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Background: Gastrointestinal nematode (GIN) control is traditionally achieved with the use of anthelmintic drugs, however due to regulations in organic farming and the rise in anthelmintic resistance, alternatives are sought after. A promising alternative is the use of bioactive plant feeding due to the presence of plant secondary metabolites (PSMs) such as proanthocyanidins (PAs). This study focussed on the perennial shrub heather (Ericaceae family), a plant rich in PAs, highly abundant across Europe and with previously demonstrated anthelmintic potential. Methods: In vitro assays were used to investigate heather's anthelmintic efficacy against egg hatching and larval motility. Heather samples were collected from five European countries across two seasons, and extracts were tested against two GIN species: Teladorsagia circumcincta and Trichostrongylus colubriformis. Polyphenol group-specific ultraperformance liquid chromatography-tandem mass spectrometry analysis was performed to identify relevant polyphenol subgroups present, including the PA concentration and size and ratio of the subunits. Partial least squares analysis was performed to associate efficacy with variation in PSM composition. Results: Heather extracts reduced egg hatching of both GIN species in a dose-dependent manner by up to 100%, while three extracts at the highest concentration (10 mg/ml) reduced larval motility to levels that were not significantly different from dead larvae controls. PAs, particularly the procyanidin type, and flavonol derivatives were associated with anthelmintic activity, and the particular subgroup of polyphenols associated with the efficacy was dependent on the GIN species and life stage. Conclusions: Our results provide in vitro evidence that heather, a widely available plant often managed as a weed in grazing systems, has anthelmintic properties attributed to various groups of PSMs and could contribute to sustainable GIN control in ruminant production systems across Europe. [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]

Quantitative reconstructions of past land- cover are necessary for research into the processes involved in climate-human-land interactions. We present the first temporally continuous pollen-based land-cover reconstruction for Europe over the Holocene (last 11,700 cal yr BP). We describe how vegetation cover has been quantified from pollen records at a 1° x 1° spatial scale using the 'Regional Estimates of VEgetation Abundance from Large Sites' (REVEALS) model. REVEALS has been applied to 1128 pollen records across Europe and part of the Eastern Mediterranean-Black Sea-Caspian-Corridor (30°-75° N, 25° W-50° E) to reconstruct the cover of 31 plant taxa assigned to 12 plant functional types (PFTs) and three land-cover types (LCTs). A new synthesis of relative pollen productivities (RPPs) available for European plant taxa was performed for this reconstruction. It includes > 1 RPP values for 39 taxa, and single values for 15 taxa (total of 54 taxa). As an illustration, we present maps of the results for five taxa (Calluna vulgaris, Cerealia-t, Picea abies, Quercus deciduous and Quercus evergreen) and three LCTs (open land (OL), evergreen trees (ET) and summer-green trees (ST)) for 8 selected time windows. We discuss the reliability of the REVEALS reconstructions and issues related to the interpretation of the results in terms of landscape openness and human-induced vegetation change. We then describe the current use of this reconstruction and its future potential utility and development. The REVEALS data presented here can be downloaded from https://doi.pangaea.de/10.1594/PANGAEA.937075?format= html#download. [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.)

In this article, we examined the indicative value of a relationship between two non-pollen palynomorphs (NPPs), fungal HdV-10, related to the presence of Calluna vulgaris, and HdV-31A, which is testate amoeba – Archerella flavum. Both are frequently present on slides designated for pollen analysis, prepared from Sphagnum peat. We analysed three profiles from three extensive ombrotrophic peatlands in northern Poland, in which the content of testate amoebae (TA) was examined and TA-inferred depth to the water table (DWT) was reconstructed. The new analysis of palynological samples regarding NPPs revealed that strong increases in HdV-10 content were mostly simultaneous to HdV-31A declines. However, the relations between both types were not statistically significant. The rapid increases in HdV-10, despite the fact that this type of conidiospores is related to drier habitats on peatlands, were tentatively interpreted as an indicator of rapid rises in the water table level which, in consequence, might have stimulated the production of these spores by fungi. In addition, a negative correlation between HdV-31A and Arcella discoides and positive one, but weaker, in case of HdV-10 (attributed by some authors to species Trichocladium opacum (Corda) S Hughes) and A. discoides show a link between mutual fluctuations of both NPPs and hydrological instabilities on peatland. The Bagno Kusowo bog, the westernmost peatland subjected to the study, displayed an intriguing agreement between the presence of peat sections with strong increases in HdV-10 and cold climate events affecting Europe. Our study reveals that counting even a limited number of NPP types during the standard pollen analysis of Sphagnum peat may support the interpretation of results, especially, in cases when the investigation lacks testate amoeba analysis. When the reconstruction of TA-inferred DWT is provided, it may introduce additional information about the patterns of hydrological dynamics. [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.)

Geographic variation and differentiation of the chloroplast DNA haplotypes and morpho-anatomical leaf parameters were assessed in a number of eastern European groups of Calluna vulgaris (L.) Hull. populations and in the Pritobolien group of populations of this species in Western Siberia, which have long been isolated from the European populations. Sharply pronounced genetic and phenotypic distances and their gradients between the Pritobolien and European population groups were revealed. These distances were many times higher than those between the relatively homogeneous eastern European groups. The data obtained generally supported the hypothesis on the phenogenetic divergence of the Pritobolien marginal populations of C. vulgaris from the European, probably at the subspecies level. [ABSTRACT FROM AUTHOR]

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]

There has been a significant loss in the UK, and elsewhere in Europe, of moorland dominated by heather Calluna vulgaris. One response to this has been the initiation of moorland vegetation restoration projects. Heather moorland has distinct assemblages of invertebrates and the ability of these to colonise newly created habitat patches has not previously been experimentally tested. We established a dispersal and colonisation experiment by transplanting C. vulgaris-dominated turfs within grassland at different distances (up to 40 m) from heather moorland vegetation. Hemiptera were cleared from these turfs by the use of an insecticide and were sampled 1 year later to investigate re-colonisation rates. Hemiptera assemblages on transplanted turfs were most dissimilar to those of heather moor at the greatest distances of these turfs from heather moor. Colonisation rates of heathland-indicator Hemiptera declined exponentially with distance. The number of individual heathland-indicator Hemiptera was higher on turfs 5 and 10 m from heather moor than on turfs transplanted back into the heather moor, possibly due to a crowding effect. Our findings indicate that moorland Hemiptera assemblages may be limited by dispersal ability. We recommend that moorland restoration schemes should be prioritised on ground as close as possible to existing heather moors. [ABSTRACT FROM AUTHOR]

Many areas of heathland in Europe have seen a decline in the area and condition of Calluna vulgaris (heather)-dominated vegetation, with subsequent declines in the associated faunal interest. Grazing, alongside burning, is still the predominant means of managing heathland vegetation, and, therefore, it is by manipulating this management that cost-effective improvements in vegetation condition can be made. This paper investigates the suitability of different grazing treatments for rehabilitating degraded ‘dry heath’. Treatments varied in the intensity (0–1.9 sheep ha−1 year−1) and timing (summer vs. winter) of sheep grazing. These treatments were compared with the behaviour of vegetation outside the fenced area kept under the previous management (open access all year round). As rabbits were common on the site, fences were erected to prevent access to the sheep grazed plots. Vegetation composition remained stable outside the fenced area, whilst all the fenced treatments showed a decrease in heather utilisation and an increase in the relative frequency of heather over the 5 years of the experiment. The increase was in proportion to the reduction in stocking rate, with only slow increases in relative frequency observed in the high grazing treatments (winter and summer). Other species that benefited from reducing grazing included Empetrum nigrum and Vaccinium myrtillus, whilst declines were observed for Agrostis capillaris and total monocotyledonous species. Only small overall differences were observed between the winter low, summer low and no sheep grazing treatments. However, a difference in response was present between the sheep exclosures and the sheep+rabbit exclosures, indicating that rabbits were having a noticeable effect on heather recovery at this site. On this degraded ‘dry heath’ system, imposing a reduction in stocking density improved the condition of the dwarf shrubs present and reduced the grass component of the vegetation. There was little effect of the timing of grazing, such that a reduction in sheep numbers to 0.8/0.9 sheep ha−1 year−1, to give utilisation levels of below 20%, can achieve the desired result of improving vegetation condition whilst still achieving some economic return from grazing. However, the wide range of ‘sustainable’ stocking densities for different heathland systems highlights the need to base effective management on measured utilisation rather than on stock numbers. [Copyright &y& Elsevier]

Increasing dominance of grass species such as Deschampsia flexuosa on lowland dry heathlands is a major problem for land managers. This problem is especially acute in north-west Europe where replacement of dwarf-shrubs by grasses has been linked to high levels of nitrogen deposition. Interactions between Calluna vulgaris and D. flexuosa were examined using pot experiments under a variety of watering (drought vs. no drought), nitrogen addition (10 vs. 50 kg N ha-1 yr-1) and soil type (peaty vs. sandy) regimes. Two experiments using identical replacement series designs were used to investigate interactions between these two species at the seedling and young plant stage. Response of the two species to the environmental variables was different for seedlings and young plants. In the seedling experiment D. flexuosa responded significantly to soil type only, with greater cover on peaty soil than on sandy soil after 6 months. C. vulgaris germination showed a significant response to watering regime, with fewer seedlings in plots that had a drought treatment imposed. When the experiment was repeated using young plants of C. vulgaris and D. flexuosa both species responded significantly to soil type only. Height, % cover and shoot biomass of both species were greater when grown in peaty soil than when grown in sandy soil. Watering and nitrogen addition had few significant effects. Species interactions were mainly one-way. C. vulgaris biomass yield was reduced when grown in mixture with D. flexuosa, whilst D. flexuosa yield was unaffected by the presence of C. vulgaris. The yield density curve for D. flexuosa indicated that intra-specific competition was occurring at planting densities above 29 plants m-2 whilst this was not seen for C. vulgaris. The effect of soil type on species interactions was also investigated. C. vulgaris was best able to compete with D. flexuosa on sandy soils where the shoot biomass ratio was greatest (C. vulgaris:D. flexuosa= 1:4.4). Differences in the responses of these species to the environmental variables investigated may help to explain heathland vegetation changes seen under field conditions. [ABSTRACT FROM AUTHOR]

1. Lowland Calluna -dominated heathlands are a high priority for conservation in Europe. As an anthropogenic subclimax community they require regular management intervention to maintain their conservation interest. 2. Increasingly, Calluna is disappearing from lowland heathlands and being replaced by grasses, especially in the Netherlands and more recently in south-east England. While Calluna is highly competitive over much of its life cycle, its competitive ability is reduced during the regeneration phase that follows the death of stands or results from management activity. 3. We examined the influence of five factors on regeneration of vegetation in gaps in two broadly similar lowland dry heaths over a 3-year period. These were: geographical location (combining a variety of environmental contrasts); dominant species (Calluna or grasses); management techniques; gap size; and seed source availability. 4. Site location had the greatest effect on patterns of regeneration. Regeneration on the Wirral (north-west England) was faster and more dominated by Calluna than regeneration in Breckland (south-east England), which was dominated by other species including grasses and annual plants. Addition of Calluna seed at the Breckland site failed to increase Calluna cover. It was concluded that climatic or other environmental factors were the most probable cause of poor regeneration. 5. Cover of grasses in regenerating areas was greatest in Breckland, where Deschampsia was able to establish in all gaps where there was a seed source (either in the surrounding vegetation or applied as a treatment). On the Wirral, Deschampsia establishment was limited, even in gaps where a seed source was applied. 6. This work has implications for the conservation management of heathlands, which currently follows a standard prescription throughout the UK. It is suggested that management regimes should be tailored to suit the conditions prevailing at individual sites as regeneration dynamics... [ABSTRACT FROM AUTHOR]

Despite the importance of atmospheric methane as a potent greenhouse gas and the significant contribution from ruminant enteric fermentation on methane emissions at a global scale, little effort has been made to consider the influence that different plant-based natural diets have on methane emissions in grazing systems. Heathland is an ericaceous dwarf-shrub-dominated habitat widespread across the northern hemisphere, in Europe, provides valuable ecosystem services in areas with poor soils, such as water flow regulation, land-based carbon skin, energy reservoir and habitat of key game species. We (i) measured methane emissions from red deer (Cervus elaphus) and sheep (Ovis aries) fed mixed diets of natural grass plus ericaceous species (either Calluna vulgaris or Vaccinium myrtillus) using open-circuit respiration chambers; and (ii) modelled the results to estimate methane emissions from red deer and sheep populations inhabiting heathland habitats across Europe under different scenarios of grass-based mixed diets with varying proportions of ericaceous species. Our results indicated that methane emissions per unit of digestible organic matter intake decreased as the proportion of ericaceous species in diet increased, but this relationship was complex because of the significant interaction between the proportion of ericaceous species in the diet and digestible organic matter intake. According to our estimates red deer and sheep populations across European heathlands produce 129.7 kt·y -1 methane (se = 1.79) based on a hypothetical grass-ericaceous species mixed diet containing 30% of ericaceous species; this is 0.5% of total methane emissions from human activity across Europe (24,755 kt·y -1 ), and a reduction in methane emissions of 63.8 kt·y -1 against the same deer and sheep populations, if assumed to consume a grass-only diet. We suggest the implementation of carbon credits as a measure to value the relevance of heathland systems to promote biodiversity and its potential contribution to reduce methane emissions in ruminant grazing systems., Competing Interests: Declaration of competing interest No conflict of interest, (Copyright © 2020. Published by Elsevier B.V.)