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Responses to climate change have often been found to lag behind the rate of warming that has occurred. In addition to dispersal limitation potentially restricting spread at leading range margins, the persistence of species in new and unsuitable conditions is thought to be responsible for apparent time-lags.Soil seed banks can allow plant communities to temporarily buffer unsuitable environmental conditions, but their potential to slow responses to long-term climate change is largely unknown. As local forest cover can also buffer the effects of a warming climate, it is important to understand how seed banks might interact with land cover to mediate community responses to climate change.We first related species-level seed bank persistence and distribution-derived climatic niches for 840 plant species. We then used a database of plant community data from grasslands, forests and intermediate successional habitats from across Europe to investigate relationships between seed banks and their corresponding herb layers in 2763 plots in the context of climate and land cover.We found that species from warmer climates and with broader distributions are more likely to have a higher seed bank persistence, resulting in seed banks that are composed of species with warmer and broader climatic distributions than their corresponding herb layers. This was consistent across our climatic extent, with larger differences (seed banks from even warmer climates relative to vegetation) found in grasslands.Synthesis. Seed banks have been shown to buffer plant communities through periods of environmental variability, and in a period of climate change might be expected to contain species reflecting past, cooler conditions. Here, we show that persistent seed banks often contain species with relatively warm climatic niches and those with wide climatic ranges. Although these patterns may not be primarily driven by species' climatic adaptations, the prominence of such species in seed banks might still facilitate climate-driven community shifts. Additionally, seed banks may be related to ongoing trends regarding the spread of widespread generalist species into natural habitats, while cool-associated species may be at risk from both short- and long-term climatic variability and change. Responses to climate change have often been found to lag behind the rate of warming that has occurred. In addition to dispersal limitation potentially restricting spread at leading range margins, the persistence of species in new and unsuitable conditions is thought to be responsible for apparent time-lags. Soil seed banks can allow plant communities to temporarily buffer unsuitable environmental conditions, but their potential to slow responses to long-term climate change is largely unknown. As local forest cover can also buffer the effects of a warming climate, it is important to understand how seed banks might interact with land cover to mediate community responses to climate change. We first related species-level seed bank persistence and distribution-derived climatic niches for 840 plant species. We then used a database of plant community data from grasslands, forests and intermediate successional habitats from across Europe to investigate relationships between seed banks and their corresponding herb layers in 2763 plots in the context of climate and land cover. We found that species from warmer climates and with broader distributions are more likely to have a higher seed bank persistence, resulting in seed banks that are composed of species with warmer and broader climatic distributions than their corresponding herb layers. This was consistent across our climatic extent, with larger differences (seed banks from even warmer climates relative to vegetation) found in grasslands. Synthesis. Seed banks have been shown to buffer plant communities through periods of environmental variability, and in a period of climate change might be expected to contain species reflecting past, cooler conditions. Here, we show that persistent seed banks often contain species with relatively warm climatic niches and those with wide climatic ranges. Although these patterns may not be primarily driven by species' climatic adaptations, the prominence of such species in seed banks might still facilitate climate-driven community shifts. Additionally, seed banks may be related to ongoing trends regarding the spread of widespread generalist species into natural habitats, while cool-associated species may be at risk from both short- and long-term climatic variability and change.

Aim\ud \ud Climate and land use are key determinants of biodiversity, with past and ongoing changes posing serious threats to global ecosystems. Unlike most other organism groups, plant species can possess dormant life‐history stages such as soil seed banks, which may help plant communities to resist or at least postpone the detrimental impact of global changes. This study investigates the potential for soil seed banks to achieve this.\ud \ud \ud \ud Location\ud \ud Europe.\ud \ud \ud \ud Time period\ud \ud 1978–2014.\ud \ud \ud \ud Major taxa studied\ud \ud Flowering plants.\ud \ud \ud \ud Methods\ud \ud Using a space‐for‐time/warming approach, we study plant species richness and composition in the herb layer and the soil seed bank in 2,796 community plots from 54 datasets in managed grasslands, forests and intermediate, successional habitats across a climate gradient.\ud \ud \ud \ud Results\ud \ud Soil seed banks held more species than the herb layer, being compositionally similar across habitats. Species richness was lower in forests and successional habitats compared to grasslands, with annual temperature range more important than mean annual temperature for determining richness. Climate and land‐use effects were generally less pronounced when plant community richness included seed bank species richness, while there was no clear effect of land use and climate on compositional similarity between the seed bank and the herb layer.\ud \ud \ud \ud Main conclusions\ud \ud High seed bank diversity and compositional similarity between the herb layer and seed bank plant communities may provide a potentially important functional buffer against the impact of ongoing environmental changes on plant communities. This capacity could, however, be threatened by climate warming. Dormant life‐history stages can therefore be important sources of diversity in changing environments, potentially underpinning already observed time‐lags in plant community responses to global change. However, as soil seed banks themselves appear, albeit less, vulnerable to the same changes, their potential to buffer change can only be temporary, and major community shifts may still be expected.

Management of semi-natural grasslands is essential to retain the characteristic diversity of flora and fauna found in these habitats. To maintain, restore or recreate favourable conditions for grassland species, knowledge regarding how they occur in relation to grazing intensity and soil nutrient availability is crucial. We focused on grassland plant species, i.e., species selected to indicate high natural values in semi-natural grasslands. Environmental monitoring data collected at 366 grassland sites in southern Sweden between 2006 and 2010 were used to relate the occurrence of indicator species to factors describing geographic location, local site conditions related to nutrients and moisture, and management. Site productivity, soil moisture and cover of trees and shrubs were the main structuring factors, while other factors related to management had a lesser effect (grass sward height, amount of litter, type of grazer). Not surprisingly, these patterns were also reflected in species-wise analyses of the 25 most commonly occurring indicator species, with almost all species negatively related to site productivity and most also to soil moisture. Furthermore, many species were negatively affected by increasing sward height and litter. In contrast, species-wise responses varied among species in relation to increasing cover of trees and shrubs. In comparison to cattle grazing, sheep grazing was detrimental to six species and beneficial to none, while horse grazing was detrimental to no species and beneficial to four species. When evaluating species traits, taller plant species were favoured when site productivity, grass sward height and the amount of grass litter were high. There were no strong patterns related to the flowering time, leaf arrangement, or nutrient and light requirements of species. These results highlight the importance of nutrient-poor and dry sites, e.g., when selecting sites for conservation, and the importance of the type of management executed.

This study identifies and analyses multiple factors that impact peoples interactions with urban greenspace in Sweden. An unrestricted, self-selected online survey was used to collect the data. The survey questions were related to individual characteristics of respondents, including socio-demographic characteristics, self-reported nature connectedness, and self-reported constraints to greenspace usage; perceived characteristics of urban greenspace, including its availability, quality, and accessibility, and benefits and problems; and preferences of respondents regarding types of urban greenspace and activities. Additionally, several spatially explicit variables were included in the analysis. A total of 2806 respondents from 208 (of 290) municipalities completed the survey. Our findings indicate that greenspace users are highly heterogeneous and utilise diverse green spaces along the urban-peri-urban gradient for various benefits. The statistical analyses identified 61 explanatory variables that affect the frequency of interactions with urban greenspace. In addition, we identify key factors that shape critical differences between frequent and infrequent urban users, such as nature connectedness, perceptions of urban greenspace functions, and their perceived accessibility. Our results highlight the complex challenge facing urban planners and managers of green spaces, who have to consider and integrate a vast array of factors influencing the willingness of increasingly diverse urban populations to interact with greenspace. Funding Agencies|Swedish Research Council FORMAS [2019-01898]

We introduce the AusTraits database - a compilation of values of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 448 traits across 28,640 taxa from field campaigns, published literature, taxonomic monographs, and individual taxon descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological attributes (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised individual- and species-level measurements coupled to, where available, contextual information on site properties and experimental conditions. This article provides information on version 3.0.2 of AusTraits which contains data for 997,808 trait-by-taxon combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data, which also provides a template for other national or regional initiatives globally to fill persistent gaps in trait knowledge., Measurement(s)plant traitTechnology Type(s)digital curationSample Characteristic - OrganismViridiplantaeSample Characteristic - LocationAustralia Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.14545755

Arazi kullanimindaki degisiklikler nedeniyle Dogu Akdeniz Havzasi’nda yer alan mera niteligi de tasiyan ormanlar hizla yok olmaktadir. Geleneksel tarim ve hayvancilik faaliyetlerden keci yetistiriciligi ve yemlik dal yararlanmasi, bu sahalarda yer alan agaclarin yaslanarak uzun yillarca hayatta kalmasini saglayarak biyolojik cesitlilik icin son derece degerli habitatlar yaratmistir. Korunmasi gereken bu habitatlar icin etkili ve uygulanabilir yonetim planlarinin gelistirilmesi, habitat yapisi ve ona bagli turler arasindaki iliskileri tanimlamayi hedefleyen calismalari gerektirmektedir. Bu calismada, Turkiye'nin guneybatisinda yer alan yasli bir mese ormaninda transekt yontemi ile gerceklestirilen habitat envanterlerinden elde edilen veriler kullanilarak, habitat yapisi ile kus turu cesitliligi arasindaki iliskiler detayli bir olcekte ele alinmistir. Genellikle sahada tespit edilen kus turlerinin yogunlugunun; agacin govde buyuklugu, gogus yuzeyi veya sikligin artmasiyla dogru orantili oldugu tespit edilmistir. Yerde yuvalanan kus turlerinin cesitliligi uzerinde agaclarin gogus yuzeyi artisi ile nispeten pozitif bir iliskisinin oldugu tespit edilmis; cali ve agaccik yogunlugundaki artisin, alcak seviyelerde yuvalanan kus turleri uzerinde olumlu, ancak yuksek seviyelerde yuvalanan kus turleri acisindan olumsuz bir etkisinin oldugu belirlenmistir. Oyuk ve kovuklarda ikincil olarak yuvalanan kus turlerinin, kucuk govde oyuklarinin yogunlugu ile herhangi bir olumlu ya da olumsuz iliskisine rastlanmazken, gogus yuzeyi artisi ile olumlu bir iliskisinin oldugu tespit edilmistir. Bununla birlikte, oyuk ve kovuklarda birincil olarak yuvalanan kus turlerinin daha buyuk oyuklara sahip agaclari tercih ettigi gorulmustur. Ancak bu durum muhtemelen bu agaclarin diger olumlu ozelliklerinden de kaynaklanmis olabilir. Bu calismanin sonuclari, uzerinde az sayida calisma yapilmis ancak, tur cesitliligi bakimndan zengin olan ve isletilen Akdeniz ekosistemlerindeki kus topluluklarinin yapisi ve dagilimi hakkinda onemli bilgiler vermektedir.

When assessing changes in populations of species, it is essential that the methods used to collect data have some level of precision and preferably also good accuracy. One commonly used method to collect pollinators is colour pan traps, but this method has been suggested to be biased by the abundance of surrounding flowers. The present study evaluated the relationship between pan trap catches and the frequency of flowers on small (25 m2) and large (2–6 ha) spatial scales. If pan traps work well, one should assume a positive relationship, that is, more insects caught when they have more food. However, in contrast, we found that catches in pan traps were often negatively affected by flower frequency. Among the six taxa evaluated, the negative bias was largest in Vespoidea and Lepturinae, while there was no bias in solitary Apoidea (Cetoniidae, Syrphidae and social Apoidea were intermediate). Furthermore, red flowers seemed to contribute most to the negative bias. There was also a tendency that the negative bias differed within the flight season and that it was higher when considering the large spatial scale compared to the small one. To conclude, pan trap catches may suffer from a negative bias due to surrounding flower frequency and color. The occurrence and magnitude of the negative bias were context and taxon dependent, and therefore difficult to adjust for. Thus, pan traps seem less suited to evaluate differences between sites and the effect of restoration, when gradients in flower density are large. Instead, it seems better suited to monitor population changes within sites, and when gradients are small., Colour pan traps are often recommended for pollinator monitoring. We report that pan trap catches may suffer from a negative bias due to surrounding flower frequency and color. The occurrence and magnitude of the negative bias were context and taxon dependent, and therefore difficult to adjust for. Thus, pan traps seem less suited when gradients in flower density are large. Instead, it seems better suited to monitor population changes within sites, and when gradients are small.

Artificial light is an important and necessary part of urban environments, but light can have substantial direct and indirect effects on populations of various organisms. Urban areas are often situated close to water and thus organisms dependent on water could be especially vulnerable. Trichoptera is one of the most abundant insect orders in freshwater, but its attraction to light has not been analysed in detail. We contrasted catches in light traps and passive traps at three locations in Sweden. The results showed that artificial light can affect Trichoptera populations. Attraction to light varied between Trichoptera species and females were more attracted than males. Day-, evening- and especially night-active species were all attracted to light. Light catches of day- and evening-active Trichoptera could partly be a consequence of atypical flight activity, i.e. they are deceived to take flight when a lamp is lit during night. In all, artificial light can alter Trichoptera populations, sex ratios and species composition. This impact should be considered when erecting and managing light sources near waterways.

Loss and fragmentation of semi-natural grasslands has critically affected many butterfly species in Europe. Habitat area and isolation can have strong effects on the local biodiversity but species may also be strongly affected by the surrounding matrix. We explored how different land cover types in the landscape explained the occurrence of butterfly species in semi-natural grasslands. Using data from 476 semi-natural grasslands in Sweden, we analysed the effect of matrix composition on species richness and occurrence. Additionally, we analysed at which spatial scales butterflies responded to matrix types (forests, semi-natural grasslands, arable land and water). Forest cover showed the strongest positive effect on species richness, followed by semi-natural grasslands. Forest also had a positive effect on red-listed species at local scales. Responses to matrix composition were highly species-specific. The majority of the 30 most common species showed strong positive responses to the amount of forest cover within 200–500 m. There was a smaller group of species showing a positive response to arable land cover within 500–2000 m. Thirteen species showed positive responses to the amount of semi-natural grasslands, generally at larger scales (10–30 km). Our study showed that surrounding forest is beneficial for many grassland butterfly species and that forests might mitigate the negative effects of habitat loss caused by agricultural intensification. Also, semi-natural grasslands were an important factor for species richness at larger spatial scales, indicating that a landscape consisting mainly of supporting habitats (i.e. forests) are insufficient to sustain a rich butterfly fauna.

Mowing is an important management method for species-rich semi-natural grasslands in Europe. Since mowing is costly, it is important to find a balance between mowing frequency and conservation benefits. We compared vegetation data from eleven field trials situated in southern Sweden that involved two mowing regimes, annually and every third year, as well as a no-management control. After approximately 14 years, mowing every third year showed (i) a drop in species richness and Shannon and GiniSimpson diversity indices, (ii) an increase in woody species, and (iii) increases in tall-grown species. However, there were no apparent changes in (iv) species that were indicative of poor management, nor (v) those indicating good management. For one of the trials, data after 38 years were also evaluated. Compared with annual mowing, there were strong negative changes in the number of species in the untreated control, while the results were conflicting for mowing every third year. In conclusion, the expected loss of conservation values from reduced mowing intensity was 5060% of the loss after abandonment. The outcomes, however, varied among the eleven sites. (C) 2017 Gesellschaft fur Okologie. Published by Elsevier GmbH. All rights reserved. Funding Agencies|Swedish Board of Agriculture

During the last centuries, land use in Europe intensified, which has led to a drastic decrease in the cover of semi-natural grasslands. In Sweden, much of the lost grasslands was turned into forest. This study investigated if species typical of managed grasslands could be found in coniferous production forests more than 80 years after grassland management ceased. Species and trait composition for plants was investigated in two types of forest differing in land use history (meadow in the 1870s or continuous coniferous forest), and in reference grasslands. The average plant species richness as well as the richness of grassland indicator species were 30% higher in forests with a history as meadow compared to in forests with a history as forest, hence clear signs of historical grassland management in todays forests. Compared with forests with continuous coniferous history, vegetation in forests with a meadow history tended to be more similar to reference grassland regarding both plant species and especially plant trait composition. The study provides proof of remnant grassland populations in coniferous production as the source for the biodiversity of clearcuts, rather than seed dispersal or seed bank survival. The result highlights the importance of land use for biodiversity of clearcuts, and points to the potential value of forests with a history of meadow in grassland conservation and restoration. Funding Agencies|Swedish Forest Society

Pollinating insects are important and therefore, it is important to be able to assess and monitor changes in their abundance. Consequently, it is essential that the methods used to collect data have some level of precision and are accurate. In the present study, two commonly used methods: colour pan-traps and sweep netting along transects, were compared. A total of 1775 specimens of 120 species of four insect families were caught in twelve clear-cuts in southern Sweden. Overall, Lepturinae (Cerambycidae; 5 species) and Cetoniidae (Scarabaeidae; 2) were trapped in larger numbers by pan-traps and Syrphidae (62) and Apoidea, both social (10) and solitary (41), by sweep netting. The catches of none of the above groups of insects by the two methods were correlated. These results show that the composition of catches of the two methods are very different, which has implications when choosing a method for sampling or monitoring and comparing and analysing published data. Funding Agencies|Oscar and Lili Lamm Memorial Foundation

Old living oaks (Quercus robur) are known as a very species-rich habitat for saproxylic beetles, but it is less clear to what extent such veteran trees differ from an even rarer feature: downed trunks of large oaks. In this study, we set out to sample this habitat, using window traps, with two aims: (1) to describe the variation of assemblages among downed trunks of different type and (2) to compare beetles on downed oaks with data from veteran standing trees. The results showed that trunk volume and sun exposure better explained assemblages as well as species numbers on downed trunks than did decay stage. Furthermore, species classified as facultative saproxylic species showed weak or no differentiation among downed trunks. Species with different feeding habits showed no apparent differentiation among downed trunks. Furthermore, species composition on dead, downed oak trunks differed sharply from that of living, veteran oaks. Wood or bark feeders were more common on veterans than downed trunks, but there was no difference for those species feeding on fungi or those feeding on insects and their remains. In conclusion, for a successful conservation of the saproxylic beetle fauna it is important to keep downed oak trunks, and particularly large ones, in forest and pastures as they constitute a saproxylic habitat that differs from that of living trees. Funding agencies: Eklandskapsfonden (Linkoping municipality) Ostergotland County Administration Board

Synanthedon vespiformis L. (Lepidoptera: Sesiidae) is considered a rare insect in Sweden, discovered in 1860, with only a few observations recorded until a sex pheromone attractant became available recently. This study details a national survey conducted using pheromones as a sampling method for this species. Through pheromone trapping we captured 439 specimens in Southern Sweden at 77 sites, almost tripling the number of previously reported records for this species. The results suggest that S. vespiformis is truly a rare species with a genuinely scattered distribution, but can be locally abundant. Habitat analyses were conducted in order to test the relationship between habitat quality and the number of individuals caught. In Sweden, S. vespiformis is thought to be associated with oak hosts, but our attempts to predict its occurrence by the abundance of oaks yielded no significant relationships. We therefore suggest that sampling bias and limited knowledge on distribution may have led to the assumption that this species is primarily reliant on oaks in the northern part of its range, whereas it may in fact be polyphagous, similar to S. vespiformis found as an agricultural pest in Central and Southern Europe. We conclude that pheromones can massively enhance sampling potential for this and other rare lepidopteran species. Large-scale pheromone-based surveys provide a snapshot of true presences and absences across a considerable part of a species national distribution range, and thus for the first time provide a viable means of systematically assessing changes in distribution over time with high spatiotemporal resolution.

Both agricultural intensification and abandonment have led to the loss of European semi-natural grasslands. Nature conservation management measures like mowing are essential for preserving the biodiversity of remaining grasslands. However, there are no conclusive results from studies examining effects of different mowing frequencies across Europe. To fill this gap, we evaluated data from European studies comparing mowing frequencies to determine which are the most beneficial from a nature conservation viewpoint. We searched literature for short- and long-term studies comparing the effects of different mowing frequencies on outcome measures relevant for biodiversity conservation. We found 29 relevant studies where mowing once per year was compared to higher or lower mowing frequencies. The studies covered various grassland types and organisms. The effects were analysed using response ratios, where mowing once per year, i.e. the traditional mowing frequency in semi-natural grasslands, was compared to mowing every fifth, third or second year and mowing two, three or four times a year. Overall, we found similar effects of the different mowing frequencies on the biodiversity of flora and fauna. More frequent mowing generally had a more positive effect, but differences between frequencies were small. Effects were habitat-specific, differing between site and study conditions. For example, a higher mowing frequency was more beneficial in more productive grasslands. These results suggest that in most European semi-natural grasslands, mowing less frequently is a way of using the limited funds available for management more efficiently while still maintaining grassland conservation values, but e.g. site productivity must be considered when determining a suitable mowing frequency.

Corrigendum to "The biodiversity cost of reducing management intensity in species-rich grasslands: Mowing annually vs. every third year" [Basic Appl. Ecol. 22 (2017) 61-74]

Australian arid vegetation has evolved within highly variable environments characterised by low rainfall and sporadic fire events. Episodic high rainfall events are a significant factor in plant species recruitment, but their unpredictability makes them difficult to study. We report on the response of vascular plants to a major rainfall event and flood in an arid region of south-eastern Australia. Fire that occurred two months before the flood was incorporated into the study. Paired fenced and unfenced plots were established at control locations and also in areas that had been either flooded, burnt, or flooded and burnt. Objectives were to quantify the long-term effects of fire, flood and vertebrate herbivory, and their interactions, on vegetation composition, plant life forms and species diversity. We found that relative to controls (i) there was a significant effect of flooding on vegetation composition, (ii) changes in life form abundance were driven by flooding and grazing, (iii) there was a strong positive relationship between grazer exclusion and species diversity that was maintained over time and (iv) there was little effect of fire. Understanding the long-term effects of both natural disturbances and vertebrate herbivory will benefit plant conservation in the arid zone.

In a north European context, identifying invasive species is far from trivial because the vegetation has been influenced by human activities for thousands of years. New species have immigrated continuously since the end of the last glaciation, both spontaneously and through direct or indirect help by man. Still, newly immigrated species may be problematic in a nature conservation context and may harm biodiversity, and cause changes in ecosystem services. In this study, all 721 presently established vascular plant and bryophyte taxa known to have been introduced to, or to have immigrated to, Sweden since the year 1700 are assessed for their invasive potential. The assessment is based on six components considered relevant for their invasiveness: 1) ability to compete in natural vegetation, 2) ability to form dense populations, 3) realized dispersal ability, 4) gene flow to native relatives, 5) time since immigration and 6) distance to their native range. Although the relative importance of these components is context dependent, a compound general index of invasive concern is proposed and calculated for all taxa. The index of invasive concern is validated by comparing it to assessments by a Bayesian Belief Network in which the influences of the same six components are assigned by expert opinions. In addition, rough estimates of the present-day abundance of each taxon in Sweden are presented. The origin, biology and possible impact of the 150 taxa with the highest index values are discussed. Based on the index of invasive concern, Campylopus introflexus, Epilobium adenocaulon, E. ciliatum, Rosa rugosa, Lamiastrum galeobdolon subsp. argentatum, Orthodontium lineare, Solidago canadensis, Calystegia sepium subsp. spectabilis, Rubus armeniacus and Prunus serotina are identified as the ten most problematic alien vascular plant and bryophyte taxa in Sweden.

The Mediterranean basin exhibits a multitude of forest habitats affected by former and current exploitation and management. Recent afforestation programs have resulted in an increase in the proportion of coniferous trees, while oak stands, formerly utilized for coppicing and grazing, are abandoned or converted into coniferous plantations. The loss of oak stands might negatively affect birds dependent upon broadleaved forests. Studies confirming or rejecting that statement are scarce, particularly in the eastern part of the region. Using a study area in southwestern Turkey we applied a guild-based approach to investigate how pine and oak stands across a chronosequence differ in their capacity to support forest bird assemblages. Variables describing the vegetation were sampled to characterize the stands and relate bird assemblages to stand structure. Bird abundance and species richness was positively associated with age for both stand types. Richness and diversity was highest in oak stands, while there were no differences in bird abundance between the two forest types. Pine stands supported a different bird species composition compared to oak stands of the same age. Stand age and structure, rather than forest type, held the highest explanatory powers for bird assembly structure. Primary cavity-nesters and ground-nesters were more abundant in oak stands, possibly reflecting differences in stand structure and resource distribution. To support these birds with suitable habitats, oaks stands need conservation. Management practices in pine stands should strive for increasing the amount of old trees and retain vegetation in the understory to benefit breeding birds.

The sustainable management of unwanted vegetation in agricultural fields through integrated weed control strategies requires detailed knowledge about the maternal formation of primary seed dormancy, to support the prediction of seedling emergence dynamics. This knowledge is decisive for the timing of crop sowing and nonchemical weed control measures. Studies in controlled environments have already demonstrated that thermal conditions and, to some extent, water availability during seed set and maturation has an impact on the level of dormancy. However, it is still unclear if this applies also under field conditions, where environmental stressors and their timing are more variable. We address this question for Alopecurus myosuroides in south‐western Sweden. We quantified the effects of cumulated temperature and precipitation as well as soil water potential during the reproductive growth phase of A myosuroides on primary seed dormancy under field conditions. Empirical models differing in focal time intervals and, in case of soil water potential, focal soil depths were compared regarding their predictive power. The highest predictive power for the level of primary dormancy of A. myosuroides seeds was found for a two‐factorial linear model containing air temperature sum between 0 and 7 days before peak seed shedding as well as the number of days with soil water potential below field capacity between 7 and 35 days before peak seed shedding. For soil water potential, it was found that only the top 10 cm soil layer is of relevance, which is in line with the shallow root architecture of A. myosuroides. We conclude that for this species the level of dormancy depends on the magnitude and timing of temperature and water availability during the reproductive growth phase. Water availability appears to be more important during maternal environmental perception and temperature during zygotic environmental perception.

tCan data collected by practitioners during practical conservation work be used as decision support? Tofind out, we used unpublished data from attempts to enhance populations of the vascular plant Pulsatillavernalis in Sweden. About half of the 50 located cases had generated data useful for meta-analysis. Wecould show that burning had a positive effect while mechanical disturbance had negligible effects onnumber of plants in short-term follow-ups. Furthermore, we suggest that follow-up variables related toflowering are inferior for monitoring intervention success as flowering varies greatly between years. Inthe broader context, our example shows that simple records from practical conservation work can be arich source of information. It was also obvious that there is great potential for more useful evidence bymaking just small improvements in field protocols, documentation, and archiving. Finally, we suggestthat biologists and researchers need to develop an appreciation of "different levels of evidence", and thatin circumstances where we lack relevant experiments or observational studies, case studies might beuseful for improving interventions. Funding agencies: Biology Education Centre at Uppsala University

Aquatic plants can function as conduits for methane from sediment to the air. We studied the flux of methane from plots, in two Swedish lakes, dominated by two species (Phragmites australis, Carex rostrata). There were substantial seasonal differences (June to October), mainly tracking air temperature. There were large differences in flux during 24 h sampling, but with no consistent patterns between days. Emissions per m2 were similar for the two species. This suggests a system where CH4 production shapes emissions while species identity, and diurnal patterns, play a smaller role., Methane (CH4) emissions via emergent aquatic macrophytes can contribute substantially to the global CH4 balance. We addressed temporal variability in CH4 flux by using the static chamber approach to quantify fluxes from plots dominated by two species considered to differ in flux transport mechanisms (Phragmites australis, Carex rostrata). Temporal variability in daily mean emissions from early June to early October was substantial. The variable that best explained this variation was air temperature. Regular and consistent diel changes were absent and therefore less relevant to include when estimating or modelling CH4 emissions. Methane emissions per m2 from nearby plots were similar for Phragmites australis and Carex rostrata indicating that CH4 production in the system influenced emissions more than the species identity. This study indicates that previously observed diel patterns and species-effects on emissions require further evaluation to support improved local and regional CH4 flux assessments.

Plant species richness in central and northern European seminatural grasslands is often more closely linked to past than present habitat configuration, which is indicative of an extinction debt. In this study, we investigate whether signs of historical grassland management can be found in clear-cuts after at least 80 years as coniferous production forest by comparing floras between clear-cuts with a history as meadow and as forest in the 1870s in Sweden. Study sites were selected using old land-use maps and data on present-day clear-cuts. Species traits reflecting high capacities for dispersal and persistence were used to explain any possible links between the plants and the historical land use. Clear-cuts that were formerly meadow had, on average, 36% higher species richness and 35% higher richness of grassland indicator species, as well as a larger overall seed mass and lower anemochory, compared to clear-cuts with history as forest. We suggest that the plants in former meadows never disappeared after afforestation but survived as remnant populations. Many contemporary forests in Sweden were managed as grasslands in the 1800s. As conservation of remaining grassland fragments will not be enough to reduce the existing extinction debts of the flora, these young forests offer opportunities for grassland restoration at large scales. Our study supports the concept of remnant populations and highlights the importance of considering historical land use for understanding the distribution of grassland plant species in fragmented landscapes, as well as for policy-making and conservation.

The effect of applied vegetation science on society has the potential to increase by adopting an evidence-based approach. However, this would require a shift in focus towards effect size and results suitable for meta-analyses, a focus on practitioners as potential readers, more emphasis on practical problems rather than mechanism, and an acceptance of all well-executed experimental studies, even if confirmatory. Thus, the prevailing editorial policies need to be reconsidered, as well as the methods of analysing, reporting and evaluating research, for our research efforts to be of better use within society.

Biodiversity often suff ers from urbanization. In the present study, we focused on how the duration of urbanization aff ects therichness of 17 epiphytic lichen species and their cover on large oaks in urban environments in a city of 100 000 inhabitantsin southeast Sweden. We also surveyed trees in adjacent rural areas, selected to have similar distributions of tree trunkcircumference and surrounding oak density (within 300 m). Lichen richness and cover were lower on urban trees comparedto rural trees. Furthermore, richness and cover decreased with the length of time that urban trees had been surrounded byhouses. Most of the species that were analysed demonstrated a decline in occurrence with respect to the duration of housingdevelopment. Th e reduction in the probability of occurrence varied from 60% ( Calicium viride , Evernia prunastri ), 80%( Chrysothrix candelaris ) to 90% ( Ramalina spp.) during the considered 160-year period of urbanization. Th erefore, even ifvaluable trees survive over the course of development, their lichen biota is likely to become depleted over time.

One of the main natural disturbances that affects the structure of rain forests is treefalls, frequently resulting in gaps. Tree-fall gaps can bring drastic changes in environmental conditions compared with the undisturbed understory. We investigated the effect of tree-fall gaps on fruit-feeding butterfly (Nymphalidae) species assemblages in an undisturbed lowland rain forest in southeastern Peru. We used fruit-baited traps suspended 2 m above ground in 15 tree-fall gaps ranging in area from 100 to 1000 m2 and in adjacent undisturbed understory. Our data support the hypothesis that tree-fall gap and understory habitats are utilized by different butterfly species assemblages. There were morphological differences between gap and understory species, where the understory species had a larger wing area to thoracic volume. Vegetation structure and composition were important factors affecting the butterfly assemblages. Most of the butterfly species showed an avoidance of vines and a strong association with the presence of trees and shrubs in gaps. There were also differences among gap assemblages that increased with gap size. Some of the species that were associated with gaps have been considered as canopy species. Other gap species in the present study, however, are known to feed on fruits and/or use host plants mainly, or only, occurring in gaps, implicating that the gap assemblage is a mix of canopy species and those unique to gaps. This indicates that, in an undisturbed Amazon forest, tree-fall gaps may contribute to maintain species diversity by creating a mosaic of specific habitats and resources that favors different butterfly assemblages.

Within a successional context, the vegetation associated with the cedar glade ecosystem in middle Tennessee develops from bare limestone bedrock to subclimax redcedar, preclimax oak-hickory, and climax mixed hardwood forests. Studies on the composition and structure of forests associated with cedar glade–forming limestones (Lebanon, Ridley) are rare. We sampled the canopy and understory of six forest stands in middle Tennessee on these limestones. Observed number of canopy species was 14–24 across stands; estimated richness was greater by 1–3 species (bootstrap) or 3–6 species (first-order jackknife) than observed richness. With the exception of Ailanthus altissima in one stand, all other canopy species were native. Juniperus virginiana, Fraxinus americana, Carya ovata, and Quercus muehlenbergii were primary canopy components in 4 or 6 stands, and C. glabra, Q. shumardii, Ulmus alata, F. quadrangulata, Q. alba, and Q. velutina in 2–3 stands. When we included stands from a previously published s...

Biosphere Reserves aim at being role models for biodiversity conservation. This study focuses on the unsuccessful conservation of waders (Charadrii) on wet grasslands in the Kristianstad Vattenrike Biosphere Reserve (KVBR) in southern Sweden. Predation on nests and young has been proposed as one reason contributing to the decline of waders. We explored this hypothesis by comparing two landscapes, one with declining (KVBR) and one with stable (Östergötland) wader populations on managed wet grasslands in southern Sweden. Specifically, we tested three predictions linked to predation on wader nests and young, namely that (1) the relative abundance of avian predators and waders; (2) the avian predator abundance; and (3) the predation rate on artificial wader nests, should all be higher in declining versus stable populations. All predictions were clearly supported. Nevertheless, predation may not be the ultimate factor causing wader population declines. We discuss the cumulative effects of landscape change linked to increased food resources for predators, reduced wet grassland patch size and quality. Holistic analyses of multiple wet grassland landscapes as social-ecological systems as case studies, including processes such as predation and other factors affecting waders, is a promising avenue towards collaborative learning for wet grasslands as a functional green infrastructure. However, if governance and management approaches can be improved is questionable without considerable investment in both ecological and social systems.

Many saproxylic species are threatened in Europe because of habitat decline.Hollow trees represent an important habitat for saproxylic species. Artificial habitats mayneed to be created to maintain or increase the amount of habitat due to natural habitat decline.This study investigated the extent to which saproxylic beetles use artificial habitats in woodenboxes. The boxes were placed at various distances (0–1800 m) from known biodiversityhotspots with hollow oaks and studied over 10 years. Boxes were mainly filled with oak sawdust, oak leaves, hay and lucerne flour. In total, 2170 specimens of 91 saproxylic beetlespecies were sampled in 43 boxes. The abundance of species associated with tree hollows,wood rot and animal nests increased from the fourth to the final year, but species richnessdeclined for all groups. This study shows that wooden boxes can function as saproxylicspecies habitats. The artificial habitats developed into a more hollow-like environment duringthe decade long experiment with fewer but more abundant tree hollow specialists. Funding agencies: Stiftelsen Oscar och Lili Lamms minne; Eklandskapsfonden i Linkopings kommun

Plant species differ in their ability to transform available resources to biomass and to respond in a plastic way to environmental circumstances; we hypothesized that such differences among four weed taxa of Papaver would explain differences in their competitive response. We first compared two populations each of Papaver rhoeas L., P. dubium L. ssp. dubium, P. dubium L. ssp. lecoqii (Lamotte) Syme and P. argemone L., grown in a greenhouse for 6 weeks in a nutrient gradient combined with two light treatments to elucidate possible differences in responses. As there were clear differences, a second experiment evaluated whether these differences also meant differences in competitive response, during early growth, when tested against two crops (wheat, rape). The assumption that competitive response was linked to the ability to transform nutrient and light to biomass was not supported: even though differences in extent of plasticity existed, the effect of competition was similar for the taxa. Thus, higher plasticity and ability to transform available recourses to biomass did not lead to stronger competitiveness for Papaver during early growth.

Species-rich semi-natural grasslands in Europe are a main target for conservation efforts, and alternative methods to the traditional management of mowing or grazing would be welcome due to the dif ...

Oaks (Quercus robur) can reach a considerable age, which makes them an important substrate for many epiphytic lichens, including several red-listed species. We studied the importance of tree size and other environmental factors for the occurrence of six epiphytic lichens at two sites, in southeastern Sweden, differing in quality as judged by tree size distribution and number of old trees. The effects of tree circumference, light availability, trunk inclination and site were analysed. Results showed that different lichen species responded differently to these factors, but, overall, tree size was most important for lichen occurrence. Five species showed a positive relation to tree size, but the 50% probability of occurrence was reached at different tree sizes among these species and there were also site differences. This study shows that the maintenance of old trees is crucial for several lichen species, which highlights the importance of long-term management plans.

Old hollow trees have declined in Europe and many saproxylic (i.e. wood-dwelling) invertebrates living on them are threatened. The aim of this study was to investigate to what extent artificial habitats can be exploited by saproxylic beetles. To mimic the conditions in tree hollows, we constructed wooden boxes filled with different combinations of substrates like oak saw dust, oak leaves, dead hen (Gallus domesticus), chicken dung, lucerne flour or potatoes and placed them on tree trunks. To investigate the importance of distance from dispersal sources, we placed boxes at different distances (0 to 1800 m) from three species-rich sites with high densities of hollow oaks. Over three years, 3423 specimens of 105 saproxylic beetle species were caught in 47 boxes. Among beetles found in hollow oaks that were either tree-hollow species, nest species, or wood rot species, 70 % were also found in the boxes. A dead hen added to the artificial wood mould gave a higher number of beetle specimens. The number of species associated with tree hollows in oak decreased with distance from sites with hollow oaks. In conclusion, the prospects for using artificial environments for boosting substrate availability, or to fill spatial and temporal gaps therein, for saproxylic beetles are good. The original publication is available at www.springerlink.com:Nicklas Jansson, Thomas Ranius, Anna Larsson and Per Milberg, Boxes mimicking tree hollows can help conservation of saproxylic beetles, 2009, Biodiversity and Conservation.http://dx.doi.org/10.1007/s10531-009-9687-2Copyright: Springer Science Business Mediahttp://www.springerlink.com/