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Farmland bird populations are in a deep crisis across Europe. Agri-environment schemes (AES) were implemented by the European Union to stop and reverse the general decline of biodiversity in agricultural landscapes. In Germany, flower strips are one of the most common AES. Establishing high-quality perennial wildflower strips (WFS) with species-rich native forb mixtures from regional seed propagation is a recent approach, for which the effectiveness for birds has not yet been sufficiently studied. We surveyed breeding birds and vegetation on 40 arable fields with WFS (20 with single and 20 with aggregated WFS) and 20 arable fields lacking WFS as controls across Saxony-Anhalt (Germany). Additionally, vegetation composition, WFS quantity and landscape structure (e.g. distance to nearest woody element) were considered in our analyses. All WFS were established with species-rich native seed mixtures (30 forbs) in agricultural practice as AES. Arable fields with WFS had a higher species richness and territory density of birds than controls, confirming the effectiveness of this AES. A forb-rich vegetation was the main driver promoting birds. Flower strip quantity at the landscape level had positive effects only on bird densities, but also single WFS achieved benefits. A short distance from WFS to woody elements increased total bird species richness. However, the density of farmland birds, which are target species of these AES, were negatively affected by the proximity and proportion of woody elements in the vicinity. The effect of the proportion of non-intensively used open habitats and overall habitat richness was unexpectedly low in the otherwise intensively farmed landscape. Species-rich perennial WFS significantly promoted breeding birds. Successful establishment of WFS, resulting in high-quality habitats, a high flower strip quantity as well as implementation in open landscapes were shown to maximise the effectiveness for restoring declining and AES target farmland birds.

Green roofs are known to mitigate the negative effects of urban consolidation by offering diverse ecosystem functions compared to non-vegetated roofs. However, the support for native biodiversity might be improved by using native plant species. In a mesocosm experiment, we studied the suitability of three commercial green-roof growth substrates for the establishment of 27 native plant species from dry sandy grasslands of northwestern Germany over the course of four years. The substrates were mineral-based, but differed in the layering of organic matter. Total establishment rates reached 44–59% in Year 4, indicating the general suitability of the substrates. During the first weeks after seeding, with light irrigation, the vascular plant cover was greater in the similar substrates Zincolit® Plus (Z) and Zincolit® Plus-Leicht (ZL) with their compost-based organic mulch layers than in the substrate Sedumteppich (ST) with its organic matter evenly admixed with the mineral aggregates. In Years 2 and 3, however, the vascular plant cover was greater in the ST substrate, likely due to the better availability of water and nutrients from the organic matter compared to the dry surface-mulch layer variants Z and ZL. After severe drought events, the decline in plant cover was more pronounced in the ST substrate, likely representing a trade-off between lush growth and a susceptibility to drought. An indicator-species analysis revealed differences in species composition between the ST and Z/ZL substrates. Annual plant species were indicators of the ST substrate. Perennials, such as Thymus pulegioides and Achillea millefolium, were typical of the Z and ZL substrates. In addition to the general suitability of the tested standard substrates for target species establishment, the study indicated that a combination of different layers of substrate components resulted in different vegetation patterns that may have a positive effect on green-roof biodiversity.

Urban greenspace has gained considerable attention during the last decades because of its relevance to wildlife conservation, human welfare, and climate change adaptation. Biodiversity loss and ecosystem degradation worldwide require the formation of new concepts of ecological restoration and rehabilitation aimed at improving ecosystem functions, services, and biodiversity conservation in cities. Although relict sites of natural and semi-natural ecosystems can be found in urban areas, environmental conditions and species composition of most urban ecosystems are highly modified, inducing the development of novel and hybrid ecosystems. A consequence of this ecological novelty is the lack of (semi-) natural reference systems available for defining restoration targets and assessing restoration success in urban areas. This hampers the implementation of ecological restoration in cities. In consideration of these challenges, we present a new conceptual framework that provides guidance and support for urban ecological restoration and rehabilitation by formulating restoration targets for different levels of ecological novelty (i.e., historic, hybrid, and novel ecosystems). To facilitate the restoration and rehabilitation of novel urban ecosystems, we recommend using established species-rich and well-functioning urban ecosystems as reference. Such urban reference systems are likely to be present in many cities. Highlighting their value in comparison to degraded ecosystems can stimulate and guide restoration initiatives. As urban restoration approaches must consider local history and site conditions, as well as citizens’ needs, it may also be advisable to focus the restoration of strongly altered urban ecosystems on select ecosystem functions, services and/or biodiversity values. Ecosystem restoration and rehabilitation in cities can be either relatively inexpensive or costly, but even expensive measures can pay off when they effectively improve ecosystem services such as climate change mitigation or recreation. Successful re‐shaping and re-thinking of urban greenspace by involving citizens and other stakeholders will help to make our cities more sustainable in the future., Basic and Applied Ecology, 52, ISSN:1439-1791, ISSN:1618-0089

Within the frame of the EU Common Agricultural Policy, most countries subsidise the establishment and maintenance of perennial flower strips on arable land within Agri-Environmental Schemes to provide foraging habitats and refuges for wildlife. In a replicated field experiment, we studied the effects of different types of seed mixtures on the establishment and maintenance of perennial flower strips on fertile arable land in the federal state of Saxony-Anhalt, Germany over seven years. The seed mixtures were commonly applied within recent Common Agricultural Policy funding periods: (1) a low-diversity cultivar standard seed mixture (CULTIVAR), (2) a high-diversity cultivar and native plant mixture (MIX), and (3) a high-diversity native plant mixture (WILDFLOWER). All plots were mulched every year in March and at the beginning of August. The low success of CULTIVAR triggered the massive encroachment of spontaneously established perennial grasses. In MIX, too, cultivars have disappeared after the first year. Both wildflower variants were successful in maintaining a high cover of sown perennial native forbs and a high ratio of established sown species, even after seven years. WILDFLOWER always tended to show better values than MIX. Furthermore, spontaneously establishing species began to spread their cover in MIX in the fifth year, with a very strongly increasing tendency, whereas in WILDFLOWER cover of spontaneously immigrating species stayed satisfyingly low. Using native wildflowers to establish perennial wildflower strips was very effective in maintaining high species diversity within the Agri-Environmental Schemes funding period of five years and beyond. WILDFLOWER was especially successful. On the other hand, CULTIVAR failed completely. On fertile soils in regions with rather low yearly precipitation, mulching twice a year supported the maintenance of perennial wildflower strips.

© 2021 The Authors., Aims: Understanding fine-grain diversity patterns across large spatial extents is fundamental for macroecological research and biodiversity conservation. Using the GrassPlot database, we provide benchmarks of fine-grain richness values of Palaearctic open habitats for vascular plants, bryophytes, lichens and complete vegetation (i.e., the sum of the former three groups). Location: Palaearctic biogeographic realm. Methods: We used 126,524 plots of eight standard grain sizes from the GrassPlot database: 0.0001, 0.001, 0.01, 0.1, 1, 10, 100 and 1,000 m and calculated the mean richness and standard deviations, as well as maximum, minimum, median, and first and third quartiles for each combination of grain size, taxonomic group, biome, region, vegetation type and phytosociological class. Results: Patterns of plant diversity in vegetation types and biomes differ across grain sizes and taxonomic groups. Overall, secondary (mostly semi-natural) grasslands and natural grasslands are the richest vegetation type. The open-access file ”GrassPlot Diversity Benchmarks” and the web tool “GrassPlot Diversity Explorer” are now available online (https://edgg.org/databases/GrasslandDiversityExplorer) and provide more insights into species richness patterns in the Palaearctic open habitats. Conclusions: The GrassPlot Diversity Benchmarks provide high-quality data on species richness in open habitat types across the Palaearctic. These benchmark data can be used in vegetation ecology, macroecology, biodiversity conservation and data quality checking. While the amount of data in the underlying GrassPlot database and their spatial coverage are smaller than in other extensive vegetation-plot databases, species recordings in GrassPlot are on average more complete, making it a valuable complementary data source in macroecology., GrassPlot development has been supported by the Bavarian Research Alliance (BayIntAn_UBT_2017_58), the Eurasian Dry Grassland Group (EDGG) and the International Association for Vegetation Science (IAVS); IB, CorM, JAC, IGM, DGM, MHe, DL and MTo were supported by the Basque Government (IT936‐16); CorM, IAx, MCh, JDa, PD, MHá, ZL, ZPr, EŠ and LT were supported by the Czech Science Foundation (19‐28491X); TR was supported by the Estonian Research Council (PUT1173); RJP was funded by the Strategic Research Programme of the Scottish Government’s Rural and Environmental Science and Analytical Services Division”; SBa was supported by the GINOP‐2.3.2‐15‐2016‐00019 project; GFi was partially supported by the MIUR initiative “Department of excellence” (Law 232/2016)"; BJA was funded by the Spanish Research Agency (grant AEI/ 10.13039/501100011033); AK, VB, IM, DS, IV and DV were supported by the National Research Foundation of Ukraine (2020.01/0140); MP and AH were supported by the Estonian Research Council (PRG874, PRG609), and the European Regional Development Fund (Centre of Excellence EcolChange); Data collection of HCP was funded by FORMAS (Swedish Research Council for Environment, Agricultural Science and Spatial Planning) and The Swedish Institute; JR was supported by the Czech Science Foundation (grant No. 20‐09895S) and the long‐term developmental project of the Czech Academy of Sciences (RVO 67985939); ATRA was funded by the Grant of Excellence Departments, MIUR‐Italy (ARTICOLO 1, COMMI 314 – 337 LEGGE 232/2016); JMA was supported by Carl Tryggers stiftelse för vetenskaplig forskning and Qatar Petroleum; AAli was supported by the Jiangsu Science and Technology Special Project (Grant No. BX2019084), and Metasequoia Faculty Research Startup Funding at Nanjing Forestry University (Grant No. 163010230), and he is currently supported by Hebei University through Faculty Research Startup Funding Program; ZB was supported by the NKFI K 124796 grant; The GLORIA‐ Aragón project of JLBA was funded by the Dirección General de Cambio Climático del Gobierno de Aragón (Spain); MCs and LDem were supported by DG Environment through the European Forum on Nature Conservation and Pastoralism and Barbara Knowles Fund, in collaboration with Pogány‐havas Association, Romania; JDa was partially supported by long‐term research development project no. RVO 67985939 of the Czech Academy of Sciences; BD and OV were supported by the NKFI KH 126476, NKFI KH 130338, NKFI FK 124404 and NKFI FK 135329 grants; BD, OV and AKe were supported by the Bolyai János Scholarship of the Hungarian Academy of Sciences; BE was funded by the Environmental Department of the Tyrolean Federal State Government, the MAB Programme of the Austrian Academy of Science, the Mountain Agriculture Research Unit and the Alpine Research Centre Obergurgl of Innsbruck University. The GLORIA projects of BE were funded by the EU project no. EVK2‐CT‐2000‐00056, the Earth System Sciences Program of the Austrian Academy of Sciences (project MEDIALPS), the Amt für Naturparke, Autonome Provinz Bozen‐Südtirol, the Südtiroler Wissenschaftsfonds and the Tiroler Wissenschaftsfonds; RGG was supported by the Spanish Ministry of Research to sample GLORIA sites in central Spain (CGL 2008‐00901/BOS) and present works by the Autonomous Region of Madrid (REMEDINAL TE‐CM, S2018/EMT‐4338); MJ was supporteLatviaed by Latvia Grant No. 194051; NP and SŠ were partly supported by the Slovenian Research Agency, core fundings P1‐0403 and J7‐1822.

Species dispersal, establishment, and assembly are crucial stages of the life history of plants, and clear understanding of the governing forces and rules that shape species composition in a particular community is vital for successful ecological restoration. In this article, we focus on five aspects of seed dispersal and plant establishment, which should be considered during habitat restoration actions. In the first two sections, we discuss the success of spontaneous dispersal and establishment on restoration based on either spatial dispersal or local seed banks. In the third section, we assess the possibilities of species introduction and assisted dispersal. In the fourth section, we introduce some possibilities for the improvement of establishment success of spontaneously dispersed or introduced species. Finally, we highlight issues influencing long‐term persistence and sustainability of restored habitats, related to the alteration of management type and intensity, climate change, and spread of non‐native species. With the present article, we introduce the special issue entitled “Seed dispersal and soil seed banks – promising sources for ecological restoration” containing 15 papers by 62 authors from 10 countries arranged in the abovementioned five topics.

Reconnection of floodplains to rivers to enhance fluvial dynamics is a favored method of floodplain restoration in Europe. It is believed that the restoration of hydrological conditions of the floodplain facilitates natural dispersal of target species, and hence the reestablishment, of typical plant communities. The aim of our study was to investigate whether floodplain target species could reach restoration sites via hydrochorous dispersal. We analyzed seed inflow from the river and seed dispersal in different sectors of a new watercourse in the Danube floodplain. Seeds were captured using 27 seed traps during three sampling periods of 3 weeks each from summer 2011 to spring 2012. After germination seedlings were identified, we detected a total of almost 39,000 seeds of 176 species, including 80 target species of riparian habitats. We found significant differences between seasons (most seeds in autumn/winter) and between stream sectors. Fewer seeds came in from the Danube (2,800 seeds) than were transported within the floodplain. Several new floodplain target species were detected, which had not been found in the aboveground vegetation or soil seed bank before the start of the restoration. Seeds of nonnative species did not disperse further than approximately 1 km. Our results indicated that hydrochorous seed dispersal from upstream habitats along the new watercourse was important for the establishment of target species and hence for the success of floodplain restoration. Technical water diversion weirs must be traversable for seeds, and small donor sectors upstream might enhance the reestablishment of target vegetation along new sectors downstream.

The break-up of the Soviet Union in 1991 triggered cropland abandonment on a continental scale, which in turn led to carbon accumulation on abandoned land across Eurasia. Previous studies have estimated carbon accumulation rates across Russia based on large-scale modelling. Studies that assess carbon sequestration on abandoned land based on robust field sampling are rare. We investigated soil organic carbon (SOC) stocks using a randomized sampling design along a climatic gradient from forest steppe to Sub-Taiga in Western Siberia (Tyumen Province). In total, SOC contents were sampled on 470 plots across different soil and land-use types. The effect of land use on changes in SOC stock was evaluated, and carbon sequestration rates were calculated for different age stages of abandoned cropland. While land-use type had an effect on carbon accumulation in the topsoil (0-5 cm), no independent land-use effects were found for deeper SOC stocks. Topsoil carbon stocks of grasslands and forests were significantly higher than those of soils managed for crops and under abandoned cropland. SOC increased significantly with time since abandonment. The average carbon sequestration rate for soils of abandoned cropland was 0.66 Mg C ha-1 yr-1 (1-20 years old, 0-5 cm soil depth), which is at the lower end of published estimates for Russia and Siberia. There was a tendency towards SOC saturation on abandoned land as sequestration rates were much higher for recently abandoned (1-10 years old, 1.04 Mg C ha-1 yr-1 ) compared to earlier abandoned crop fields (11-20 years old, 0.26 Mg C ha-1 yr-1 ). Our study confirms the global significance of abandoned cropland in Russia for carbon sequestration. Our findings also suggest that robust regional surveys based on a large number of samples advance model-based continent-wide SOC prediction.

Restoring depleted soil organic carbon (SOC) stocks of arable land to remove carbon from the atmosphere and offset fossil fuel emissions is a promising strategy for the mitigation of climate change. In agroecosystems conservational tillage practices and the abandonment of formerly plowed fields (ex-arable land) are shown to have the highest potential to sequester SOC. Nevertheless reported sequestration rates vary and the effects of environmental site conditions remain poorly understood. Our results are based on a meta-analysis of 273 paired SOC estimates from 65 publications which included only mineral soils from the temperate zone. SOC stocks of ex-arable grasslands with an average of 14years since abandonment were 18% larger compared to the SOC of arable land. Likewise, SOC stocks of never-plowed grassland plots were 11% larger than the SOC stocks of abandoned fields. The average sequestration rate was 0.72t Cha(-1)yr(-1). Semi-arid and sub-humid climate as well as low initial SOC stocks positively affected proportional SOC gains suggesting that the recovery of carbon stocks is not limited by low primary production. Therefore, the northward shift of cultivation areas in the temperate zone will lead to the abandonment of soils with high SOC recovery potential. However, if native soils are opened up elsewhere to compensate for yield losses due to abandonment the surplus of SOC in ex-arable land can easily be overcompensated by cultivation losses.

Following the collapse of the Soviet Union in 1991 around 45 million hectares of arable land became abandoned across Russia. Our study focused on the recovery potential and conservation value of grassland vegetation on ex-arable land in the Tyumen region of the Western Siberian grain belt. We compared ex-arable grasslands of different successional stages with ancient grasslands as reference for the final stage of succession along a climatic gradient from the pre-taiga to the forest steppe zone. Plant community composition and species richness of ex-arable land clearly developed towards reference sites over time, but even after 24 years of abandonment, the grassland vegetation had not totally recovered. The γ-diversity of vascular plants was slightly higher on ex-arable land than in ancient grasslands but the mean α-diversity was still moderately lower. A significant proportion of the vegetation of ex-arable land still consisted of ruderal and mesic grassland species and the number and cover of meadow-steppe species was significantly lower than in ancient grasslands. Grazing and time since abandonment positively affected the reestablishment of target grassland species, whereas it was negatively affected by the cover of grasses. In contrast to ex-arable land, the conservation value of arable land is only modest. Therefore, future intensification of land use is most likely less harmful if directed to existing arable land. Re-cultivation of ex-arable land and grassland improvement operations such as seeding of competitive grass species are major threats for the biodiversity of secondary grasslands on ex-arable land in the forest steppe zone of Western Siberia.

Arten- und blutenreiche Saume und Feldraine sind typische Elemente alter Kulturlandschaften mit groser Bedeutung fur den Biotopverbund. Besonders in intensiv genutzten Agrarlandschaften sind sie vielerorts durch Eutrophierung und ungeeignete Pflege degradiert oder durch Uberfuhrung in andere Nutzungsformen vollig verschwunden. Noch vorhandene naturliche Saumstrukturen weisen heute in den meisten Fallen nur noch einen Bruchteil ihres ursprunglichen Artenspektrums auf. Die Wiederherstellung des lebensraumtypischen Artenspektrums ist daher oftmals nur durch Neuanlage oder Aufwertung grasdominierter oder ruderalisierter Randstrukturen moglich. Dabei werden in der Regel standortangepasste Saatmischungen gebietseigener Herkunft nach grundlicher Bodenbearbeitung ausgesat. Eine regelmasige extensive Pflege moglichst durch abschnittweise Mahd mit Abtransport des Mahguts ist sowohl bei neu angelegten als auch bei noch vorhandenen Saumen und Feldrainen von groser Bedeutung fur die Forderung der Artenvielfalt.

Salzmarschen entwickeln sich in regelmasig uberfluteten stromungsberuhigten Bereichen der Meereskusten. Ihre Vegetation ist an Uberflutungen, Nasse und hohe Salzgehalte des Bodens angepasst und zeigt in Abhangigkeit von der Hohe uber dem mittleren Hochwasser eine charakteristische Zonierung, die sich durch Beweidung verschieben kann. Wichtige Okosystemfunktionen der Salzmarschen sind neben ihrer Habitatfunktion fur zahlreiche spezialisierte Arten die hohe Produktivitat, die Fahigkeit zur Kohlenstoffsequestrierung und die Bedeutung fur die Deichsicherheit als naturliche Wellenbrecher. Viele Salzmarschen sind in der Vergangenheit durch Eindeichungen verlorengegangen oder durch kunstliche Entwasserungsmasnahmen degradiert. Renaturierungsprojekte streben daher an, durch Deichruckverlegungen oder Deichoffnung eine naturnahe Uberflutungsdynamik wiederherzustellen und die Entwicklung naturnaher Prielsysteme zu fordern. Hinsichtlich des Einflusses der Beweidung auf Vegetation und Fauna von Salzmarschen lassen sich keine allgemeingultigen Empfehlungen ableiten. Je nach Ausgangsbedingungen mussen lokal angepasste Schutz- und Renaturierungsziele definiert und – wenn Beweidung erwunscht ist – geeignete Weidetiere und Beweidungsintensitaten zur Umsetzung der Ziele ausgewahlt werden.

Durch Bebauung, Bodenversiegelung, Abfalle und Abgase sind urbane Okosysteme stark verandert. Stadtboden sind gestort und durch technogene Substrate sowie extreme Standortbedingungen gekennzeichnet und die Spontanvegetation urban-industrieller Okosysteme ist durch Ruderalfluren mit hohen Anteilen an Neophyten gepragt. Durch naturliche Sukzession entstehen auf alteren Brachflachen Gebusche und Vorwalder. Elemente „gruner Infrastruktur“ wie Garten, Grunanlagen, urbane Walder oder Brachflachen sichern in Stadten vielfaltige Okosystemdienstleistungen wie Kaltluftentstehung und Frischluftaustausch, Wasserretention, Feinstaubfilterung, die Naherholung sowie Produktion von Nahrungsmitteln. Haufig stehen sie jedoch in Flachenkonkurrenz zu Bebauungsvorhaben. Bei der Renaturierung degradierter Okosysteme werden in Stadten unterschiedliche Ansatze verfolgt, die vor allem der Klimaanpassung, der Verbesserung der Erholungsfunktion und dem Naturschutz dienen. Die Entwicklung von Pionierfluren und Magerrasen kann gefordert werden, wenn nahrstoffarme Substrate erhalten und Bodenstorungen zugelassen werden. Passive Renaturierung ermoglicht die Entwicklung urban-industrieller Wildnis bis hin zu neuartigen urbanen Waldern. Der Wechsel von gepflegten Offenlandbereichen und freien Sukzessionsflachen fordert die Artenvielfalt und wird von Erholungssuchenden als besonders attraktiv empfunden.

Schon in der Antike sicherten Menschen mit Wiederaufforstungen Holzressourcen, aber erst im 20. Jahrhundert hat sich die aktive Wiederherstellung degradierter Okosysteme zur Forderung ihrer charakteristischen Artenvielfalt und Okosystemfunktionen entwickelt. Seit Ende der 1980er-Jahre ist die Renaturierungsokologie als anwendungsorientierter Zweig der wissenschaftlichen Okologie etabliert. Zur passiven Renaturierung eines degradierten Okosystems kann es durch naturliche Sukzession kommen, wenn anthropogene Storungen, Umweltbelastungen und Ausbreitungshemmnisse reduziert werden. Die aktive Renaturierung unterstutzt die Wiederherstellung eines durch den Menschen mehr oder weniger stark degradierten bis vollig zerstorten Okosystems in Richtung eines definierten Referenzzustands. Haufig geht es dabei um Okosystemdienstleistungen, die auch fur den Menschen von Bedeutung sind. Rekultivierung beschrankt sich auf die Wiedernutzbarmachung von Okosystemen, z. B. fur Land- und Forstwirtschaft oder Freizeitnutzung. Die jeweiligen Ziele der Renaturierung hangen vom ausgewahlten Referenzokosystem ab und mussen gesellschaftlich ausgehandelt werden.

Extensive green roofs (EGRs) offer several beneficial ecosystem services for sustainable urban development. However, most standard green roofs have been designed with species-poor plant mixtures containing non-native species. Aiming to increase the nature conservation values of EGRs, we developed and tested a vascular plant seed mixture including regionally occurring native sandy dry grassland species in experimental miniature roofs in Northwestern Germany (temperate oceanic climate) over 4 years. We tested the mixture at two seed densities (1 and 2 g/m2). Additionally, we tested seeding at 1 g/m2 and introducing raked plant material collected from an ancient dry grassland. The total establishment rates of sown species reached 92–96% in the first year, but dropped to 40–60% in the last 2 years, with the highest values for the plots with raked material. Twenty-four additional species (11 vascular, 7 lichen, and 6 moss species, including 7 red-list species) typical of sandy dry grasslands were introduced through the raked material. Vascular plants reached 60–70% cover in the second year. Severe drought periods in the third and the fourth year led to a strong decline of vascular plant cover then. As this cover was higher in the plots with raked material, we assume facilitative effects through the well-developed cryptogam layer containing a mix of pleurocarpous and acrocarpous mosses and lichens. Spontaneously establishing acrocarpous mosses in sown plots did not seem to provide this same function. We conclude that EGRs designed with regionally occurring sandy dry grassland plant species and especially the application of raked plant material from ancient grassland is a fruitful approach to increase the value of green roofs for native phytodiversity.

GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). GrassPlot collects plot records (relevés) from grasslands and other open habitats of the Palaearctic biogeographic realm. It focuses on precisely delimited plots of eight standard grain sizes (0.0001; 0.001; ... 1,000 m²) and on nested-plot series with at least four different grain sizes. The usage of GrassPlot is regulated through Bylaws that intend to balance the interests of data contributors and data users. The current version (v. 1.00) contains data for approximately 170,000 plots of different sizes and 2,800 nested-plot series. The key components are richness data and metadata. However, most included datasets also encompass compositional data. About 14,000 plots have near-complete records of terricolous bryophytes and lichens in addition to vascular plants. At present, GrassPlot contains data from 36 countries throughout the Palaearctic, spread across elevational gradients and major grassland types. GrassPlot with its multi-scale and multi-taxon focus complements the larger international vegetation-plot databases, such as the European Vegetation Archive (EVA) and the global database “sPlot”. Its main aim is to facilitate studies on the scale- and taxon-dependency of biodiversity patterns and drivers along macroecological gradients. GrassPlot is a dynamic database and will expand through new data collection coordinated by the elected Governing Board. We invite researchers with suitable data to join GrassPlot. Researchers with project ideas addressable with GrassPlot data are welcome to submit proposals to the Governing Board. Abbreviations: EDGG = Eurasian Dry Grassland Group; EVA = European Vegetation Archive; GrassPlot = Database of Scale-Dependent Phytodiversity Patterns in Palaearctic Grasslands; SAR = species-area relationship.

Urban brownfields can provide habitats for endangered native plant species but may also support invasive non-native species. The aim of our study was to develop and test different measures for the ecological restoration of an urban brownfield. We aimed to enhance native plant species richness by seeding two native forb seed mixtures containing 25 (HD-mixture) and 13 species (LD-mixture), respectively, without affecting spontaneously colonizing plant species of nature conservation value. Additionally, we tested the effects of species introduction and mowing on the establishment of invasive non-native plant species, woody species development, and perennial grass dominance. With establishment rates of 84% (HD) and 92% (LD) in the first study year and about 60% for both seed mixtures in the fourth year, species introduction was successful and led to rapid re-vegetation of the formerly bare brownfield. Although seeding did not result in increased species richness using either seed mixture, the dominance of perennial grasses was significantly reduced by the establishment of forb species from the HD-mixture. Overall, we observed the spontaneous establishment of ten plant species of conservation value; seeding affected these species only temporarily, in the second year. Seeding (with either seed mixture) and mowing both resulted in reduced cover of woody species and a lower frequency of the invasive non-native Robinia pseudoacacia. Our study demonstrated the high nature conservation value of dry and nutrient-poor urban brownfields for spontaneously occurring threatened plant species. Further studies have to evaluate if the reduced cover of grasses and woody species through introduction of site-specific native forb species might increase these sites’ aesthetic value and broader acceptance of brownfields by urban residents.

Standard extensive green roofs (EGRs) with their shallow substrate layers represent extreme sites for plant growth and therefore are planted mostly with drought-resistant species, including non-native plant species. As standard EGR substrates often lack potentially mutualistic soil microorganisms, it has been stated that inoculation with arbuscular mycorrhizal fungi (AMF) might increase plant performance and drought resistance. Aiming to support native biodiversity on EGRs, we tested whether AMF inoculation into standard green roof substrate can enhance plant performance and drought resistance of regionally occurring native dry grassland species. The results of a pot experiment with 11 native plant species growing with and without AMF inoculation showed considerable differences in fitness-relevant plant traits. Over 88 days of moderate drought conditions, inoculated plants produced 2.5 times more above-ground biomass than control plants. In addition, the number of inflorescences on inoculated plants was significantly higher in 5 out of 7 flowering species. Under severe drought stress created by stopping the water supply, however, inoculated plants wilted on average 2.38 days earlier than control plants. Although the underlying mechanisms of the observed results remain unresolved, AMF inoculation might help to enhance an earlier and higher seed set, facilitating the establishment of a soil seed bank, which is necessary for a self-sustaining plant population in drought-governed habitats such as EGRs.

After foundation of the Wadden Sea National Park, grazing and artificial drainage was ceased or reduced on large areas of the salt marshes at the Schleswig-Holstein mainland coast (Northern Germany). The effect of grazing cessation versus intensive and moderate grazing on vegetation diversity was studied on small (plant species richness on plots between 0.01 and 100 m2) and large scale (vegetation type richness per hectare) over 18 to 20 years by analysing data from long-term monitoring programs. Plant species richness and vegetation type richness increased strongly over time in all management regimes, because grazing-sensitive species increased first in ungrazed marshes and later dispersed to and established in intensively grazed marshes. Dominance of the tall, late-successional grass Elymus athericus on 7% to 52% of all moderately and ungrazed (primarily high marsh) plots led to a decrease in species richness. After 18 to 20 years, species richness was highest in moderately and intensively grazed high marshes. Differences were significant only on small plots of up to 4 m2. On the large scale, vegetation type richness in the low marsh was higher without grazing, while no differences were found in the high marsh. Our results indicate that grazing effects differ between spatial scales and that different spatial scales have to be considered for monitoring and evaluation of vegetation diversity in salt marshes. To conserve vegetation diversity on all scales, a large-scale mosaic of different management regimes should be maintained.

1 Departamento de Botânica, Universidade Federal do Rio Grande do Sul – UFRGS, Porto Alegre, RS, Brazil 2 Restoration Ecology, Center of Life and Food Sciences Weihenstephan, Technische Universitat Munchen – TUM, Freising, Germany 3 Programa de Pos-graduacao em Botânica, Universidade Federal do Rio Grande do Sul – UFRGS, Porto Alegre, RS, Brazil 4 Faculty of Agricultural Sciences and Landscape Architecture, Hochschule Osnabruck – University of Applied Sciences, Osnabruck, Germany 5 Department of Nature Conservation and Landscape Planning, Anhalt University of Applied Sciences, Bernburg, Germany 6 Terrestrial Ecology, Center of Life and Food Sciences Weihenstephan, Technische Universitat Munchen – TUM, Freising, Germany 7 Departamento de Ecologia, Universidade Federal do Rio Grande do Sul – UFRGS, Porto Alegre, RS, Brazil 8 Departamento de Plantas Forrageiras e Agrometeorologia, Universidade Federal do Rio Grande do Sul – UFRGS, Porto Alegre, RS, Brazil 9 EMBRAPA Pecuaria Sul, Bage, RS, Brazil 10Programa de Pos-graduacao em Ecologia, Universidade Federal do Rio Grande do Sul – UFRGS, Porto Alegre, RS, Brazil 11Parque Nacional Aparados da Serra, ICMBio, Cambara do Sul, RS, Brazil

The biennial plant Gentianella bohemica is a subendemic of the Bohemian Massif, where it occurs in seminatural grasslands. It has become rare in recent decades as a result of profound changes in land use. Using amplified fragment length polymorphisms (AFLP) fingerprint data, we investigated the genetic structure within and among populations of G. bohemica in Bavaria, the Czech Republic, and the Austrian border region. The aim of our study was (1) to analyze the genetic structure among populations and to discuss these findings in the context of present and historical patterns of connectivity and isolation of populations, (2) to analyze genetic structure among consecutive generations (cohorts of two consecutive years), and (3) to investigate relationships between intrapopulational diversity and effective population size (Ne) as well as plant traits. (1) The German populations were strongly isolated from each other (pairwise FST= 0.29–0.60) and from all other populations (FST= 0.24–0.49). We found a pattern of near panmixis among the latter (FST= 0.15–0.35) with geographical distance explaining only 8% of the genetic variance. These results were congruent with a principal coordinate analysis (PCoA) and analysis using STRUCTURE to identify genetically coherent groups. These findings are in line with the strong physical barrier and historical constraints, resulting in separation of the German populations from the others. (2) We found pronounced genetic differences between consecutive cohorts of the German populations (pairwise FST= 0.23 and 0.31), which can be explained by local population history (land use, disturbance). (3) Genetic diversity within populations (Shannon index, HSh) was significantly correlated with Ne (RS= 0.733) and reflected a loss of diversity due to several demographic bottlenecks. Overall, we found that the genetic structure in G. bohemica is strongly influenced by historical periods of high connectivity and isolation as well as by marked demographic fluctuations in declining populations.

Dry grasslands in Europe are mostly of zoo-anthropogenic origin, but nevertheless they are among the most diverse plant communities of the world at small spatial scales, and they support a significant proportion of the biodiversity of the continent. Both agricultural intensification and abandonment of former dry grasslands caused dramatic losses in area and quality of this habitat type during recent decades. Here we report from the 7th European Dry Grassland Meeting, organised by the European Dry Grassland Group (EDGG) in Smolenice, Slovakia, in 2010. Under the motto ‘‘Succession, restoration and management of dry grasslands’’ one hundred researchers from throughout Europe discussed conservation issues of this threatened habitat type. We give a brief introduction to those nine articles that are included in this Special Feature. With contributions from many different countries and various dry grassland types, they address issues of conservation value, succession, management as well as regeneration and restoration. We conclude that the diversity of dry grasslands and their conservation problems require further research to develop adequate management techniques under changing frame conditions. However, also the frame conditions, such as the incentives for certain land use practices provided by the Common Agricultural Policy of the European Union need to be addressed if long-term success in conservation of dry grasslands is intended.

During recent decades, many studies have shown that the successful restoration of species-rich grasslands is often seed-limited because of depleted seed banks and limited seed dispersal in modern fragmented landscapes. In Europe, commercial seed mixtures, which are widely used for restoration measures, mostly consist of species and varieties of non-local provenance. The regional biodiversity of a given landscape, however, can be preserved only when seeds or plants of local provenance are used in restoration projects. Furthermore, the transfer of suitable target species of local provenance can strongly enhance restoration success. We review and evaluate the success of currently used near-natural methods for the introduction of target plant species (e.g. seeding of site-specific seed mixtures, transfer of fresh seed-containing hay, vacuum harvesting, transfer of turves or seed-containing soil) on restoration sites, ranging from dry and mesic meadows to floodplain grasslands and fens. Own data combined with literature findings show species establishment rates during the initial phase as well as the persistence of target species during long-term vegetation development on restoration sites. In conclusion, our review indicates that seed limitation can be overcome successfully by most of the reviewed measures for species introduction. The establishment of species-rich grasslands is most successful when seeds, seed-containing plant material or soil are spread on bare soil of ex-arable fields after tilling or topsoil removal, or on raw soils, e.g. in mined areas. In species-poor grasslands without soil disturbance and on older ex-arable fields with dense weed vegetation, final transfer rates were the lowest. For future restoration projects, suitable measures have to be chosen carefully from case to case as they differ considerably in costs and logistic effort. Long-term prospects for restored grassland are especially good when management can be incorporated in agricultural systems.

Jeschke M., Kiehl K., Pfadenhauer J. and Gigon A. 2008. Long-term effects of former management on the diversity of vascular plants, mosses and lichens in a calcareous grassland. Bot. Helv. 118: 95 – 109.

From 2003 to 2005, a sowing experiment was carried out over 26 months in newly created xerophytic grassland on calcareous gravel in order to show the effects of moss layer removal on vascular plant germination and establishment. Hand-collected seeds of Biscutella laevigata , Bromus erectus , Carex humilis and Linum perenne were sown on experimental plots with intact and removed moss layer. Germination percentages under controlled conditions in a germination chamber were about 80% for all species except for C. humilis (14%). No germination of C. humilis was detected throughout the field experiment. The moss layer significantly reduced germination and seedling survival of Biscutella , Bromus and Linum . On all plots, seed germination was highest in October 2003 and continued in spring and summer 2004 to a lesser extent. Seedling mortality was highest during dry periods in summer 2004 and 2005. In winter 2004/2005, mortality showed a peak on plots with removed moss layer, but not on plots with intact moss layer. This indicates a protective role of the moss layer against heavy frosts. The barrier function and shading caused by mosses were probably the most important factors with negative effect on germination and establishment of the studied vascular plants. Water deficiency and high temperatures seemed to be the main hazards for survival of young plants as the moss layer offered no protection against these factors.

The effects of different restoration measures and management variants on the vegetation development of newly created calcareous grasslands were studied in southern Germany from 1993 to 2002. In 1993, fresh seed-containing hay from a nature reserve with ancient calcareous grasslands was transferred onto ex-arable fields with and without topsoil removal. Nine years after start of the restoration, the standing crop was lower and the cover of bare soil was higher on topsoil-removal sites than on sites without soil removal. Topsoil removal had a positive effect on the proportion of target species (class Festuco-Brometea), because the number and cover of productive meadow species (class Molinio-Arrhenatheretea) were reduced. Persistence of hay-transfer species and the number of newly colonizing target species were highest on topsoil-removal sites. On plots with and without soil removal, species richness and the number of target species increased quickly after hay transfer and were always higher on hay-transfer plots than on plots that had not received hay in 1993. In 2002, differences induced by hay transfer were still much more pronounced than differences between management regimes. Management by mowing, however, led to higher species richness, a greater number of target species and a lower number of ruderals in comparison to no management on restoration fields without soil removal. A detrended correspondence analysis (DCA) indicated that vegetation composition of the hay-transfer plots of the restoration fields still differed from the vegetation of ancient grasslands in the nature reserve. Vegetation of an ex-arable field in the nature reserve (last ploughed in 1959) showed an intermediate successional stage. In general our results indicate that the transfer of autochthonous hay is an efficient method for the restoration of species-rich vegetation, which allows not only quick establishment but also long-term persistence of target species.

In 2003, the last existing population of Pulsatilla patens in Germany was studied in the nature reserve “Garchinger Heide”, a calcareous grassland north of Munich. The aim of our study was to evaluate the endangerment of the species in ancient and young grasslands of the nature reserve. Therefore, the size, structure and generative reproduction of the population in relation to vegetation characteristics were investigated. Total population size and mean density of individual plants in different zones of the nature reserve were determined by a GPS-supported counting and compared to a mapping of 1991. The population structure was analyzed by counting the number of individuals of different age–state classes on 4 m2 plots in ancient and young grasslands of the nature reserve. The cover of phanerogams, cryptogams, litter and bare soil was studied in order to characterize habitat quality. In 2003, about 9700 individuals of P. patens were counted which means that population size strongly decreased in comparison to 1991 (about 27 000). In the ancient grasslands, the number of individuals of all age–state classes of P. patens correlated negatively with the cover of phanerogams and litter. In contrast, phanerogam and cryptogam cover had a positive influence on the number of individuals of all age–state classes on a topsoil-removal site due to protection from desiccation. This site was the only one in the nature reserve, where population size increased between 1991 and 2003. The large population size indicates that short-term endangerment or extinction of the species in the nature reserve is not very likely. Nevertheless, the management of the nature reserve has to be optimized in order to prevent a further long-term decrease of the population size of P. patens.

Summary Seedling emergence and early establishment of six fen species differing in seed mass and growth form were investigated under experimental land use with changed vegetation structure and under real land use in a calcareous fen. Seeds of all six species were sown in plots with different experimental land-use treatments: summer and autumn mowing with or without litter removal, trampling and abandonment. Additionally, emergence and survival of experimentally sown seeds was investigated under real land use on adjacent sites managed by mowing, grazing, intense trampling or abandonment. On abandoned plots and on plots without litter removal of the land-use experiment, emergence rates of all species were negatively affected either by high litter and moss cover or by tall canopy. No differences were found between autumn and summer mowing. Gap creation by experimental trampling did not increase germination rate. Under real land use, establishment of seedlings of most species was positively affected by litter cover and tall canopy. Trampling, in contrast, had a severe negative effect on seedling survival. The investigated species differed in their germination ability which was tested in the germination chamber and in their response to land use. Succisa pratensis with the highest seed mass germinated well in the chamber and in the field more or less regardless of land use. The low germination rate of Parnassia palustris in the germination chamber indicated a limitation of viable seeds. In the field, however, seedling emergence was additionally limited by microsite availability. Seeds of Serratula tinctoria and Primula farinosa germinated well in the germination chamber, but seedling recruitment in the field was hampered in the presence of a high litter or moss cover. Seeds of Tofieldia calyculata and Pinguicula vulgaris were strongly dependent on the availability of suitable microsites in the field. They hardly germinated under natural conditions, in spite of a high number of germinable seeds in the germination chamber.

In 1993, experiments on the restoration of calcareousgrasslands on ex-arable fields were started in order to pro-vide new habitats for species of a small nature reservewith ancient grasslands north of Munich (Germany). Theeffects of diaspore transfer by the application of seed-containing hay on vegetation establishment were studiedon restoration fields with and without topsoil removal for5 years. The aim of the study was to assess plant diversityfor the evaluation of restoration success by different meth-ods including determination of species with viable seeds inthe hay by germination tests, phenological investigationson hay-transfer source sites at the time of harvest, andvegetation analyses on the restoration sites. Total seedcontent of the hay and the number and composition ofplant species with viable seeds were affected by the timeof harvesting and differed between a site which had beenused as arable field until 1959 and ancient grassland sites.Nevertheless, the number of established hay-transferspecies showed only few differences between restorationfields. The proportion of species transferred to restorationfields in relation to the number of species with viableseeds in the hay was between 69 and 89%. Five years afterthe hay transfer, the proportion of the established specieswas still between 58 and 76%. Up to now, topsoil removalhad no significant effect on the number of established hay-transfer species. After triple hay application the absolutenumber of transferred grassland species was higher thanon sites with single hay application, but restoration effi-ciency was lower because many of the species with viableseeds in the hay did not establish. In general, our resultsshowed that the transfer of autochthonous hay is a success-ful method to overcome dispersal limitation in restorationprojects.Key words: calcareous grassland, germination, hay trans-fer, restoration, species reintroduction, species richness,topsoil removal, vegetation.IntroductionHabitat loss and habitat fragmentation are the majorreasons for species extinction in European seminaturalgrasslands (Fischer & Sto¨cklin 1997; WallisDeVries et al.2002). For many endangered species, the maintenance ofsmall nature reserve areas and other remnant habitats isnot sufficient to ensure a viable population size (Ehrenfeld2000; Adam 2001). Therefore, concepts and methods forgrassland restoration have to be developed (Rose´nv Pfadenhauer 2001; Poschlod W Bekker et al. 1997) or due to itsdepletion caused by long-term agricultural use (Graham& Hutchings 1988). Because many grassland species areregionally rare and have poor dispersal abilities, the spon-taneous reestablishment of target species—especially onisolated restoration sites—is unlikely (Hutchings & Booth1996; Bakker & Berendse 1999; Pywell et al. 2002). Thismeans that species transfer is necessary to reestablishspecies of ancient grasslands, e.g., on ex-arable land. Theapplication of seed-containing autochthonous hay or ofharvested shoots with ripe seeds is a successful techniqueto transfer plant species onto restoration sites (Pywellet al. 1995; Patzelt et al. 2001; Ho¨lzel & Otte 2003). Incontrast to the application of commercial seed mixtures,the transfer of hay from regional target communities guar-antees local provenance of seeds. Furthermore, the hayprovides safe sites for emerging seedlings, thus protectingthem from radiation and water loss (Molder 1997).For the evaluation of restoration measures, the assess-ment of species richness only as a measure for biodiversityis not sufficient (Mortimer et al. 1998). Instead, it is neces-sary to assess the establishment of certain species orspecies groups, which have to be selected in respect to therestoration targets. The efficiency of hay transfer as resto-ration method can be evaluated when the number ofspecies transferred from the donor site is set in relation tototal species richness of the donor area (e.g., Patzelt et al.2001). This absolute transfer rate is easily assessed, but itis not suitable for comparing the efficiency of differentrestoration measures when total species richness and theproportion of species with viable seeds differ between

The transfer of seed-containing hay is a restoration measure for the introduction of plant species of local provenance. We investigated the effect of hay transfer on species richness and on long-term establishment of target plant and grasshopper species on former arable fields with and without topsoil removal in comparison to reference sites in a nature reserve. Plant species richness, the number of target plant species, and Red List plant species were significantly positively affected by hay transfer, both on the scale of whole restoration fields and on permanent plots of 4 m 2 . Eight years after the start of the restoration, only few of the transferred plant species had disappeared and some target species were newly found. Grasshoppers were affected not by hay transfer but by topsoil removal. The proportion of target grasshopper and plant species and Red List grasshopper species was higher on topsoil removal sites with low standing crop and high cover of bare soil than on sites without soil removal. On topsoil removal sites without hay, however, plant species richness was very low because of the slow natural dispersal of the target species. Vegetation and grasshopper communities still differed between restoration fields and the nature reserve. Nevertheless, our results indicate that the transfer of autochthonous seedcontaining hay is a successful method to establish speciesrich grasslands with a high proportion of target species.

The effects of different forms of land use on germination and establishment of the rare fen species Succisella inflexa were investigated in seed introduction experiments in a mown and an abandoned fen meadow in SE Germany. Treatments included abandonment, mowing in fall and mowing with creation of gaps in the moss and litter layer. Floating capacity of seeds was tested in order to estimate potential dispersal by water. On the mown meadow, gaps had a slightly positive effect on germination rates, while greatly increasing seedling survival until the next spring. At the abandoned site, litter inhibited germination, whereas mosses had a negative effect on germination and a positive effect on survival rates during the first year after germination. Both germination and seedling establishment were negatively affected by the presence of slug herbivores. On the abandoned site, no seedlings at all survived until the next spring. Even though seeds of Succisella inflexa were capable to float for several week...

The impact of cattle grazing on the vegetation of calcareous fens was compared to the effects of traditional autumn mowing in southern Germany. Vegetation composition was studied in adjacent pairs of fen meadows and pastures with similar environmental conditions and biomass production. Vegetation data were analysed with respect to species richness, species composition and response of species traits to disturbance, including morphology, defence mechanisms, clonal growth form and generative reproduction. Species richness was significantly reduced by grazing, but the percentage of typical fen species or Red Data Book species was not affected by land use type. Detrended Corrspondence Analysis indicated that species composition could best be explained in terms of a land use gradient. Species traits showed a clear trend in their response to land use type. Grazing favoured grasses and small forbs. Only a few species with defence mechanisms against foraging were more frequent or abundant on pastures. Man...

The effects of reduction and cessation of sheep grazing on salt-marsh vegetation were studied on a formerly intensively grazed salt marsh in northern Germany. Plant species cover was recorded in 45 permanent plots from 1992 to 2000. In 1995, physical and chemical soil parameters were analysed. Results of Redundancy Analysis (RDA) indicated that salinity and the depth of anoxic conditions below the surface were the most important soil factors related to the spatial vegetation pattern. Furthermore, plant species distribu- tion was influenced by present and past grazing intensity, by soil grain size and nitrogen content. Vegetation changes over 9 yr were analysed by non-linear regression. The cover of Aster tripolium, Atriplex portulacoides, and, to a lesser extent, Artemisia maritima and Elymus athericus increased due to reduced grazing pressure, whereas the cover of Salicornia europaea decreased. After a strong increase in the first years Aster decreased 2 to 6 yr after abandonment. In the mid salt-marsh zone Puccinellia maritima was replaced by Festuca rubra. The cover of Puccinellia, Festuca, Suaeda maritima, Glaux maritima and Salicornia fluctuated strongly, probably due to differences in weather conditions and inunda- tion frequency. Species richness per 4 m 2 generally increased while vegetation evenness decreased during the study period. Only in the high salt marsh abandoned for 9 yr did the number of species decrease slightly. Thus far, cessation of grazing did not lead to large-scale dominance of single plant species.

As increased nutrient availability due to drainage is considered a major cause of eutrophication in wetlands rewetting of drained wetlands is recommended as a restoration measure. The effect of soil drying and rewetting on the contribution of various nutrient release or transformation processes to changed nutrient availability for plants is however weakly understood. We measured effects of soil drying and re-wetting on N mineralization, and denitrification, as well as on release of dissolved organic nitrogen (DON), phosphorus, and potassium in incubated soil cores from a wet meadow in southern Sweden. Additionally, the impact of re-wetting with sulphate-enriched water was studied. Soil drying stimulated N mineralization (3 times higher) and reduced denitrification (5 times lower) compared to continuously wet soil. In the wet cores, denitrification increased to 20 mg N m(-2) d(-1), which was much higher than denitrification measured in the field. In the field, increased inorganic-N availability for plants due to drainage seemed primarily to be caused by increased N mineralization, and less by decreased denitrification. Soil drying also stimulated the release of DON and K, but P release was not affected. Re-wetting of dried soil cores strongly stimulated denitrification (up to 160 mg N m(-2) d(-1)), but N mineralization was not significantly decreased, neither were DON or K release. In contrast, the extractable P pool increased upon soil wetting. Re-wetting with sulphate-enriched water had no effect on any of the nutrient release or transformation rates. We conclude that caution is required in re-wetting of drained wetlands, because it may unintendently cause internal eutrophication through an increased P availability for plants.