1 - Petrik, Petr A1 - Reczynska, Kamila A1 - Schmidt, Wolfgang A1 - Standovar, Tibor A1 - Swierkosz, Krzysztof A1 - Van Calster, Hans A1 - Vild, Ondrej A1 - Wagner, Eva Rosa A1 - Wulf, Monika A1 - Verheyen, Kris T1 - Global environmental change effects on plant community composition trajectories depend upon management legacies JF - Global change biology N2 - The contemporary state of functional traits and species richness in plant communities depends on legacy effects of past disturbances. Whether temporal responses of community properties to current environmental changes are altered by such legacies is, however, unknown. We expect global environmental changes to interact with land-use legacies given different community trajectories initiated by prior management, and subsequent responses to altered resources and conditions. We tested this expectation for species richness and functional traits using 1814 survey-resurvey plot pairs of understorey communities from 40 European temperate forest datasets, syntheses of management transitions since the year 1800, and a trait database. We also examined how plant community indicators of resources and conditions changed in response to management legacies and environmental change. Community trajectories were clearly influenced by interactions between management legacies from over 200 years ago and environmental change. Importantly, higher rates of nitrogen deposition led to increased species richness and plant height in forests managed less intensively in 1800 (i.e., high forests), and to decreases in forests with a more intensive historical management in 1800 (i.e., coppiced forests). There was evidence that these declines in community variables in formerly coppiced forests were ameliorated by increased rates of temperature change between surveys. Responses were generally apparent regardless of sites’ contemporary management classifications, although sometimes the management transition itself, rather than historic or contemporary management types, better explained understorey responses. Main effects of environmental change were rare, although higher rates of precipitation change increased plant height, accompanied by increases in fertility indicator values. Analysis of indicator values suggested the importance of directly characterising resources and conditions to better understand legacy and environmental change effects. Accounting for legacies of past disturbance can reconcile contradictory literature results and appears crucial to anticipating future responses to global environmental change. KW - biodiversity change KW - climate change KW - disturbance regime KW - forestREplot KW - herbaceous layer KW - management intensity KW - nitrogen deposition KW - plant functional traits KW - time lag KW - vegetation resurvey Y1 - 2017 U6 - https://doi.org/10.1111/gcb.14030 SN - 1354-1013 SN - 1365-2486 VL - 24 IS - 4 SP - 1722 EP - 1740 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Pauliuk, Franziska A1 - Müller, Jörg A1 - Heinken, Thilo T1 - Bryophyte dispersal by sheep on dry grassland JF - Nova Hedwigia : Zeitschrift für Kryptogamenkunde N2 - Many bryophytes may depend on epizoochorous dispersal by large mammals for maintaining their populations and colonizing new habitats. On dry grassland we investigated the transport of bryophyte diaspores by sheep, which are known to be effective epizoochorous dispersal vectors of seed plants. Twelve sheep of two breeds were examined by collecting gametophyte fragments from their fleece and hooves. Furthermore, microscopic diaspores from the soil adhering to the hooves were grown in a greenhouse. Species frequency and composition were compared to bryophyte vegetation on the pasture. Considerable amounts of unspecialized gametophyte fragments from 16 moss species, 40% of the species growing on the pasture, were transported by sheep, especially on the belly and the tail. Additionally, we provide first evidence of epizoochorous dispersal of thallus fragments from fruticose lichens. Sheep breeds differed in species spectrum and frequency, i.e. sheep with dense, curly fleece carried more fragments and larger species than those with smooth and fine hair. Among the dispersed bryophytes pleurocarps, certain taxa, sizes (small species) and life forms (mats) were overrepresented compared to the vegetation of the pasture, while large species, acrocarps, wefts and turfs were underrepresented, reflecting fragmentation and adhesion features of the species. In the hooves mostly acrocarpous colonist species were transported. We conclude that sheep are important dispersal vectors with the potential of long-range dispersal for bryophytes, especially for species without sexual reproduction, and that epizoochorous dispersal of microscopic diaspores might be underestimated in its importance so far. KW - Calcareous grassland KW - dispersal of cryptogams KW - epizoochory KW - shoot fragments KW - life history attributes KW - vegetative reproduction Y1 - 2011 U6 - https://doi.org/10.1127/0029-5035/2011/0092-0327 SN - 0029-5035 VL - 92 IS - 3-4 SP - 327 EP - 341 PB - Cramer CY - Stuttgart ER - TY - JOUR A1 - Maes, Sybryn L. A1 - Perring, Michael P. A1 - Vanhellemont, Margot A1 - Depauw, Leen A1 - Van den Bulcke, Jan A1 - Brumelis, Guntis A1 - Brunet, Jorg A1 - Decocq, Guillaume A1 - den Ouden, Jan A1 - Härdtle, Werner A1 - Hedl, Radim A1 - Heinken, Thilo A1 - Heinrichs, Steffi A1 - Jaroszewicz, Bogdan A1 - Kopecký, Martin A1 - Malis, Frantisek A1 - Wulf, Monika A1 - Verheyen, Kris T1 - Environmental drivers interactively affect individual tree growth across temperate European forests JF - Global change biology N2 - Forecasting the growth of tree species to future environmental changes requires abetter understanding of its determinants. Tree growth is known to respond to global‐change drivers such as climate change or atmospheric deposition, as well as to localland‐use drivers such as forest management. Yet, large geographical scale studiesexamining interactive growth responses to multiple global‐change drivers are relativelyscarce and rarely consider management effects. Here, we assessed the interactiveeffects of three global‐change drivers (temperature, precipitation and nitrogen deposi-tion) on individual tree growth of three study species (Quercus robur/petraea, Fagus syl-vatica and Fraxinus excelsior). We sampled trees along spatial environmental gradientsacross Europe and accounted for the effects of management for Quercus. We collectedincrement cores from 267 trees distributed over 151 plots in 19 forest regions andcharacterized their neighbouring environment to take into account potentially confounding factors such as tree size, competition, soil conditions and elevation. Wedemonstrate that growth responds interactively to global‐change drivers, with species ‐specific sensitivities to the combined factors. Simultaneously high levels of precipita-tion and deposition benefited Fraxinus, but negatively affected Quercus’ growth, high-lighting species‐specific interactive tree growth responses to combined drivers. ForFagus, a stronger growth response to higher temperatures was found when precipita-tion was also higher, illustrating the potential negative effects of drought stress underwarming for this species. Furthermore, we show that past forest management canmodulate the effects of changing temperatures on Quercus’ growth; individuals in plotswith a coppicing history showed stronger growth responses to higher temperatures.Overall, our findings highlight how tree growth can be interactively determined by glo-bal‐change drivers, and how these growth responses might be modulated by past for-est management. By showing future growth changes for scenarios of environmentalchange, we stress the importance of considering multiple drivers, including past man-agement and their interactions, when predicting tree growth. KW - basal area increment KW - climate change KW - Fagus KW - Fraxinus KW - historical ecology KW - nitrogen deposition KW - Quercus KW - tree-ring analysis Y1 - 2018 U6 - https://doi.org/10.1111/gcb.14493 SN - 1354-1013 SN - 1365-2486 VL - 25 IS - 1 SP - 201 EP - 217 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Maes, Sybryn L. A1 - Blondeel, Haben A1 - Perring, Michael P. A1 - Depauw, Leen A1 - Brumelis, Guntis A1 - Brunet, Jörg A1 - Decocq, Guillaume A1 - den Ouden, Jan A1 - Haerdtle, Werner A1 - Hedl, Radim A1 - Heinken, Thilo A1 - Heinrichs, Steffi A1 - Jaroszewicz, Bogdan A1 - Kirby, Keith J. A1 - Kopecky, Martin A1 - Malis, Frantisek A1 - Wulf, Monika A1 - Verheyen, Kris T1 - Litter quality, land-use history, and nitrogen deposition effects on topsoil conditions across European temperate deciduous forests JF - Forest ecology and management N2 - Topsoil conditions in temperate forests are influenced by several soil-forming factors, such as canopy composition (e.g. through litter quality), land-use history, atmospheric deposition, and the parent material. Many studies have evaluated the effects of single factors on physicochemical topsoil conditions, but few have assessed the simultaneous effects of multiple drivers. Here, we evaluate the combined effects of litter quality, land-use history (past land cover as well as past forest management), and atmospheric deposition on several physicochemical topsoil conditions of European temperate deciduous forest soils: bulk density, proportion of exchangeable base cations, carbon/nitrogen-ratio (C/N), litter mass, bio-available and total phosphorus, pH(KCI)and soil organic matter. We collected mineral soil and litter layer samples, and measured site characteristics for 190 20 x 20 m European mixed forest plots across gradients of litter quality (derived from the canopy species composition) and atmospheric deposition, and for different categories of past land cover and past forest management. We accounted for the effects of parent material on topsoil conditions by clustering our plots into three soil type groups based on texture and carbonate concentration. We found that litter quality was a stronger driver of topsoil conditions compared to land-use history or atmospheric deposition, while the soil type also affected several topsoil conditions here. Plots with higher litter quality had soils with a higher proportion of exchangeable base cations, and total phosphorus, and lower C/N-ratios and litter mass. Furthermore, the observed litter quality effects on the topsoil were independent from the regional nitrogen deposition or the soil type, although the soil type likely (co)-determined canopy composition and thus litter quality to some extent in the investigated plots. Litter quality effects on topsoil phosphorus concentrations did interact with past land cover, highlighting the need to consider land-use history when evaluating canopy effects on soil conditions. We conclude that forest managers can use the canopy composition as an important tool for influencing topsoil conditions, although soil type remains an important factor to consider. KW - Soil fertility KW - Ancient forest KW - Post-agricultural forest KW - Coppice KW - High forest KW - pH KW - Phosphorus KW - Base cations KW - Nutrient cycling KW - Decomposition Y1 - 2019 U6 - https://doi.org/10.1016/j.foreco.2018.10.056 SN - 0378-1127 SN - 1872-7042 VL - 433 SP - 405 EP - 418 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Lozada Gobilard, Sissi Donna A1 - Stang, Susanne A1 - Pirhofer-Walzl, Karin A1 - Kalettka, Thomas A1 - Heinken, Thilo A1 - Schröder, Boris A1 - Eccard, Jana A1 - Joshi, Jasmin Radha T1 - Environmental filtering predicts plant-community trait distribution and diversity BT - Kettle holes as models of meta-community systems JF - Ecology and evolution N2 - Meta-communities of habitat islands may be essential to maintain biodiversity in anthropogenic landscapes allowing rescue effects in local habitat patches. To understand the species-assembly mechanisms and dynamics of such ecosystems, it is important to test how local plant-community diversity and composition is affected by spatial isolation and hence by dispersal limitation and local environmental conditions acting as filters for local species sorting.We used a system of 46 small wetlands (kettle holes)natural small-scale freshwater habitats rarely considered in nature conservation policiesembedded in an intensively managed agricultural matrix in northern Germany. We compared two types of kettle holes with distinct topographies (flat-sloped, ephemeral, frequently plowed kettle holes vs. steep-sloped, more permanent ones) and determined 254 vascular plant species within these ecosystems, as well as plant functional traits and nearest neighbor distances to other kettle holes.Differences in alpha and beta diversity between steep permanent compared with ephemeral flat kettle holes were mainly explained by species sorting and niche processes and mass effect processes in ephemeral flat kettle holes. The plant-community composition as well as the community trait distribution in terms of life span, breeding system, dispersal ability, and longevity of seed banks significantly differed between the two habitat types. Flat ephemeral kettle holes held a higher percentage of non-perennial plants with a more persistent seed bank, less obligate outbreeders and more species with seed dispersal abilities via animal vectors compared with steep-sloped, more permanent kettle holes that had a higher percentage of wind-dispersed species. In the flat kettle holes, plant-species richness was negatively correlated with the degree of isolation, whereas no such pattern was found for the permanent kettle holes.Synthesis: Environment acts as filter shaping plant diversity (alpha and beta) and plant-community trait distribution between steep permanent compared with ephemeral flat kettle holes supporting species sorting and niche mechanisms as expected, but we identified a mass effect in ephemeral kettle holes only. Flat ephemeral kettle holes can be regarded as meta-ecosystems that strongly depend on seed dispersal and recruitment from a seed bank, whereas neighboring permanent kettle holes have a more stable local species diversity. KW - biodiversity KW - dispersal KW - disturbance KW - landscape diversity KW - life-history traits KW - plant diversity KW - seed bank KW - species assembly KW - wetland vegetation Y1 - 2019 U6 - https://doi.org/10.1002/ece3.4883 SN - 2045-7758 VL - 9 IS - 4 SP - 1898 EP - 1910 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Lozada Gobilard, Sissi Donna A1 - Stang, Susanne A1 - Pirhofer-Walzl, Karin A1 - Kalettka, Thomas A1 - Heinken, Thilo A1 - Schröder, Boris A1 - Eccard, Jana A1 - Jasmin Radha, Jasmin T1 - Environmental filtering predicts plant‐community trait distribution and diversity BT - Kettle holes as models of meta‐community systems JF - Ecology and Evolution N2 - Meta‐communities of habitat islands may be essential to maintain biodiversity in anthropogenic landscapes allowing rescue effects in local habitat patches. To understand the species‐assembly mechanisms and dynamics of such ecosystems, it is important to test how local plant‐community diversity and composition is affected by spatial isolation and hence by dispersal limitation and local environmental conditions acting as filters for local species sorting. We used a system of 46 small wetlands (kettle holes)—natural small‐scale freshwater habitats rarely considered in nature conservation policies—embedded in an intensively managed agricultural matrix in northern Germany. We compared two types of kettle holes with distinct topographies (flatsloped, ephemeral, frequently plowed kettle holes vs. steep‐sloped, more permanent ones) and determined 254 vascular plant species within these ecosystems, as well as plant functional traits and nearest neighbor distances to other kettle holes. Differences in alpha and beta diversity between steep permanent compared with ephemeral flat kettle holes were mainly explained by species sorting and niche processes and mass effect processes in ephemeral flat kettle holes. The plant‐community composition as well as the community trait distribution in terms of life span, breeding system, dispersal ability, and longevity of seed banks significantly differed between the two habitat types. Flat ephemeral kettle holes held a higher percentage of non‐perennial plants with a more persistent seed bank, less obligate outbreeders and more species with seed dispersal abilities via animal vectors compared with steep‐sloped, more permanent kettle holes that had a higher percentage of wind‐dispersed species. In the flat kettle holes, plant‐species richness was negatively correlated with the degree of isolation, whereas no such pattern was found for the permanent kettle holes. Synthesis: Environment acts as filter shaping plant diversity (alpha and beta) and plant‐community trait distribution between steep permanent compared with ephemeral flat kettle holes supporting species sorting and niche mechanisms as expected, but we identified a mass effect in ephemeral kettle holes only. Flat ephemeral kettle holes can be regarded as meta‐ecosystems that strongly depend on seed dispersal and recruitment from a seed bank, whereas neighboring permanent kettle holes have a more stable local species diversity. KW - biodiversity KW - dispersal KW - disturbance KW - landscape diversity KW - life‐history traits KW - plant diversity KW - seed bank KW - species assembly KW - wetland vegetation Y1 - 2019 U6 - https://doi.org/10.1002/ece3.4883 SN - 2045-7758 PB - John Wiley & Sons, Inc. CY - Hoboken ER - TY - JOUR A1 - Liang, Wei A1 - Heinrich, Ingo A1 - Simard, Sonia A1 - Helle, Gerhard A1 - Linan, Isabel Dorado A1 - Heinken, Thilo T1 - Climate signals derived from cell anatomy of Scots pine in NE Germany JF - Tree physiology N2 - Tree-ring chronologies of Pinus sylvestris L. from latitudinal and altitudinal limits of the species distribution have been widely used for climate reconstructions, but there are many sites within the temperate climate zone, as is the case in northeastern Germany, at which there is little evidence of a clear climate signal in the chronologies. In this study, we developed long chronologies of several cell structure variables (e. g., average lumen area and cell wall thickness) from P. sylvestris growing in northeastern Germany and investigated the influence of climate on ring widths and cell structure variables. We found significant correlations between cell structure variables and temperature, and between tree-ring width and relative humidity and vapor pressure, respectively, enabling the development of robust reconstructions from temperate sites that have not yet been realized. Moreover, it has been shown that it may not be necessary to detrend chronologies of cell structure variables and thus low-frequency climate signals may be retrieved from longer cell structure chronologies. The relatively extensive resource of archaeological material of P. sylvestris covering approximately the last millennium may now be useful for climate reconstructions in northeastern Germany and other sites in the temperate climate zone. KW - cell structure KW - dendroclimatology KW - Pinus sylvestris KW - quantitative wood anatomy KW - tree rings Y1 - 2013 U6 - https://doi.org/10.1093/treephys/tpt059 SN - 0829-318X SN - 1758-4469 VL - 33 IS - 8 SP - 833 EP - 844 PB - Oxford Univ. Press CY - Oxford ER -