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Background: Predicting fire behaviour is an ongoing challenge in temperate peatlands and heathlands, where live fuels can form the dominant fuel load for wildfire spread, and where spatial heterogeneity in fuel moisture is important but not typically represented in fuel models. Aims: We examine the impact of fuel moisture variation on simulated fire behaviour across a temperate peatland/heathland landscape. Methods: We collected field measurements of fuel moisture content in Calluna vulgaris shrub from 36 sites across the North Yorkshire Moors, United Kingdom. We used these to define fuel moisture inputs within existing shrubland fuel models to simulate fire behaviour in BehavePlus. Key results: Simulated rates of spread varied with fuel moisture content; average mean variance of 23–80% from the landscape average rate of spread. The driest sites had simulated rates of spread up to 135% above the landscape average and the wettest sites up to 86% below average. Fuel model selection dramatically impacted simulated rates of spread by a factor of five. Conclusions: We need to constrain the role of live fuel moisture within temperate fuel models to develop accurate fire behaviour predictions. Implications: Capturing cross-landscape heterogeneity in fire behaviour is important for safe and effective land and wildfire management decision-making. Predicted fire behaviour varies significantly when cross-landscape fuel moisture differences are included in simulations. In temperate fuels, where live fuel moisture is not well represented in models, this may create dangerous situations where fire behaviour is underpredicted during the typical spring fire season, which has implications for fire management decision-making. [ABSTRACT FROM AUTHOR]

This study introduces a sustainable and environmentally friendly method for synthesizing selenium nanoparticles (SeNPs) by using Calluna vulgaris as a reducing agent. The process involves the addition of Na2SeO3 to a C. vulgaris aqueous solution, followed by reduction with ascorbic acid. UV-Vis spectroscopy confirmed SeNP formation, with a distinct absorption peak at 289 nm. Morphological analysis via Scanning Electron Microscopy (SEM) revealed spherical nanoparticles below 100 nm, as corroborated by Transmission Electron Microscopy (TEM) images displaying sizes ranging from 42.91 to 66.93 nm. Energy Dispersive Spectroscopy (EDS) confirmed the presence of selenium. Antibacterial assessments demonstrated the efficacy of C.vulgaris Selenium Nanoparticles (Cv-SeNPs) against gram-positive (Enterococcus faecalis, Staphylococcus aureus) and gram-negative bacteria (Escherichia coli). Cv-SeNPs exhibited notable antibacterial activity, particularly against E. Faecalis. In terms of antioxidant activities, Cv-SeNPs exhibited significant scavenging potential against DPPH and ABTS radicals, with low IC50 values of 24.72 and 16.87 µg/mL, respectively. The scavenging activities increased with concentration, reaching 86.6% for DPPH and 99.7% for ABTS at specific concentrations. The inclusion of ascorbic acid as a capping agent further augmented the free radical scavenging capabilities, indicating a synergistic relationship between selenium nanoparticles and capping agents. This research underscores the dual functionality of Cv-SeNPs as effective antibacterial agents and potent antioxidants. The green synthesis methodology utilizing C. vulgaris offers a sustainable approach for producing selenium nanoparticles with desirable characteristics, suggesting potential applications in medicine and industry. Further research on biomedical and industrial uses of Cv-SeNPs is needed. [ABSTRACT FROM AUTHOR]

Copyright of Fire Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Heathlands are unique cultural landscapes that once existed across vast stretches of northern Europe. Their deep-time persistence has formed an intrinsic part of economic and cultural practices. Such a complex interaction requires interdisciplinary approaches, including archaeology, across multiple regions to fully grasp all its aspects. The authors of this article review how research has been conducted in prehistoric heathlands across six nations in north-western Europe and outline the heaths' general characteristics. They discuss the major issues in that research, namely recurring narratives derived from history, an overall absence of consideration of the cultural aspects of heathlands, and a paucity of cross-regional initiatives. They suggest a series of theoretical and methodological approaches to improve this situation across expanded geographical and temporal scales. [ABSTRACT FROM AUTHOR]

Calluna vulgaris L. (heather) is a traditional medicinal plant with anti-inflammatory and calming activities that are determined by the notable amounts of phytochemicals. The evaluation of different populations of plants that accumulate great amounts of bioactive compounds are requisite for the quality determination of plant materials and medicinal and nutritional products. The assessment of natural resources from a phytogeographic point of view is relevant. Phytochemical analysis of heather samples was carried out using spectrophotometric methods and HPLC-PDA techniques, while antioxidant activity was determined using ABTS and FRAP assays. A significant diversification of phenolic and triterpenic compounds and antioxidant activity was determined in the heather samples collected in distinct habitats. Natural habitats, due to their characteristic chemical heterogeneity, lead to the diversity of indicators characterizing the quality of plant raw materials. Chlorogenic acid and hyperoside were found to be predominant among the phenolic compounds, while ursolic, oleanolic acids, and uvaol prevailed among the triterpenic compounds. Thus, these compounds can be suggested as phytochemical markers, characteristic of the heather raw material from central Europe. [ABSTRACT FROM AUTHOR]

Calluna vulgaris, belonging to the Ericaceae family, is an invasive plant that has widely spread from Europe all across Asia, North America, Australia and New Zealand. Being able to survive in rigid soil and environmental conditions, it is nowadays considered to be of high nature-conservation value. Known for its nutritional and medicinal properties, C. vulgaris stands out for its varied physiochemical composition, spotlighting a wide range of biological activity. Among the most important bioactive compounds identified in C. vulgaris, the phenolic components found in different parts of this herbaceous plant are the main source of its diverse pro-health properties (antioxidant, anti-inflammatory, antimicrobial, chemoprotective, etc.). Nonetheless, this plant exhibits an excellent nectariferous potential for social insects such as honeybees; therefore, comparing the bioactive compounds observed in the plant and in the final product of the beehive, namely honey, will help us understand and find new insights into the health benefits provided by the consumption of C. vulgaris-related products. Thus, the main interest of this work is to review the nutritional profile, chemical composition and biological activities of the C. vulgaris plant and its related honey in order to encourage the future exploration and use of this health-promoting plant in novel foods, pharmacological products and apitherapy. [ABSTRACT FROM AUTHOR]

Prescribed burning of vegetation is a land management approach that can be used to prevent or reduce the risk of wildfires yet burns can escape and be an ignition source for wildfires. In Scotland, muirburn is a form of prescribed burning used to encourage new growth of heather for grouse and livestock. Future regulation aims to mitigate potential negative impacts of muirburn on biodiversity, peat carbon stocks and wildfire risk. In this study, we assessed the spatial co-occurrence of muirburn and wildfires across Scotland. Evidence of muirburn was quantified using high-resolution aerial imagery from 2018 and wildfire occurrence was a composite of satellite and aerial detection covering 2015 to 2020. Fires were mapped on to dominant vegetation habitat types (acid grasslands, heather grasslands, heather heathlands, and peatbogs) and peat soil. Overall, 96 % of the total wildfire area occurred outside moorlands managed by muirburn, with wildfires covering 1.1 % of total moorland area. Heather grasslands, peatbogs and habitats on peat soils had a greater proportional area of wildfires than other moorland habitats and habitats on non-peat soils. In contrast, heather heathlands with non-peat soils had a greater proportional area of muirburn. We suggest the limited co-occurrence of muirburn and wildfires, may be due to fuel load reduction following muirburns, but may arise due to wildfire prevention strategies on estates and/or lower occurrence of recreational caused wildfires. In addition to muirburn regulation, our findings emphasise the need for policy, management, awareness and education outside of muirburn areas to reduce the risk of wildfires. • Mapped muirburn (prescribed burning) and wildfire area across Scottish moorlands • Overall, 96 % wildfire area occurs outside of moorland managed by muirburn • Between 2015 and 2020 wildfires covered 1.1 % of the moorland land area • Moorland vegetation and soil types differed in proneness to muirburn and wildfire [ABSTRACT FROM AUTHOR]

Heather, Calluna vulgaris, is a key species of European dry heath and central determinant of its conservation status. The established Calluna life cycle concept describes four phases—pioneer, building, mature, and degeneration—distinguishable by growth and vitality characteristics of undisturbed plants grown from seeds. However, little is known about the life cycle and ageing of plants subjected to severe disturbance, although measures to this effect (burning, mowing) are common in heathland management. We studied the vitality of over 400 heather plants by examining multiple morphological (plant height, long shoot and inflorescence lengths, flowering activity), anatomical (growth rings) and environmental (management, nitrogen deposition, climate) attributes. We found Calluna vitality to be mainly determined by the aboveground stem age, and that severe disturbances promote vigorous vegetative regeneration. Ageing-related shifts in the habit and vitality of plants resprouting from stem-base buds is similar to that of seed-based plants, but the former revealed higher vitality when young, at the cost of a shorter life span. In contrast, plants originating from decumbent stems resemble building-stage plants but apparently lack the capacity to re-enter a cycle including stages other than degeneration-type. As a consequence, we supplemented the established heather life cycle concept with a post-disturbance regeneration cycle of plants derived from resprouting. We conclude that management of dry lowland heathlands should include rotational small-scale severe disturbance to support both seed germination and seedling establishment as well as vegetative regeneration chiefly of young heather plants capable of resprouting from buds near rootstock. [ABSTRACT FROM AUTHOR]

The Calluna vulgaris honey produced in Portugal, concerning its phenolic compounds and abscisic acids profiles, as well as its antioxidant activity and the protective effect against oxidative damage in human erythrocytes were herein performed for the first time. The phenolic and abscisic acid profiles were tentatively identified by LC-MS/MS (17 compounds). The total content of phenolics and abscisic acids was 15,446.4 μg/g of honey extract, with catechin derivatives and abscisic acids being major constituents. The highest scavenging capacity was found against reactive nitrogen species. Additionally, the honey extract prevented ROO'-induced oxidative damage in erythrocytes collected from human blood, by inhibiting hemolysis, lipid peroxidation and hemoglobin oxidation. In conclusion, C. vulgaris honey contains high content of catechin derivatives and abscisic acids that may be responsible for its biological activity, characterized by a strong antioxidant capacity, which adds up to the nutritional value of this delicacy. [ABSTRACT FROM AUTHOR]

Winter temperatures are projected to increase in Central Europe. Subsequently, snow cover will decrease, leading to increased soil temperature variability, with potentially different consequences for soil frost depending on e.g. altitude. Here, we experimentally evaluated the effects of increased winter soil temperature variability on the root associated mycobiome of two plant species (Calluna vulgaris and Holcus lanatus) at two sites in Germany; a colder and wetter upland site with high snow accumulation and a warmer and drier lowland site, with low snow accumulation. Mesocosm monocultures were set-up in spring 2010 at both sites (with soil and plants originating from the lowland site). In the following winter, an experimental warming pulse treatment was initiated by overhead infrared heaters and warming wires at the soil surface for half of the mesocosms at both sites. At the lowland site, the warming treatment resulted in a reduced number of days with soil frost as well as increased the average daily temperature amplitude. Contrary, the treatment caused no changes in these parameters at the upland site, which was in general a much more frost affected site. Soil and plant roots were sampled before and after the following growing season (spring and autumn 2011). High-throughput sequencing was used for profiling of the root-associated fungal (ITS marker) community (mycobiome). Site was found to have a profound effect on the composition of the mycobiome, which at the upland site was dominated by fast growing saprotrophs (Mortierellomycota), and at the lowland site by plant species-specific symbionts (e.g. Rhizoscyphus ericae and Microdochium bolleyi for C. vulgaris and H. lanatus respectively). The transplantation to the colder upland site and the temperature treatment at the warmer lowland site had comparable consequences for the mycobiome, implying that winter climate change resulting in higher temperature variability has large consequences for mycobiome structures regardless of absolute temperature of a given site. [ABSTRACT FROM AUTHOR]

Calluna vulgaris L. (heather) is a traditional medicinal plant with anti-inflammatory and calming activities that are determined by the notable amounts of phytochemicals. The evaluation of different populations of plants that accumulate great amounts of bioactive compounds are requisite for the quality determination of plant materials and medicinal and nutritional products. The assessment of natural resources from a phytogeographic point of view is relevant. Phytochemical analysis of heather samples was carried out using spectrophotometric methods and HPLC-PDA techniques, while antioxidant activity was determined using ABTS and FRAP assays. A significant diversification of phenolic and triterpenic compounds and antioxidant activity was determined in the heather samples collected in distinct habitats. Natural habitats, due to their characteristic chemical heterogeneity, lead to the diversity of indicators characterizing the quality of plant raw materials. Chlorogenic acid and hyperoside were found to be predominant among the phenolic compounds, while ursolic, oleanolic acids, and uvaol prevailed among the triterpenic compounds. Thus, these compounds can be suggested as phytochemical markers, characteristic of the heather raw material from central Europe.

Copyright of Botanica Serbica is the property of University of Belgrade, Institute of Botany & Botanical Garden Jevremovac and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Questions: To improve our knowledge on how environmental conditions determine the development of high‐value Calluna vulgaris heathland habitats, we studied the floristic and structural characteristics of heathland plant communities across North Germany and how they are influenced by edaphic, climatic and management factors. We ask how heathland development is related to these factors and what are the implications for conservation management and restoration. Location: North German Plain. Methods: We collected 350 relevés in 18 dry Calluna heathland areas. Plant communities were classified using Isopam, and Redundancy Analysis (RDA) determined effects of environmental conditions. Potential pathways of development and the nature conservation status of the communities were identified on a multifactorial basis. Results: We found nine floristically and structurally distinct heathland plant communities. Heathland vegetation showed distinct patterns along Calluna age development stages and environmental conditions. Soil conditions and related effects of long‐term site history and recent management turned out to be the predominant factors influencing species composition and diversity, resulting in three potential heathland succession pathways. Mosaic‐like communities with particularly high taxonomic diversity and conservation value occurred on early‐successional inland dunes or as regeneration stage growing on nutrient‐poor sandy soils without humus accumulation. Conclusions: The study reveals fundamental differences between historically farmed heathland in the oceanic Northwest and former military training areas mainly in northeastern Germany with consequences for restoration ecology. Present nature conservation criteria turned out to be insufficient in predicting habitat quality, as lichens are frequently disregarded. Our findings highlight the need for intense soil disturbance to maintain early‐stage soil conditions and a diverse Calluna growth‐phase composition, as these factors essentially determine species richness in lowland heaths. [ABSTRACT FROM AUTHOR]

Background and Aims Plant secondary metabolites play critical roles in plant stress tolerance and adaptation, and are known to be influenced by the environment and climate changes, yet the impacts and interactions of multiple climate change components are poorly understood, particularly under natural conditions. Methods Accumulation of phenolics and emissions of volatile organic compounds (VOCs) were assessed on heather, Calluna vulgaris , an abundant evergreen dwarf shrub in European heathlands, after 6 years of exposure to elevated CO2, summer drought and nighttime warming. Key Results Drought alone had the strongest effects on phenolic concentrations and compositions, with moderate effects of elevated CO2 and temperature. Elevated CO2 exerted the greatest impact on VOC emissions, mainly by increasing monoterpene emissions. The response magnitudes varied among plant tissue types and chemical constituents, and across time. With respect to interactive effects of the studied climate change components, the interaction between drought and elevated CO2 was most apparent. Drought mainly reduced phenolic accumulation and VOC emissions, while elevated CO2 mitigated such effects. Conclusions In natural ecosystems, co-occurring climate factors can exert complex impacts on plant secondary metabolite profiles, which may in turn alter ecosystem processes. [ABSTRACT FROM AUTHOR]

Prunus serotina is one of the worst invasive alien plants throughout Europe, able to rapidly replace autochthonous vegetation and form monospecific stands both in open lands and forested areas. Invasion by shrubs and trees due to abandonment of traditional management practices, is one of the major threats to the conservation of "European dry heaths", a priority habitat included in the Council Directive 92/43/EEC. The aim of this study was to assess the effects of P. serotina invasion on heathland vegetation in terms of species composition and cover, with special regards to the dominant Calluna vulgaris and Molinia arundinacea, in an area of North-Western Italy subjected to massive invasion by this alien species. We collected data on the plant cover along an invasion gradient in 10 linear transects running from P. serotina invaded stands towards non invaded ones. P. serotina differently affected the heathland vegetation. In particular, the cover of C. vulgaris and other typical heathland species such as Cytisus scoparius sharply decreased at P. serotina cover increasing. On the contrary, positive or no effect of P. serotina cover was found on M. arundinacea. Our results showed that shaded conditions created by the alien tree disfavored light demanding C. vulgaris and C. scoparius, enabling fast grower M. arundinacea to outcompete and replace them. This study emphasizes the urgency to develop management strategies to effectively control P. serotina spread in the area and to restore typical heathland species. [ABSTRACT FROM AUTHOR]

Recent developments in high‐resolution ecosystem mapping using unmanned aerial vehicles (UAV) open up promising perspectives for the monitoring of fine‐scale vegetation patterns and ecological functioning. In this study, we examine the potential of UAV imagery to track the structural composition and related phenological traits of the dwarf shrub Calluna vulgaris on a former military training area. On a European Natura 2000 heathland site, habitat management is shown to be evaluated on the basis of flowering dynamics and reproductive recovery as a proxy of functional changes that are generated after fire destruction. In particular, we utilize true color camera information and digital surface models to determine the spatiotemporal evolution of Calluna life‐cycle phases and flowering phenology 2 years after controlled burning. A stepwise methodological framework is presented that extracts Calluna pixels, spatially separates juvenile and mature life‐cycle phases, differentiates between generative and vegetative shoot extension and finally quantifies proportions of flowers, fruits and vegetative growth in two consecutive peak flowering periods. We show that Calluna life‐cycle phases can be spatially differentiated in pioneer, building and mature phases in UAV imagery. In the juvenile phase, regeneration from germination is low (<10%) and sprouting from the stem base dominates recovery patterns after fire management. The study further reveals that the distribution of flowering and fruiting during peak flowering time is spatially heterogeneous with high variations between years. In the fire unaffected mature phase, proportions of flowers and fruits are reduced indicating a decrease in reproductive capacity of unmanaged Calluna stands. A phenological phase shift is detected from flowering to fruiting that is related to an increase of Calluna growth height. The study shows that the functional patterns of growth and reproduction can be mapped for heathland ecosystems using simple true color drone cameras. [ABSTRACT FROM AUTHOR]

Gastrointestinal nematode (GIN) infections impact small ruminant health, welfare, and production across farming systems. Rising anthelmintic resistance and regulation of synthetic drug use in organic farming is driving research and development of sustainable alternatives for GIN control. One alternative is the feeding of plants that contain secondary metabolites (PSMs) e.g., proanthocyanidins (PA, syn. condensed tannins) that have shown anthelmintic potential. However, PSMs can potentially impair performance, arising from reduced palatability and thus intake, digestibility or even toxicity effects. In this study, we tested the trade-off between the antiparasitic and anti-nutritional effects of heather consumption by lambs. The impact of additional feeding of a nematophagous fungus (Duddingtonia flagrans) on larval development was also explored. Lambs infected with Teladorsagia circumcincta or uninfected controls, were offered ad libitum heather, or a control chopped hay for 22 days during the infection patent period. Eight days into the patent period, parasitised lambs were supplemented (or remained unsupplemented) with D. flagrans for a 5-day period. Performance and infection metrics were recorded, and polyphenol levels in the heather and control hay were measured to investigate their association with activity. The lambs consumed heather at approximately 20% of their dry matter intake, which was sufficient to exhibit significant anthelmintic effects via a reduction in total egg output (P = 0.007), compared to hay-fed lambs; the magnitude of the reduction over time in heather fed lambs was almost 10-fold compared to control lambs. Negative effects on production were shown, as heather-fed lambs weighed 6% less than hay-fed lambs (P < 0.001), even though dry matter intake (DMI) of heather increased over time. D. flagrans supplementation lowered larval recovery in the faeces of infected lambs by 31.8% (P = 0.003), although no interactions between feeding heather and D. flagrans were observed (P = 0.337). There was no significant correlation between PA, or other polyphenol subgroups in the diet and egg output, which suggests that any association between heather feeding and anthelmintic effect is not simply and directly attributable to the measured polyphenols. The level of heather intake in this study showed no antagonistic effects on D. flagrans , demonstrating the methods can be used in combination, but provide no additive effect on overall anthelmintic efficacies. In conclusion, heather feeding can assist to reduce egg outputs in infected sheep, but at 20% of DMI negative effects on lamb performance can be expected which may outweigh any antiparasitic benefits. • Heather intake at 20% of DMI reduced gastrointestinal nematode daily egg output. • Adult worm counts were not affected by heather consumption in infected lambs. • Lambs on the heather diet suffered performance costs shown by lower bodyweight. • Supplementation with Duddingtonia flagrans reduced larval recovery in faeces. [ABSTRACT FROM AUTHOR]

Copyright of Botanica Serbica is the property of University of Belgrade, Institute of Botany & Botanical Garden Jevremovac and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Room temperature ionic liquids are novel solvents with the specific properties that makes them of interest for application for extraction for a wide range of compounds. In this work extraction efficiency of flavonoids from heather flowers using ionic liquids based on imidazolium cation were evaluated and compared with organic solvents. It was found that the anion of ionic liquid significantly influence the extraction yields. Flavonoid content as well as antioxidant activity based on radical scavenging on 1,1-diphenul-2-pirylhydrazyl radicals and cupric reducing antioxidant capacity increased in the order: [Bmim]PF6 < [Bmim]BF4 < [Bmim]Cl. The obtained extraction yield using [Bmim]Cl were higher than reported for 60% ethanol and ethyl acetate under similar conditions, thus, may be helpful for better utilization of heather flowers as the potential pharmaceutical and nutraceutical ingredients. [ABSTRACT FROM AUTHOR]

The distribution of nine chloroplast DNA haplotypes in four insular North-Atlantic and four European coastal Atlantic populations of Calluna vulgaris in the glacial zone of the range has been analyzed in comparison with that in six marginal southern populations in the nonglacial zone of the Atlantic and Mediterranean regions. As a result, two hypothetical Pleistocene refugia (HPRs) for this C. vulgaris population group have been revealed, one in the Cévennes mountain range and the other in the Southern Alps (Trento). Judging from the 1-FST value, it has been found that the group of populations in the glacial Atlantic zone and adjacent European coastal Atlantic region is genetically similar to the HPR in the Cévennes at a highly significant level (p ≥ 0.999) and less similar to the HPR in Trento; however, it differs significantly from other Mediterranean and Atlantic populations. It has been concluded that the most probable hypothetical Pleistocene refugium for the recent C. vulgaris populations of the northeastern Atlantic and European coastal Atlantic regions was in the west of the Mediterranean, in the Cévennes, while the additional refugium was in the Southern Alps. Possible directions of the postglacial dispersal and recolonization of habitats by C. vulgaris populations from the western Mediterranean to the northeast of the Atlantic and to Scandinavia have been revealed. [ABSTRACT FROM AUTHOR]

• We built models for above-ground biomass from percentage cover of ericaceous shrubs. • We also provide a novel model application estimating cervid forage. • Easily available or measurable metrics significantly improve our models. • Percentage cover, spruce basal area and fertility are important in our predictions. • High potential for implementation of models in forestry management support systems. Common understory vegetation species such as the ericaceous shrubs bilberry (Vaccinium myrtillus), cowberry (V. vitis-idaea) and heather (Calluna vulgaris), are key forage plant species for moose and other large herbivores, as well as fulfilling many additional ecosystem functions and services. Here we developed models to predict above-ground biomass of these ericaceous species in coniferous forests, using data on their percentage cover, height, and different stand characteristics. We also built models to understand how the aforementioned variables affect the proportion of the shrubs commonly utilized as forage by large herbivores. We found that the percentage cover of shrubs was the most important explanatory variable when predicting above-ground biomass, explaining 51%, 47% and 71% of the variation (marginal R2) in bilberry, cowberry and heather biomass, respectively. By adding ramet height to the model with percentage cover, the variation explained increased to 77% for bilberry, 75% for cowberry and 87% for heather. The best outcome for candidate models was obtained by adding stand site index and spruce basal area to the model, improving the variation explained in bilberry to 83%, to 81% for cowberry, and 91% for heather. When modelling the proportion of the shrubs commonly utilized as forage by large herbivores, stand site index and spruce basal area often played important roles. Some of the best fitting models for forage biomass explained 51% of the variation in bilberry, 59% in cowberry and 30% in heather. Site location did not have a major role in improving the variability explained in either type of model, which indicated the applicability of the models regardless of study location. Our models therefore have a high potential to be implemented in forestry decision support systems. Their inclusion should provide better large-scale estimations of forage resources, aiding forest management, and thereby taking an important step forward to determine the ecosystem carrying capacity of large herbivores. [ABSTRACT FROM AUTHOR]

Although the collection of the Hungarian Natural History Museum (Budapest) does not house any specimens of Coleophora juncicolella Stainton, 1851 from Hungary, several works have treated this species as resident since its fi rst report in 1952. We found this species at three new localities in 2017 and 2018. Th e case is illustrated and a map of distribution in Hungary is given. With 2 fi gures. [ABSTRACT FROM AUTHOR]

Variation in the structure of ground fuels, i.e. the moss and litter (M/L) layer, may be an important control on fire severity in heather moorlands and thus influence vegetation regeneration and soil carbon dynamics. We completed experimental fires in a Calluna vulgaris -dominated heathland to study the role of the M/L layer in determining (i) fire-induced temperature pulses into the soil and (ii) post-fire soil thermal dynamics. Manually removing the M/L layer before burning increased fire-induced soil heating, both at the soil surface and 2 cm below. Burnt plots where the M/L layer was removed simulated the fuel structure after high severity fires where ground fuels are consumed but the soil does not ignite. Where the M/L layer was manually removed, either before or after the fire, post-fire soil thermal dynamics showed larger diurnal and seasonal variation, as well as similar patterns to those observed after wildfires, compared to burnt plots where the M/L layer was not manipulated. We used soil temperatures to explore potential changes in post-fire soil respiration. Simulated high fire severity (where the M/L layer was manually removed) increased estimates of soil respiration in warm months. With projected fire regimes shifting towards higher severity fires, our results can help land managers develop strategies to balance ecosystem services in Calluna -dominated habitats. [ABSTRACT FROM AUTHOR]

Calluna vulgaris, Carex rigida, Deschampsia flexuosa, Nardus stricta and Vaccinium myrtillus are abundant in the vegetation of mountainous areas in Northern and Central Europe. Knowledge of their ability to accumulate increased amounts of metals could be useful in the evaluation of environmental pollution in the alpine tundra of high mountains. Additionally, this investigation may contribute to understanding the rate and direction of recent vegetation change in Karkonosze and similar types of environments. Our investigation revealed that Carex rigida, C. vulgaris and V. myrtillus contain excessive Mn concentrations in shoots with the highest BF for this element compared to the BFs of other elements. C. rigida, with Cu, Mn and Zn concentrations exceeding the toxicity thresholds for plants, seems to be the best metal phytoaccumulator for Nardus stricta grasslands Carici ( rigidae)- Nardetum (CrN) and alpine heathlands Carici ( rigidae)- Festucetum airoidis (CrFa) associations in the Karkonosze. Based on relevant BFs >1, it can be stated that the following plant available metals were transferred to shoots: Cu, Mn and Ni by C. vulgaris; Cd, Cu, Mn, Ni and Zn by C. rigida; Cd, Cu, Mn, Ni and Zn by D. flexuosa; Cu, Mn, Ni and Zn by N. stricta and Cu, Mn and Zn by V. myrtillus. [ABSTRACT FROM AUTHOR]

Understanding the response of soil respiration to climate variability is critical to formulate realistic predictions of future carbon (C) fluxes under different climate change scenarios. There is growing evidence that the influence of long-term climate variability in C fluxes from terrestrial ecosystems is modulated by adjustments in the aboveground-belowground links. Here, we studied the inter-annual variability in soil respiration from a wet shrubland going through successional change in North Wales (UK) during 13 years. We hypothesised that the decline in plant productivity observed over a decade would result in a decrease in the apparent sensitivity of soil respiration to soil temperature, and that rainfall variability would explain a significant fraction of the inter-annual variability in plant productivity, and consequently, in soil respiration, due to excess-water constraining nutrient availability for plants. As hypothesised, there were parallel decreases between plant productivity and annual and summer CO emissions over the 13-year period. Soil temperatures did not follow a similar trend, which resulted in a decline in the apparent sensitivity of soil respiration to soil temperature (apparent Q values decreased from 9.4 to 2.8). Contrary to our second hypothesis, summer maximum air temperature rather than rainfall was the climate variable with the greatest influence on aboveground biomass and annual cumulative respiration. Since summer air temperature and rainfall were positively associated, the greatest annual respiration values were recorded during years of high rainfall. The results suggest that adjustments in plant productivity might have a critical role in determining the long-term-sensitivity of soil respiration to changing climate conditions. [ABSTRACT FROM AUTHOR]

Background and Aims: As different plant species support different soil communities, assessment of climate change impacts on soil communities must consider how these impacts depend on the vegetation. We investigate soil community responses to global change under different co-occurring plant species. Methods: In a heathland FACE-experiment, we modelled projected global changes by increasing atmospheric CO concentration (to 510 ppm) and soil temperature by 1 °C at 2 cm depth (with night-time reflectance curtains) and reducing summer precipitation for 2-5 weeks annually (with rain-out curtains). We assessed nematode community trophic composition and bacterial and fungal abundance in soil under the dominant plant species Calluna vulgaris and Deschampsia flexuosa in the spring, 10 months after the last experimental drought period. Results: Fungal dominance increased relative to bacterial under elevated CO. Similarly, elevated CO increased abundance of fungivorous nematodes relative to bacterivorous nematodes. Decreased precipitation did not affect the abundances of microorganisms or nematodes, and there were only few effects of warming. Fungivorous nematodes dominated under C. vulgaris, whereas bacterivorous nematodes were relatively more abundant under D. flexuosa. Abundances of plant feeding and omnivorous/predatory nematodes were higher under D. flexuosa than under C. vulgaris. Conclusions: This supports the hypothesis that more carbon will flow through fungal than bacterial channels when below-ground allocation of photosynthetically-derived C increases without a corresponding soil nitrogen increase. Further, as different plant species are associated with distinct belowground decomposer communities, vegetation shifts induced by future CO and climate regimes will also shift belowground communities with consequences for decomposition dynamics. [ABSTRACT FROM AUTHOR]

Anthropogenic deposition of reactive nitrogen (N) has increased during the 20th century, and is considered an important driver of shifts in ecosystem functions and biodiversity loss. The objective of the present study was to identify those ecosystem functions that best evidence a target ecosystem’s sensitivity to N deposition, taking coastal heathlands as an example. We conducted a three-year field experiment in heathlands of the island Fehmarn (Baltic Sea, North Germany), which currently are subject to a background deposition of 9 kg N ha −1 yr −1 . We experimentally applied six levels of N fertilisation (application of 0, 2.5, 5, 10, 20, and 50 kg N ha −1 yr −1 ), and quantified the growth responses of different plant species of different life forms (dwarf shrubs, graminoids, bryophytes, lichens) as well as shifts in the C:N ratios of plant tissue and humus horizons. For an applicability of the experimental findings (in terms of heathland management and critical load assessment) fertilisation effects on response variables were visualised by calculating the treatment ‘effect sizes’. The current year’s shoot increment of the dominant dwarf shrub Calluna vulgaris proved to be the most sensitive indicator to N fertilisation. Shoot increment significantly responded to additions of ≥ 5 kg N ha −1 yr −1 already in the first year, whereas flower formation of Calluna vulgaris increased only in the high-N treatments. Similarly, tissue C:N ratios of vascular plants ( Calluna vulgaris and the graminoids Carex arenaria and Festuca ovina agg.) only decreased in the highest N treatments (50 and 20 kg N ha −1 yr −1 , respectively). In contrast, tissue C:N ratios of cryptogams responded more quickly and sensitively than vascular plants. For example, Cladonia spp. tissue C:N ratios responded to N additions ≥ 5 kg N ha −1 yr −1 in the second study year. After three years we observed an increase in cover of graminoids and a corresponding decrease of cryptogams at N fertilisation rates of ≥ 10 kg N ha −1 yr −1 . Soil C:N ratios proved to be an inappropriate indicator for N fertilisation at least within our three-year study period. Although current critical N loads for heathlands (10−20 kg N ha −1 yr −1 ) were confirmed in our experiment, the immediate and highly sensitive response of the current year’s shoots of Calluna vulgaris suggests that at least some ecosystem functions (e.g. dwarf shrub growth) also might respond to low (i.e. < 10 kg N ha −1 yr −1 ) but chronic inputs of N. [ABSTRACT FROM AUTHOR]

The dominant plant species of European heathlands Calluna vulgaris is considered vulnerable to drought and enhanced nitrogen (N) loads. However, impacts may vary across the distribution range of Calluna heathlands. We tested the hypothesis that Calluna of southern and eastern marginal populations (MP) are more resistant to drought events than plants of central populations (CP), and that this is mainly due to trait differences such as biomass allocation patterns. Furthermore, we hypothesised that N fertilisation can offset differences in drought susceptibility between CP and MP. We conducted a full-factorial 2-year greenhouse experiment with Calluna plants of CP and MP and quantified growth responses in terms of biomass production, allocation and tissue δC signatures. Biomass production, shoot-root ratios and tissue δC values of 1-year-old plants were higher for CP than for MP, indicating a higher drought susceptibility of CP. These trait differences were not observed for 2-year-old plants. N fertilisation increased shoot-root ratios of 1- and 2-year-old plants and across populations due to a stimulation of the aboveground biomass allocation. As a consequence, population-related differences in drought susceptibility were offset for N-fertilised plants. We concluded that Calluna plants originating from different populations developed adaptive traits to local climates, which determined their drought sensitivity. However, the higher drought resistance of MP can be attenuated by an N-induced increase in shoot-root ratios. This suggests that analyses on plant growth responses to global change should include multi-factor approaches with a focus on different populations throughout a species' distribution range. [ABSTRACT FROM AUTHOR]

Heathland in the UK, and parts of mainland Europe, is being managed increasingly by landowners and statutory conservation bodies e.g., Natural England, using cattle grazing which is often referred to as 'conservation grazing' in an attempt to justify its use in the absence of any detailed prior research into its actual benefits for wildlife species whose individual habitat requirements are likely to vary. Over four years, between 2010 and 2013, cattle were excluded from six hectares of lowland heath that had been subject to annual summer cattle grazing between May 1997 and autumn 2009 and in which reptile numbers had been monitored annually since 1997. Changes in smooth snake (Coronella austriaca) numbers were recorded annually in the ungrazed area and in a four hectare area of heathland adjacent to it that continued to be grazed. The number of individual smooth snakes, and the total number of smooth snake captures, were significantly higher in the ungrazed heath than the grazed heath and were associated with increased habitat structure, resulting principally from tall heathers and grasses. The results of the study suggest that the use of cattle grazing as a management tool on lowland heath is detrimental to smooth snake populations and that their recovery, following the cessation of grazing, may take many years. [ABSTRACT FROM AUTHOR]

Ecosystem carbon (C) accrual and storage can be enhanced by removing large herbivores as well as by the fertilizing effect of atmospheric nitrogen (N) deposition. These drivers are unlikely to operate independently, yet their combined effect on aboveground and belowground C storage remains largely unexplored. We sampled inside and outside 19 upland grazing exclosures, established for up to 80 years, across an N deposition gradient (5-24 kg N ha−1 yr−1) and found that herbivore removal increased aboveground plant C stocks, particularly in moss, shrubs and litter. Soil C storage increased with atmospheric N deposition, and this was moderated by the presence or absence of herbivores. In exclosures receiving above 11 kg N ha−1 year−1, herbivore removal resulted in increased soil C stocks. This effect was typically greater for exclosures dominated by dwarf shrubs ( Calluna vulgaris) than by grasses ( Molinia caerulea). The same pattern was observed for ecosystem C storage. We used our data to predict C storage for a scenario of removing all large herbivores from UK heathlands. Predictions were made considering herbivore removal only (ignoring N deposition) and the combined effects of herbivore removal and current N deposition rates. Predictions including N deposition resulted in a smaller increase in UK heathland C storage than predictions using herbivore removal only. This finding was driven by the fact that the majority of UK heathlands receive low N deposition rates at which herbivore removal has little effect on C storage. Our findings demonstrate the crucial link between herbivory by large mammals and atmospheric N deposition, and this interaction needs to be considered in models of biogeochemical cycling. [ABSTRACT FROM AUTHOR]

The aroma profiles of thirteen different honey samples from four botanical origins: heather ( Calluna vulgaris ), raspberry ( Rubus idaeus ), rape ( Brassica napus ), alder buckthorn ( Frangula alnus ) and the blossoms of the four corresponding flowers were investigated to find odour-active compounds exclusively representing specific honeys based on odour-active compounds from the blossoms. Gas-chromatography–mass spectrometry (GC–MS) and gas-chromatography–olfactometry were used to determine and identify the odour-active compounds. Data was analysed using agglomerative hierarchical clustering and correspondence analysis. Honeys from the same botanical origin clustered together; however, none of the identified compounds were exclusive to a particular honey/blossom combination. Heather honey had the flavour profile most different to the others. Isophorone and 2-methylbutyric acid were found only in heather honeys. Heather honey was characterised by having more “sweet” and “candy-like” notes, raspberry honeys had more “green” notes, while alder buckthorn had more “honey” and “floral” notes. [ABSTRACT FROM AUTHOR]

Background:An understanding of the effects of red deer on bryophyte and lichen communities in wet heath and bog vegetation typical of northwest Scotland is important so that land managers can make more informed decisions concerning deer numbers. Aims:To compare various measures of cryptogam species diversity inside and outside a number of established deer exclosures at the Letterewe and Little Gruinard estates, Wester Ross, Scotland. Methods:Species cover data were recorded from 192 2 m × 2 m quadrats allocated to 32 blocks and assigned to nine exclosures of different ages with due attention to randomisation. Linear mixed effects models were fitted to the data. Results:In the short to medium term there was no significant difference in cryptogam dominance, diversity and species richness on either side of the exclosures. However,Cladonialichens responded to a lack of trampling and were significantly more abundant inside exclosures. GreaterCalluna vulgariscover in the absence of a large herbivore is likely to have created conditions that promote the growth ofSphagnum capillifoliumssp.rubellumand this in turn increased the habitat available for several liverworts. Conclusions:The upper limit of deer numbers deemed appropriate for reducing loss ofCallunacover in wet heath vegetation is set too high to prevent impact on important cryptogam communities. [ABSTRACT FROM AUTHOR]

This study seeks to investigate the role of Calluna vulgaris canopy height in the CO 2 balance of ombrotrophic peatlands to address what implications this relationship may have for management of these peatlands for maximal carbon storage. This study uses a monthly dataset of CO 2 flux and associated environmental variables gathered from three localities in the South Pennines and the Peak District National Park of northern England between 2007 and 2010, covering a range of C. vulgaris canopy heights. It was found that both gross fluxes of CO 2 (ecosystem respiration and photosynthesis) were modelled best by models incorporating a dependence on canopy height. Ecosystem respiration was positively correlated and photosynthesis was negatively correlated to canopy height. It was found that as canopy height increases, the amount of photosynthesis per unit respiration decreased and thus that net ecosystem exchange became more positive. Despite the relationship between the gross fluxes and canopy height, models of net ecosystem exchange suggested that there was no canopy height at which blanket peat dominated by C. vulgaris would be a net annual sink of CO 2 . This was due to the relatively deep water tables at the sites which served to enhance ecosystem respiration. Looking at the dataset as a whole, for a 10 cm increase in canopy height there was a median increase of 0.829 ± 0.583 g CO 2 m 2 d −1 in net CO 2 flux, with considerable seasonal variation. Managers interested in minimising CO 2 losses from blanket peat should note that C. vulgaris on blanket peat in the areas studied is predicted to be a net source of CO 2 to the atmosphere for all canopy heights. As such, vegetation management away from C. vulgaris dominance is recommended to improve the functioning of these bogs. If vegetation management away from heather on climatically marginal blanket peat is infeasible then managers should avoid taller canopies, where day time photosynthesis is almost always less than day time respiration. [ABSTRACT FROM AUTHOR]

Highlights: [•] The effect of UVB on HUVECs pretreated with Calluna vulgaris (Cv) extract was studied. [•] UVB exposure increased MDA and γ-H2AX levels, induced apoptosis and activated NF-κB. [•] 2.5μg GAE/mlCv improved antioxidant defense, reduced DNA lesions and cell death. [•] 7.5μg GAE/ml Cv was prooxidant, increased DNA lesions, cell death, activated NF-κB. [•] The photochemopreventive effect of Cv extract on UVB exposed HUVECs was dose dependent. [Copyright &y& Elsevier]

Background and Aims Across their range, widely distributed species are exposed to a variety of climatic and other environmental conditions, and accordingly may display variation in life history strategies. For seed germination in cold climates, two contrasting responses to variation in winter temperature have been documented: first, an increased ability to germinate at low temperatures (cold tolerance) as winter temperatures decrease, and secondly a reduced ability to germinate at low temperatures (cold avoidance) that concentrates germination towards the warmer parts of the season. Methods Germination responses were tested for Calluna vulgaris, the dominant species of European heathlands, from ten populations collected along broad-scale bioclimatic gradients (latitude, altitude) in Norway, covering a substantial fraction of the species' climatic range. Incubation treatments varied from 10 to 25 °C, and germination performance across populations was analysed in relation to temperature conditions at the seed collection locations. Key Results Seeds from all populations germinated rapidly and to high final percentages under the warmer incubation temperatures. Under low incubation temperatures, cold-climate populations had significantly lower germination rates and percentages than warm-climate populations. While germination rates and percentages also increased with seed mass, seed mass did not vary along the climatic gradients, and therefore did not explain the variation in germination responses. Conclusions Variation in germination responses among Calluna populations was consistent with increased temperature requirements for germination towards colder climates, indicating a cold-avoidance germination strategy conditional on the temperature at the seeds' origin. Along a gradient of increasing temperatures this suggests a shift in selection pressures on germination from climatic adversity (i.e. low temperatures and potential frost risk in early or late season) to competitive performance and better exploitation of the entire growing season. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present study was to evaluate the in vitro effects of heather (Ericaceae) phenolic extracts on the abomasal nematodes Teladorsagia circumcincta and Haemonchus contortus. Extracts of three heather species (Calluna vulgaris, Erica cinerea, Erica umbellata and a balanced mixture of all three) were tested in vitro on different development stages of T. circumcincta (eggs, infective larvae and adult worms) and H. contortus (eggs and infective larvae) using an egg hatching assay (EHA), a larval exsheathment inhibition assay (LEIA) and an adult motility inhibition assay (AMIA). The egg hatching rate was measured after incubation with heather extracts for 48h at 25°C. Ensheathed infective larvae were incubated for 3h at 20°C with heather extracts. Artificial exsheathment was induced in vitro by adding hypochloride solution to the larval suspension. The progress of exsheathment over time was measured by repeated observations at 10-min (T. circumcincta) and 20-min (H. contortus) intervals for 60min. Adult T. circumcincta worms were obtained from two donor goats and incubated with the extracts at 37°C for 3 days in 48-well multiwell plates. Worm motility was measured at 0, 19, 24, 43, 48, 67 and 72h. The extracts were tested at concentrations of 75, 150, 300, 600 and 1200μg/mL. Incubation with E. cinerea, E. umbellata and mixed heather extracts had a significant (P <0.01) dose-dependent effect on T. circumcincta egg hatching. H. contortus egg hatching was significantly (P <0.01) inhibited only by the E. cinerea extract. All extracts had a significant (P <0.01) dose-dependent effect on the exsheathment of T. circumcincta and H. contortus infective larvae. The incubation with all heather extracts induced a reduction in adult T. circumcincta motility compared to the control, although significant (P <0.05) differences were only found at the highest concentration (1200μg/mL). The effect of the mixed extract was significant at all concentrations and significant effects were also observed for C. vulgaris and E. umbellata at 600μg/mL. These results show anthelmintic properties of heather phenolic extracts against T. circumcincta and H. contort, thus confirming observations from previous in vivo studies. [Copyright &y& Elsevier]

Highlights: [•] Moorland vegetation on peat is subject to both prescribed burning and wildfire. [•] Propagule banks were measured at two moorlands to assess regeneration potential. [•] Deep litter accumulated seeds and prevented transfer to underlying peat. [•] Long-rotation burns favoured Calluna vulgaris and Sphagnum propagule frequency. [•] We advise burning at two rotations; short for conserving diversity in vegetation and long for conserving propagule banks. [ABSTRACT FROM AUTHOR]

Background and aims: Shrublands are ecosystems vulnerable to climate changes, with key functions such as carbon storage likely to be affected. In dwarf shrublands dominated by Calluna vulgaris, the aboveground carbon allocation is associated with community age and phase of development. As the Calluna community grows older, a shift to net biomass loss occurs and it was hypothesized this would result in carbon stock increases within the soil. Methods: The interaction of community age with ecosystem carbon stocks was investigated through a chronosequence study on three Calluna communities, aged 11, 18 and 27 years. Results: Aboveground Calluna carbon stock increased significantly from the 11 year community (0.73 kg C m) to the 18 year community (1.11 kg C m) but did not significantly change from 18 to 27 years (1.0 kg C m), indicating a net carbon gain that corresponded with the growth phase of the Calluna plants. Moss was also found to be a relatively large contributor to aboveground carbon stock (e.g. 30 % in the Young community). Moss has often been excluded in aboveground assessments on Calluna heathlands which may have led to previous stock underestimation. Belowground carbon stocks to 25 cm were six to nine times greater than in the aboveground pools. For example in the Young community, 8 % of the carbon stock was located aboveground, 35 % in the organic layer and 55 % in the mineral soil. Conclusions: Increased heathland age resulted in increased aboveground carbon stock until peak production was reached at approximately 18 years of age. However, the proportionally large belowground carbon stock eclipsed any aboveground effect when total carbon stocks were considered. The investigation emphasized both the importance of including the mineral soil in sampling programs and of consider all major species, such as bryophytes, and vegetation age in carbon stock assessments. [ABSTRACT FROM AUTHOR]

Analysis of geographic variation of chloroplast DNA in the eastern European and western Siberian (Tobol) groups of Calluna vulgaris populations isolated from each other for a long period of time has revealed distinct differentiation between them. It has been shown that three populations growing in the Russian Plain and Karelia share two haplotypes characteristic of central Europe, while three Tobol populations contain one haplotype F occurring in Sweden. These results confirm the hypothesis of genetic divergence between the Tobol and eastern European groups of C. vulgaris populations. [ABSTRACT FROM AUTHOR]

Increases in the emissions and associated atmospheric deposition of nitrogen (N) have the potential to cause significant changes to the structure and function of N-limited ecosystems. Here, we present the results of a long-term (13 year) experiment assessing the impacts of N addition (30 kg ha−1 yr−1) on a UK lowland heathland under a wide range of environmental conditions, including the occurrence of prolonged natural drought episodes and a severe summer fire. Our findings indicate that elevated N deposition results in large, persistent effects on Calluna growth, phenology and chemistry, severe suppression of understorey lichen flora and changes in soil biogeochemistry. Growing season rainfall was found to be a strong driver of inter-annual variation in Calluna growth and, although interactions between N and rainfall for shoot growth were not significant until the later phase of the experiment, N addition exacerbated the extent of drought injury to Calluna shoots following naturally occurring droughts in 2003 and 2009. Following a severe wildfire at the experimental site in 2006, heathland regeneration dynamics were significantly affected by N, with a greater abundance of pioneering moss species and suppression of the lichen flora in plots receiving N additions. Significant interactions between climate and N were also apparent post fire, with the characteristic stimulation in Calluna growth in +N plots suppressed during dry years. Carbon (C) and N budgets demonstrate large increases in both above- and below-ground stocks of these elements in N-treated plots prior to the fire, despite higher levels of soil microbial activity and organic matter turnover. Although much of the organic material was removed during the fire, pre-existing treatment differences were still evident following the burn. Post fire accumulation of below-ground C and N stocks was increased rapidly in N-treated plots, highlighting the role of N deposition in ecosystem C sequestration. [ABSTRACT FROM AUTHOR]

Studies on the soil seed banks of fallow lands of different ages were carried out on poor soil abandoned fields and in a fresh coniferous forest in north-eastern Poland. The size and diversity of seed banks was studied with the seedling emergence method. Species abundance (I), density (ii), number of species from different biological groups (iii) and distribution and mean LI value (iv) were analysed as the function of fallow land age. It was found that: (i) species diversity, number of species and ln of density are linear declining function of the fallow land age; (ii) for approx. 25 years the share of diaspores of identified species groups has been relatively similar. Seed banks of 40-50-year-old fallow lands are dominated by Calluna vulgaris, while the seed bank of the old fresh coniferous forest is dominated by dicotyledonous perennials and grasses; (iii) within the first 50 years of succession the persistence of seed banks measured by the Longevity Index increases gradually. [ABSTRACT FROM AUTHOR]

We analysed growth strategies (biomass allocation, nutrient sequestration and allocation) of heather (Calluna vulgaris) and purple moor-grass (Molinia caerulea) seedlings in monocultures and mixtures in relation to N, P, and N + P fertilisation in a greenhouse experiment in order to simulate a heath’s pioneer phase under high airborne nitrogen (N) loads. N fertilisation increased the total biomass of both species in monocultures. In mixtures, M. caerulea sequestered about 65% of the N applied, while C. vulgaris suffered from N shortage (halving of the total biomass). Thus, in mixtures only M. caerulea will benefit from airborne N loads, and competition will become increasingly asymmetric with increasing N availability. Our results demonstrate that the heath’s pioneer phase is the crucial tipping point at which the competitive vigour of M. caerulea (high belowground allocation, efficient use of belowground resources, shortened reproductive cycles) induces a shift to dominance of grasses under increased N availability. [Copyright &y& Elsevier]

Abstract: European lowland heaths have declined by up to 80% due to land use change and lack of management. There has been considerable research into the restoration of this threatened habitat. However, long-term outcomes of restoration are poorly understood, especially in situations where past agricultural land use imposes severe constraints on community re-assembly. In 1989 a large-scale experiment was established to examine the effectiveness of five treatments to restore heathland on formerly productive grassland: (i) natural regeneration; (ii) herbicide application to facilitate regeneration; (iii) cultivation and application of seed-rich heathland vegetation; (iv) soil removal and incorporation of heathland topsoil; and (v) heathland translocation. After 17years the pH of the unamended agricultural soil remained significantly higher than that of the adjacent heathland. All treatments showed different trajectories of vegetation change in the long-term. Natural colonisation by heathland species was slow due to seed limitation, resulting in formation of an acid grassland community. Heathland community assembly was not facilitated by destruction of the initial grassland with herbicide. Incorporation of topsoil had an intermediate effect on pH reduction. This may explain the subsequent failure of the plant community to assemble in the anticipated proportions, and the dominance of leguminous scrub species (Ulex spp.). Turf translocation was effective in reducing pH to the required range and restoring the heathland community in the long-term. However, this technique should only be considered as a means of ‘rescue’ when habitat destruction is otherwise unavoidable. The only practical and sustainable means of increasing heathland extent on former farmland is the application of seed-bearing vegetation cut as part of routine management. However, this technique needs refining in order to establish the full range of characteristic heathland species. [Copyright &y& Elsevier]

In the present study, we analyze the fate of airborne nitrogen in heathland ecosystems (NW Germany) by means of a N tracer experiment. Our objective was to quantify N sequestration and N allocation patterns in an ecosystem that is naturally limited by N, but that has been exposed to airborne N inputs exceeding critical loads for more than 3 decades. We hypothesized that the system has a tendency towards N saturation, which should be indicated by low N sequestration and high N leaching. We analyzed N partitioning (aboveground biomass and soil horizons) and investigated N leaching over 2 years following a N tracer pulse addition. N tracer recovery was 90% and 76% in the first and second year, respectively. Contrary to our expectations, more than 99% of the tracer recovered was sequestered in the biomass and soil, while leaching losses were <0.05% after 2 years. Mosses were the most important short-term sink for N (64% recovery in the first year), followed by the organic layer. In the second year, the moss layer developed from a sink to a source (23% losses), and soil compartments were the most important sink (gains of 11.2% in the second year). Low N recovery in the current year's shoots of Calluna vulgaris (<2%) indicated minor availability of N tracer sequestered in the organic layer. N partitioning patterns showed that the investigated heaths still have conservative N cycling, even after several decades of high N loads. This finding is mainly attributable to the high immobilization capacities for N of podzols in soil compartments. In the long term, the podzol A- and B-horizons in particular may immobilize considerable amounts of incoming N. Since N compounds of these horizons are not readily bio-available, podzols have a high potential to withdraw airborne N from the system's N cycle. [ABSTRACT FROM AUTHOR]

Abstract: To understand the implications of atmospheric nitrogen deposition on carbon turnover in peatlands, we conducted a 13C pulse labeling experiment on Calluna vulgaris and Eriophorum vaginatum already receiving long-term (5 years) amendments of 56 kg N ha−1 y−1 as ammonium or nitrate. We examined shoot tissue retention, net ecosystem respiration returns of the 13C pulse, and soil porewater DOC content under the two species. 13C fixation in Eriophorum leaves was enhanced with nitrogen addition and doubled with nitrate supply. This newly fixed C appeared to be relocated below-ground faster with nitrogen fertilization as respiration returns were unaffected by N inputs. By contrast, increases in 13C fixation were not observed in Calluna. Instead, net ecosystem respiration rates over Calluna increased with N fertilization. There was no significant label incorporation into DOC, suggesting a conservative strategy of peatland vegetation regarding allocation of C through root exudation. Greater concentrations of total DOC were identified with nitrate addition in Calluna. Given the long-term nature of the experiment and the high N inputs, the overall impacts of nitrogen amendments on the fate of recently synthesized C in Eriophorum and Calluna in this ombrotrophic peatland were surprisingly more moderate than originally hypothesized. This may be due to N being effectively retained within the bryophyte layer, thus limiting, and delaying the onset of, below-ground effects. [ABSTRACT FROM AUTHOR]

ording to the EU Habitats Directive, heathlands are a semi-natural habitat type of community interest. This status aims at conserving these habitats, especially where and when they are threatened by various changes, including natural vegetation succession. We present results of a study of the dynamics of a typical dry heathland plot located in the Fontainebleau massif (France). An exhaustive observation of vegetation changes were made on this area of four hectares between 2000 and 2008, employing a spatial approach. We recorded the expansion of Molinia caerulea (L.) Moench at the expense of Ericaceae. The potential future vegetation of the site was modelled using Markov chains coupled to a GIS programme. This model predicted a gradual change in the floristic composition of heathland in favour of M. caerulea at the expense of Calluna vulgaris (L.) Hull and Erica tetralix L., and the expansion of Pinus sylvestris L. The study demonstrates how spatial methods can contribute to the design of reliable management methods of habitats such as the heathlands. [ABSTRACT FROM AUTHOR]

Abstract: Heather moorlands are internationally important ecosystems that are highly sensitive to eutrophication and acidification by reactive atmospheric nitrogen (N) deposition. We used a long-term experiment simulating wet-deposition of N on heather moorland to identify potential bio-indicators of N deposition. These indicators were subsequently employed in a survey covering a N deposition gradient ranging from approximately 7 to 31kg N ha−1 yr−1, at selected sites throughout the UK. In this regional survey litter phenol oxidase activity and bryophyte species richness were negatively associated with N deposition. Calluna vulgaris N:P ratios and litter extractable N were positively correlated with N deposition. The use of the suite of four bio-indicators has the potential to provide rapid assessment of the extent of N saturation of heather moorland sites and moorland ecosystem functioning, and has significant advantages over reliance on single measures such as soil N status or an individual bio-indicator species. [Copyright &y& Elsevier]