@article{DiekmannAndresBeckeretal.2019, author = {Diekmann, Martin and Andres, Christian and Becker, Thomas and Bennie, Jonathan and Blueml, Volker and Bullock, James M. and Culmsee, Heike and Fanigliulo, Miriam and Hahn, Annett and Heinken, Thilo and Leuschner, Christoph and Luka, Stefanie and Meissner, Justus and M{\"u}ller, Josef and Newton, Adrian and Peppler-Lisbach, Cord and Rosenthal, Gert and van den Berg, Leon J. L. and Vergeer, Philippine and Wesche, Karsten}, title = {Patterns of long-term vegetation change vary between different types of semi-natural grasslands in Western and Central Europe}, series = {Journal of vegetation science}, volume = {30}, journal = {Journal of vegetation science}, number = {2}, publisher = {Wiley}, address = {Hoboken}, issn = {1100-9233}, doi = {10.1111/jvs.12727}, pages = {187 -- 202}, year = {2019}, abstract = {Questions Has plant species richness in semi-natural grasslands changed over recent decades? Do the temporal trends of habitat specialists differ from those of habitat generalists? Has there been a homogenization of the grassland vegetation? Location Different regions in Germany and the UK. Methods We conducted a formal meta-analysis of re-survey vegetation studies of semi-natural grasslands. In total, 23 data sets were compiled, spanning up to 75 years between the surveys, including 13 data sets from wet grasslands, six from dry grasslands and four from other grassland types. Edaphic conditions were assessed using mean Ellenberg indicator values for soil moisture, nitrogen and pH. Changes in species richness and environmental variables were evaluated using response ratios. Results In most wet grasslands, total species richness declined over time, while habitat specialists almost completely vanished. The number of species losses increased with increasing time between the surveys and were associated with a strong decrease in soil moisture and higher soil nutrient contents. Wet grasslands in nature reserves showed no such changes or even opposite trends. In dry grasslands and other grassland types, total species richness did not consistently change, but the number or proportions of habitat specialists declined. There were also considerable changes in species composition, especially in wet grasslands that often have been converted into intensively managed, highly productive meadows or pastures. We did not find a general homogenization of the vegetation in any of the grassland types. Conclusions The results document the widespread deterioration of semi-natural grasslands, especially of those types that can easily be transformed to high production grasslands. The main causes for the loss of grassland specialists are changed management in combination with increased fertilization and nitrogen deposition. Dry grasslands are most resistant to change, but also show a long-term trend towards an increase in more mesotrophic species.}, language = {en} } @article{PlueDeFrenneAcharyaetal.2017, author = {Plue, Jan and De Frenne, Pieter and Acharya, Kamal and Brunet, J{\"o}rg and Chabrerie, Olivier and Decocq, Guillaume and Diekmann, Martin and Graae, Bente J. and Heinken, Thilo and Hermy, Martin and Kolb, Annette and Lemke, Isgard and Liira, Jaan and Naaf, Tobias and Verheyen, Kris and Wulf, Monika and Cousins, Sara A. O.}, title = {Where does the community start, and where does it end?}, series = {Journal of vegetation science}, volume = {28}, journal = {Journal of vegetation science}, number = {2}, publisher = {Wiley}, address = {Hoboken}, issn = {1100-9233}, doi = {10.1111/jvs.12493}, pages = {424 -- 435}, year = {2017}, abstract = {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.}, language = {en} } @article{DeLombaerdeVerheyenPerringetal.2018, author = {De Lombaerde, Emiel and Verheyen, Kris and Perring, Michael P. and Bernhardt-Roemermann, Markus and Van Calster, Hans and Brunet, Jorg and Chudomelova, Marketa and Decocq, Guillaume and Diekmann, Martin and Durak, Tomasz and Hedl, Radim and Heinken, Thilo and Hommel, Patrick and Jaroszewicz, Bogdan and Kopecky, Martin and Lenoir, Jonathan and Macek, Martin and M{\´a}liš, František and Mitchell, Fraser J. G. and Naaf, Tobias and Newman, Miles and Petř{\´i}k, Petr and Reczyńska, Kamila and Schmidt, Wolfgang and Swierkosz, Krzysztof and Vild, Ondrej and Wulf, Monika and Baetena, Lander}, title = {Responses of competitive understorey species to spatial environmental gradients inaccurately explain temporal changes}, series = {Basic and applied ecology : Journal of the Gesellschaft f{\"u}r {\"O}kologie}, volume = {30}, journal = {Basic and applied ecology : Journal of the Gesellschaft f{\"u}r {\"O}kologie}, publisher = {Elsevier GMBH}, address = {M{\"u}nchen}, issn = {1439-1791}, doi = {10.1016/j.baae.2018.05.013}, pages = {52 -- 64}, year = {2018}, abstract = {Understorey plant communities play a key role in the functioning of forest ecosystems. Under favourable environmental conditions, competitive understorey species may develop high abundances and influence important ecosystem processes such as tree regeneration. Thus, understanding and predicting the response of competitive understorey species as a function of changing environmental conditions is important for forest managers. In the absence of sufficient temporal data to quantify actual vegetation changes, space-for-time (SFT) substitution is often used, i.e. studies that use environmental gradients across space to infer vegetation responses to environmental change over time. Here we assess the validity of such SFT approaches and analysed 36 resurvey studies from ancient forests with low levels of recent disturbances across temperate Europe to assess how six competitive understorey plant species respond to gradients of overstorey cover, soil conditions, atmospheric N deposition and climatic conditions over space and time. The combination of historical and contemporary surveys allows (i) to test if observed contemporary patterns across space are consistent at the time of the historical survey, and, crucially, (ii) to assess whether changes in abundance over time given recorded environmental change match expectations from patterns recorded along environmental gradients in space. We found consistent spatial relationships at the two periods: local variation in soil variables and overstorey cover were the best predictors of individual species' cover while interregional variation in coarse-scale variables, i.e. N deposition and climate, was less important. However, we found that our SFT approach could not accurately explain the large variation in abundance changes over time. We thus recommend to be cautious when using SFT substitution to infer species responses to temporal changes.}, language = {en} } @article{PerringBernhardtRoemermannBaetenetal.2018, author = {Perring, Michael P. and Bernhardt-Roemermann, Markus and Baeten, Lander and Midolo, Gabriele and Blondeel, Haben and Depauw, Leen and Landuyt, Dries and Maes, Sybryn L. and De Lombaerde, Emiel and Caron, Maria Mercedes and Vellend, Mark and Brunet, Joerg and Chudomelova, Marketa and Decocq, Guillaume and Diekmann, Martin and Dirnboeck, Thomas and Doerfler, Inken and Durak, Tomasz and De Frenne, Pieter and Gilliam, Frank S. and Hedl, Radim and Heinken, Thilo and Hommel, Patrick and Jaroszewicz, Bogdan and Kirby, Keith J. and Kopecky, Martin and Lenoir, Jonathan and Li, Daijiang and Malis, Frantisek and Mitchell, Fraser J. G. and Naaf, Tobias and Newman, Miles and Petrik, Petr and Reczynska, Kamila and Schmidt, Wolfgang and Standovar, Tibor and Swierkosz, Krzysztof and Van Calster, Hans and Vild, Ondrej and Wagner, Eva Rosa and Wulf, Monika and Verheyen, Kris}, title = {Global environmental change effects on plant community composition trajectories depend upon management legacies}, series = {Global change biology}, volume = {24}, journal = {Global change biology}, number = {4}, publisher = {Wiley}, address = {Hoboken}, issn = {1354-1013}, doi = {10.1111/gcb.14030}, pages = {1722 -- 1740}, year = {2018}, abstract = {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.}, language = {en} } @article{VannesteValdesVerheyenetal.2018, author = {Vanneste, Thomas and Valdes, Alicia and Verheyen, Kris and Perring, Michael P. and Bernhardt-Roemermann, Markus and Andrieu, Emilie and Brunet, Jorg and Cousins, Sara A. O. and Deconchat, Marc and De Smedt, Pallieter and Diekmann, Martin and Ehrmann, Steffen and Heinken, Thilo and Hermy, Martin and Kolb, Annette and Lenoir, Jonathan and Liira, Jaan and Naaf, Tobias and Paal, Taavi and Wulf, Monika and Decocq, Guillaume and De Frenne, Pieter}, title = {Functional trait variation of forest understorey plant communities across Europe}, series = {Basic and applied ecology : Journal of the Gesellschaft f{\"u}r {\"O}kologie}, volume = {34}, journal = {Basic and applied ecology : Journal of the Gesellschaft f{\"u}r {\"O}kologie}, publisher = {Elsevier GmbH}, address = {M{\"u}nchen}, issn = {1439-1791}, doi = {10.1016/j.baae.2018.09.004}, pages = {1 -- 14}, year = {2018}, abstract = {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.}, language = {en} } @article{deFrenneGraaeKolbetal.2010, author = {de Frenne, Pieter and Graae, Bente Jessen and Kolb, Annette and Brunet, J{\"o}rg and Chabrerie, Olivier and Cousins, Sara A. O. and Decocq, Guillaume and Dhondt, Rob and Diekmann, Martin and Eriksson, Olof and Heinken, Thilo and Hermy, Martin and J{\"o}gar, uelle and Saguez, Robert and Shevtsova, Anna and Stanton, Sharon and Zindel, Renate and Zobel, Martin and Verheyen, Kris}, title = {Significant effects of temperature on the reproductive output of the forest herb Anemone nemorosa L.}, issn = {0378-1127}, doi = {10.1016/j.foreco.2009.04.038}, year = {2010}, abstract = {Climate warming is already influencing plant migration in different parts of the world. Numerous models have been developed to forecast future plant distributions. Few studies, however, have investigated the potential effect of warming on the reproductive output of plants. Understorey forest herbs in particular, have received little attention in the debate on climate change impacts. This study focuses on the effect of temperature on sexual reproductive output (number of seeds, seed mass, germination percentage and seedling mass) of Anemone nemorosa L., a model species for slow colonizing herbaceous forest plants. We sampled seeds of A. nemorosa in populations along a 2400 km latitudinal gradient from northern France to northern Sweden during three growing seasons (2005,2006 and 2008). This study design allowed us to isolate the effects of accumulated temperature (Growing Degree Hours; GDH) from latitude and the local abiotic and biotic environment. Germination and seed sowing trials were performed in incubators, a greenhouse and under field conditions in a forest. Finally, we disentangled correlations between the different reproductive traits of A. nemorosa along the latitudinal gradient. We found a clear positive relationship between accumulated temperature and seed and seedling traits: reproductive output of A. nemorosa improved with increasing GDH along the latitudinal gradient. Seed mass and seedling mass, for instance, increased by 9.7\% and 10.4\%, respectively, for every 1000 degrees C h increase in GDH. We also derived strong correlations between several seed and seedling traits both under field conditions and in incubators. Our results indicate that seed mass, incubator-based germination percentage (Germ\%(Inc)) and the output of germinable seeds (product of number of seeds and Germ\%(Inc) divided by 100) from plants grown along a latitudinal gradient (i.e. at different temperature regimes) provide valuable proxies to parameterize key population processes in models. We conclude that (1) climate warming may have a pronounced positive impact on sexual reproduction of A. nemorosa and (2) climate models forecasting plant distributions would benefit from including the temperature sensitivity of key seed traits and population processes.}, language = {en} } @article{PlueDeFrenneAcharyaetal.2013, author = {Plue, Jan and De Frenne, Pieter and Acharya, Kamal P. and Brunet, Jorg and Chabrerie, Olivier and Decocq, Guillaume and Diekmann, Martin and Graae, Bente J. and Heinken, Thilo and Hermy, Martin and Kolb, Annette and Lemke, Isgard and Liira, Jaan and Naaf, Tobias and Shevtsova, Anna and Verheyen, Kris and Wulf, Monika and Cousins, Sara A. O.}, title = {Climatic control of forest herb seed banks along a latitudinal gradient}, series = {Global ecology and biogeography : a journal of macroecology}, volume = {22}, journal = {Global ecology and biogeography : a journal of macroecology}, number = {10}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {1466-822X}, doi = {10.1111/geb.12068}, pages = {1106 -- 1117}, year = {2013}, abstract = {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.}, language = {en} } @article{deFrenneKolbVerheyenetal.2009, author = {de Frenne, Pieter and Kolb, Annette and Verheyen, Kris and Brunet, Johanne and Chabrerie, Olivier and Decocq, Guillaume and Diekmann, Martin and Eriksson, Ove and Heinken, Thilo and Hermy, Martin and J{\~o}gar, {\"U}lle and Stanton, Sara and Quataert, Paul and Zindel, Renate and Zobel, Martin and Graae, Bente Jessen}, title = {Unravelling the effects of temperature, latitude and local environment on the reproduction of forest herbs}, issn = {1466-822X}, doi = {10.1111/j.1466-8238.2009.00487.x}, year = {2009}, abstract = {Aim To investigate the effect of temperature, latitude and local environment on the reproductive traits of widespread perennial forest herbs to better understand the potential impacts of rising temperatures on their population dynamics and colonization capacities. Location Six regions along a latitudinal gradient from France to Sweden. Methods Within each region, we collected data from three to five populations of up to six species. For each species, several variables were recorded in each region (temperature, latitude) and population (local abiotic and biotic environmental variables), and seed production and germination were estimated. Resource investment in reproduction (RIR) was quantified as seed number ¥ seed mass, while germinable seed output (GSO) was expressed as seed number ¥ germination percentage.We performed linear regression and mixed effect models to investigate the effects of temperature (growing degree hours), latitude and local abiotic and biotic environment on RIR and GSO. Results Temperature and latitude explained most of the variation in RIR and GSO for early flowering species with a northerly distribution range edge (Anemone nemorosa, Paris quadrifolia and Oxalis acetosella). Reproduction of the more southerly distributed species (Brachypodium sylvaticum, Circaea lutetiana and Primula elatior), in contrast, was independent of temperature/latitude. In the late summer species, B. sylvaticum and C. lutetiana, variation in RIR and GSO was best explained by local environmental variables, while none of the investigated variables appeared to be related to reproduction in P. elatior. Main conclusions We showed that reproduction of only two early flowering, northerly distributed species was related to temperature. This suggests that the potential reproductive response of forest herbs to climate warming partly depends on their phenology and distribution, but also that the response is to some extent species dependent. These findings should be taken into account when predictions about future shifts in distribution range are made.}, language = {en} } @article{GraaeVerheyenKolbetal.2009, author = {Graae, Bente Jessen and Verheyen, Kris and Kolb, Annette and van der Veken, Sebastian and Heinken, Thilo and Chabrerie, Olivier and Diekmann, Martin and Valtinat, Karin and Zindel, Renate and Karlsson, Elisabeth and Str{\"o}m, Lotta and Decocq, Guillaume and Hermy, Martin and Baskin, Carol C.}, title = {Germination requirements and seed mass of slow- and fast-colonizing temperate forest herbs along a latitudinal gradient}, issn = {1195-6860}, doi = {10.2980/16-2-3234}, year = {2009}, abstract = {Predictions on displacement of suitable habitats due to climate change suggest that plant species with poor colonization ability may be unable to move fast enough to match forecasted climate-induced changes in habitat distribution. However, studies on early Holocene plant migration show fast migration of many plant species that are poor colonizers today. We hypothesize that warmer temperatures during the early Holocene yielded higher seed quality, contributing to explaining the fast migration. We studied how the 3 seed quality variables, seed mass, germinability, and requirements for break of seed dormancy, vary for seeds of 11 forest herb species with varying colonization capacity collected along a 1400-km latitudinal gradient. Within species, seed mass showed a positive correlation with latitude, whereas germinability was more positively correlated with temperature (growing degree hours obtained at time of seed collection). Only slow-colonizing species increased germinability with temperature, whereas only fast-colonizing species increased germinability with latitude. These interactions were only detectable when analyzing germinability of the seeds, even though this trait and seed mass were correlated. The requirement for dormancy break did not correlate with latitude or temperature. The results indicate that seed development of slow colonizers may be favoured by a warmer climate, which in turn may be important for their migration capacity.}, language = {en} } @article{CaronDeFrenneBrunetetal.2015, author = {Caron, Maria Mercedes and De Frenne, Pieter and Brunet, J{\"o}rg and Chabrerie, Olivier and Cousins, Sara A. O. and Decocq, Guillaume and Diekmann, Martin and Graae, Bente Jessen and Heinken, Thilo and Kolb, Annette and Lenoir, Jonathan and Naaf, Tobias and Plue, Jan and Selvi, Federico and Wulf, Monika and Verheyen, Kris}, title = {Divergent regeneration responses of two closely related tree species to direct abiotic and indirect biotic effects of climate change}, series = {Forest ecology and management}, volume = {342}, journal = {Forest ecology and management}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0378-1127}, doi = {10.1016/j.foreco.2015.01.003}, pages = {21 -- 29}, year = {2015}, abstract = {Changing temperature and precipitation can strongly influence plant reproduction. However, also biotic interactions might indirectly affect the reproduction and recruitment success of plants in the context of climate change. Information about the interactive effects of changes in abiotic and biotic factors is essential, but still largely lacking, to better understand the potential effects of a changing climate on plant populations. Here we analyze the regeneration from seeds of Acer platanoides and Acer pseudoplatanus, two currently secondary forest tree species from seven regions along a 2200 km-wide latitudinal gradient in Europe. We assessed the germination, seedling survival and growth during two years in a common garden experiment where temperature, precipitation and competition with the understory vegetation were manipulated. A. platanoides was more sensitive to changes in biotic conditions while A. pseudoplatanus was affected by both abiotic and biotic changes. In general, competition reduced (in A. platanoides) and warming enhanced (in A. pseudoplatanus) germination and survival, respectively. Reduced competition strongly increased the growth of A. platanoides seedlings. Seedling responses were independent of the conditions experienced by the mother tree during seed production and maturation. Our results indicate that, due to the negative effects of competition on the regeneration of A. platanoides, it is likely that under stronger competition (projected under future climatic conditions) this species will be negatively affected in terms of germination, survival and seedling biomass. Climate-change experiments including both abiotic and biotic factors constitute a key step forward to better understand the response of tree species' regeneration to climate change. (C) 2015 Elsevier B.V. All rights reserved.}, language = {en} }