@article{FischerHeinkenMeyeretal.2009, author = {Fischer, Petra and Heinken, Thilo and Meyer, Peter and Schmidt, Marcus and Waesch, Gunnar}, title = {Zur Abgrenzung und Situation des FFH-Lebensraumtyps "Mitteleurop{\"a}ische Flechten-Kiefernw{\"a}lder" (91TO) in Deutschland}, issn = {0028-0615}, year = {2009}, abstract = {Die in Deutschland gegenw{\"a}rtig durch N{\"a}hrstoffeintr{\"a}ge und ausbleibenden N{\"a}hrstoffentzug stark im R{\"u}ckgang begriffenen Flechten-Kiefernw{\"a}lder werden als Biotoptyp wie auch als Lebensraumtyp "Mitteleurop{\"a}ische Flechten-Kiefernw{\"a}lder" (Code 91T0) diskutiert. Die bisherige, sehr uneinheitliche Differenzierung von Flechten-Kiefernw{\"a}ldern auf der Ebene von Biotoptypen wird dargestellt. Auf der Grundlage neuerer vegetationskundlicher {\"u}bersichten werden Vorschl{\"a}ge f{\"u}r eine einheitliche Abgrenzung des Biotoptyps "Flechten-Kiefernwald" und des Lebensraumtyps 91T0 unterbreitet. Im nieders{\"a}chsischen Naturwaldreservat "Kaarßer Sandberge" (Niedersachsen) wurde die Anwendung des Konzeptes erfolgreich erprobt. Nicht nur hier, sondern auch deutschlandweit wird der R{\"u}ckgang der Erdflechten in den Kieferw{\"a}ldern zugunsten von Drahtschmiele und/ oder pleurokarpen Moosen deutlich. Nach der derzeitigen Definition des Lebensraumtyps 91T0 besteht auf der Grundlage der FFH-Richtlinie nicht f{\"u}r alle Flechten-Kiefernw{\"a}lder eine Chance der Verbesserung. Der Ausschluss von außerhalb des nat{\"u}rlichen Verbreitungsgebietes der Wald-Kiefer gelegenen sowie von durch Aufforstung angepflanzten Best{\"a}nden bringt Probleme mit sich, die diskutiert werden. F{\"u}r den Erhalt und die Wiederherstellung der gr{\"o}ßtenteils nutzungsbedingt entstandenen Flechten-Kiefernw{\"a}lder sind praktikable Pflegemaßnahmen notwendig, die im Rahmen von Streunutzungsversuchen erprobt werden m{\"u}ssen.}, language = {de} } @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{Heinken2008, author = {Heinken, Thilo}, title = {Welche populationsbiologischen und genetischen Konsequenzen hat Habitatfragmentierung f{\"u}r Pflanzen? : Wissenschaftliche Grundlagen f{\"u}r ein Biotopverbundsystem f{\"u}r Pflanzen in Brandenburg}, issn = {0942-9328}, year = {2008}, abstract = {Neben dem Habitatverlust gelten Konsequenzen der Habitatfragmentierung seit den 1990er Jahren als wesentliche Ursache der Gefaehrdung von Pflanzen und stehen damit nun auch im Fokus des botanischen Artenschutzes. Der vorliegende Beitrag gibt einen ueberblick ueber den Stand der populationsbiologischen und genetischen Forschung und versucht abzuschaetzen, welche Bedeutung Habitatfragmentierung und die dadurch entstehenden kleinen, isolierten Populationen auf heimische Pflanzenarten haben koennen. Als wesentliche und offenbar sehr weit verbreitete negative Effekte werden Zufallsereignisse, Randeffekte, Bestaeuberlimitierung, Gendrift und Inzuchtdepression identifiziert. Zusammen mit verringerter Habitatqualitaet durch Eutrophierung, Entwaesserung oder Nutzungsaenderung wirken sie zumeist negativ auf die Fitness der Individuen und Populationen und erhoehen so deren Aussterberisiko. Dieser negative Effekt kleiner Populationen auf die individuelle Fitness wird unabhaengig von der Ursache als Allee-Effekt bezeichnet. Eine durch einen Biotopverbund gefoerderte Metapopulationsdynamik kann das dauerhafte Aussterben von Pflanzenpopulationen verhindern und mindert die negativen genetischen Effekte der Habitatfragmentierung ueber einen erhoehten Genfluss durch Pollen und Samen. Die bisherigen wissenschaftlichen Studien in Mitteleuropa beruhen allerdings in ueberproportionaler Weise auf bestimmten Pflanzenfamilien (Gentianaceae, Primulaceae), Habitaten (Trocken- und Magerrasen, Wirtschaftsgruenland), insekten- und obligat fremdbestaeubten sowie weitgehend auf sexuelle Fortpflanzung angewiesenen Arten, waehrend etwa ueber Grasartige, Ruderalpflanzen, wind- und selbstbestaeubte sowie an vegetative Fortpflanzung angepasste Arten nur wenige Erkenntnisse vorliegen. Gerade diese und Pflanzenarten mit hohem Ausbreitungspotenzial muessen aber nach derzeitigem Wissensstand als weniger sensitiv gegenueber Habitatfragmentierung eingestuft werden. Auf diesen Befunden aufbauend werden fuer die Naturschutzpraxis Biotoptypen hinsichtlich ihrer Sensitivitaet gegenueber Habitatfragmentierung klassifiziert und ein auf biologischen Merkmalen basierender Kriterienkatalog zur Auswahl von Zielarten des Biotopverbunds vorgestellt. Schließlich wird eroertert, was bei Maßnahmen zur Regeneration kleiner bzw. bereits ausgestorbener Populationen zu beachten ist, und es werden allgemeine Folgerungen zur Ausgestaltung eines Biotopverbundskonzepts fuer Pflanzen gezogen.}, language = {de} } @misc{DierschkeHeinken2019, author = {Dierschke, Hartmut and Heinken, Thilo}, title = {Vorwort}, series = {Tuexenia : Mitteilungen der Floristisch-Soziologischen Arbeitsgemeinschaft}, journal = {Tuexenia : Mitteilungen der Floristisch-Soziologischen Arbeitsgemeinschaft}, number = {39}, publisher = {Floristisch-Soziologische Arbeitsgemeinschaft}, address = {G{\"o}ttingen}, issn = {0722-494X}, pages = {7 -- 7}, year = {2019}, language = {de} } @article{GuentherSchmidtQuittetal.2021, author = {G{\"u}nther, Kerstin and Schmidt, Marcus and Quitt, Heinz and Heinken, Thilo}, title = {Ver{\"a}nderungen der Waldvegetation im Elbe-Havelwinkel von 1960 bis 2015}, series = {Tuexenia : Mitteilungen der Floristisch-Soziologischen Arbeitsgemeinschaft}, journal = {Tuexenia : Mitteilungen der Floristisch-Soziologischen Arbeitsgemeinschaft}, number = {41}, publisher = {Floristisch-Soziologische Arbeitsgemeinschaft}, address = {G{\"o}ttingen}, issn = {0722-494X}, doi = {10.14471/2021.41.005}, pages = {53 -- 85}, year = {2021}, abstract = {Forest ecosystems are subject to a variety of influences such as forest management, nitrogen deposition, changes in the groundwater level or the immigration of invasive species. The repetition of historical releves is an important means of documenting the resulting changes in plant communities and determining their main drivers. In 2015, we examined the vegetation change in 140 semi-permanent plots in managed forests in the Elbe valley in the NE German lowlands (Saxony-Anhalt, Brandenburg). The first survey took place from 1956 to 1963. The releves cover an almost uniquely broad spectrum of different site conditions, ranging from wet forests (alluvial, swamp and bog forests of Alnion incanae, Alnion glutinosae and Betulion pubescentis) to acidic mixed oak forests (Quercion roboris) up to acidic, mostly dry pine forests with different nutrient status (Dicrano-Pinion). We analyzed the changes in the vegetation with the help of forest stand data, winner and loser species, alpha- and beta-diversity as well as the Ellenberg indicator values for nitrogen, reaction, moisture and light. In contrast to previous resurvey studies, areas were also taken into account on which a complete change of forest stand had taken place before the second survey. Particularly in the wet forests and acidic forests with a moderately good nutrient supply, changes in the main tree species have been recorded, and many pine stands have been newly established in the meantime. The species richness has decreased overall and in almost all forest types, but the beta-diversity has remained unchanged or has increased. The Ellenberg values indicate a decrease in soil moisture in the wet forests, while the acidic pine forests in particular have become darker, richer in nutrients and more humid. The number of loser species is more than twice as high as that of the winner species, but with different developments in the individual forest types. In particular, the wet forests, the acidic mixed oak forests and the lichen-pine forests have lost most of their characteristic species. The resurvey after more than 50 years shows a different development of the individual forest types. Vegetation changes in the wet forests are mainly due to local groundwater level drawdown and the resulting increased availability of nutrients. The alluvial forests were also strongly influenced by forest interventions. The reasons for the trend towards more humid and more nutrient-rich conditions in formerly dry acidic pine and oak forests are nitrogen depositions and a succession after the abandonment of historical forms of forest use (litter raking, forest pasture). Although the individual forest types have developed differently, eutrophication, falling groundwater levels and silviculture are the most important causes for the changes in vegetation. Silvicultural interventions such as clear cutting and stand conversion with a change of tree species are at the same time the main reason why the vegetation has not been homogenized despite the leveling of the site gradient as measured by the beta-diversity.}, language = {de} } @article{Heinken2008, author = {Heinken, Thilo}, title = {Vegetation und Standort bodensaurer Buchenw{\"a}lder am Arealrand : am Beispiel Mittelbrandenburgs}, issn = {0018-0637}, year = {2008}, abstract = {Different from NW Germany, the northern part of NE Germany and the "Hohe Flaeming" region, central Brandenburg is considered as being largely devoid of natural beech forests because of its subcontinental, dry climate. In the present study the vegetation ecology of beech forests of the region is comprehensively documented for the first time, and they are compared with NW German stands in Lower Saxony. In the study area beech forests are concentrated in the Berlin-Potsdam region along the Havel river lakes which is characterised by relatively high precipitation and a specific land use history. All belong to the Luzulo-Fagetum growing on acid soils. Four subtypes are distinguished according to nutrient availability and soil moisture. The central Brandenburg Luzulo-Fagetum does not markedly deviate from other beech forests in the northern German lowlands with respect to vegetation structure and edaphic subtypes. However, numerous indicator species for humid or moist conditions are less frequent than under atlantic climate conditions in the lowlands of Lower Saxony, a pattern occurring also in other forest communities. On the other hand, nitrogen and disturbance indicators are more frequent in central Brandenburg. As expected, podzolisation of the soils and humus accumulation is lower in beech forests under subcontinental climate, but surprisingly the soils are more sandy and thus drier. However, beech forests are lacking on south-exposed slopes, and they are notably occurring in northern exposition. A combined analysis of distribution patterns and climatic data, postglacial vegetation history and forest use history, and actual rejuvenation dynamics reveals that the present-day beech forests in central Brandenburg have to be considered as near-natural relics, which are currently spreading. The range of potentially natural beech forests is larger than assumed until now, but further on it is not clearly to define.}, language = {de} } @article{ReineckeKlemmHeinken2014, author = {Reinecke, Jennifer and Klemm, Gunther and Heinken, Thilo}, title = {Vegetation change and homogenization of species composition in temperate nutrient deficient scots pine forests after 45 yr}, series = {Journal of vegetation science}, volume = {25}, journal = {Journal of vegetation science}, number = {1}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {1100-9233}, doi = {10.1111/jvs.12069}, pages = {113 -- 121}, year = {2014}, abstract = {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.}, 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{DeFrenneGraaeBrunetetal.2012, author = {De Frenne, Pieter and Graae, Bente J. and Brunet, J{\"o}rg and Shevtsova, Anna and De Schrijver, An and Chabrerie, Olivier and Cousins, Sara A. O. and Decocq, Guillaume and Diekmann, Martin and Hermy, Martin and Heinken, Thilo and Kolb, Annette and Nilsson, Christer and Stanton, Sharon and Verheyen, Kris}, title = {The response of forest plant regeneration to temperature variation along a latitudinal gradient}, series = {Annals of botany}, volume = {109}, journal = {Annals of botany}, number = {5}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {0305-7364}, doi = {10.1093/aob/mcs015}, pages = {1037 -- 1046}, year = {2012}, abstract = {The response of forest herb regeneration from seed to temperature variations across latitudes was experimentally assessed in order to forecast the likely response of understorey community dynamics to climate warming. Seeds of two characteristic forest plants (Anemone nemorosa and Milium effusum) were collected in natural populations along a latitudinal gradient from northern France to northern Sweden and exposed to three temperature regimes in growth chambers (first experiment). To test the importance of local adaptation, reciprocal transplants were also made of adult individuals that originated from the same populations in three common gardens located in southern, central and northern sites along the same gradient, and the resulting seeds were germinated (second experiment). Seedling establishment was quantified by measuring the timing and percentage of seedling emergence, and seedling biomass in both experiments. Spring warming increased emergence rates and seedling growth in the early-flowering forb A. nemorosa. Seedlings of the summer-flowering grass M. effusum originating from northern populations responded more strongly in terms of biomass growth to temperature than southern populations. The above-ground biomass of the seedlings of both species decreased with increasing latitude of origin, irrespective of whether seeds were collected from natural populations or from the common gardens. The emergence percentage decreased with increasing home-away distance in seeds from the transplant experiment, suggesting that the maternal plants were locally adapted. Decreasing seedling emergence and growth were found from the centre to the northern edge of the distribution range for both species. Stronger responses to temperature variation in seedling growth of the grass M. effusum in the north may offer a way to cope with environmental change. The results further suggest that climate warming might differentially affect seedling establishment of understorey plants across their distribution range and thus alter future understorey plant dynamics.}, language = {en} } @article{DeFrenneBrunetShevtsovaetal.2011, author = {De Frenne, Pieter and Brunet, Jorg and Shevtsova, Anna and Kolb, Annette and Graae, Bente J. and Chabrerie, Olivier and Cousins, Sara Ao and Decocq, Guillaume and De Schrijver, An and Diekmann, Martin and Gruwez, Robert and Heinken, Thilo and Hermy, Martin and Nilsson, Christer and Stanton, Sharon and Tack, Wesley and Willaert, Justin and Verheyen, Kris}, title = {Temperature effects on forest herbs assessed by warming and transplant experiments along a latitudinal gradient}, series = {Global change biology}, volume = {17}, journal = {Global change biology}, number = {10}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {1354-1013}, doi = {10.1111/j.1365-2486.2011.02449.x}, pages = {3240 -- 3253}, year = {2011}, abstract = {Slow-colonizing forest understorey plants are probably not able to rapidly adjust their distribution range following large-scale climate change. Therefore, the acclimation potential to climate change within their actual occupied habitats will likely be key for their short-and long-term persistence. We combined transplant experiments along a latitudinal gradient with open-top chambers to assess the effects of temperature on phenology, growth and reproductive performance of multiple populations of slow-colonizing understorey plants, using the spring flowering geophytic forb Anemone nemorosa and the early summer flowering grass Milium effusum as study species. In both species, emergence time and start of flowering clearly advanced with increasing temperatures. Vegetative growth (plant height, aboveground biomass) and reproductive success (seed mass, seed germination and germinable seed output) of A. nemorosa benefited from higher temperatures. Climate warming may thus increase future competitive ability and colonization rates of this species. Apart from the effects on phenology, growth and reproductive performance of M. effusum generally decreased when transplanted southwards (e. g., plant size and number of individuals decreased towards the south) and was probably more limited by light availability in the south. Specific leaf area of both species increased when transplanted southwards, but decreased with open-top chamber installation in A. nemorosa. In general, individuals of both species transplanted at the home site performed best, suggesting local adaptation. We conclude that contrasting understorey plants may display divergent plasticity in response to changing temperatures which may alter future understorey community dynamics.}, language = {en} }