Conservation of montane willow scrub in Scotland

Summary

The community known as montane willow scrub has been almost totally destroyed in Scotland by human activities. The species of montane willows are not regarded as threatened by the conventional criteria, but the continued effects of grazing, combined with their sparse distribution in suboptimal habitat and dioecious habit, suggest that the long term threat to some species may have been underestimated. Conservation measures are needed urgently if we are to restore areas of montane willow scrub. It will be necessary to use fencing to provide protection from grazing, and also it may well be necessary to do some planting to provide enough individuals for effective pollination and regeneration to occur.     

Patterns of clonal diversity in three species of sub-arctic willow (Salix lanata, Salix lapponum and Salix herbacea)

Sub-arctic willow scrub is an endangered habitat in Britain, and typically occurs on steep crags inaccessible to grazing animals. These willows can reproduce both sexually and asexually, although the relative importance of each is unknown. Knowledge of reproductive mode is important for the design of grazing management and restoration programmes. Accordingly, clonality was assessed in the largest stand of sub-arctic willow scrub in the UK, focusing on Salix lanata and S. lapponum. Little evidence of clonal growth was detected; most individuals possessed distinct multi-locus genotypes. Thus despite the capacity for vegetative reproduction, and seedlings being rarely observed, sexual reproduction is the predominant means of perpetuation and dispersal at this site. We also examined clonal growth in a common willow species (Salix herbacea) that occupies a different habitat type (exposed mountain tops and ridges). Multiple individuals shared identical genotypes up to 7 m apart, suggesting an important role for clonal growth in local patch formation in this species.     

Vegetation influence on ectomycorrhizal inoculum Available to sub-arctic willow (Salix lapponum L.) planted in an upland Site

Summary

Restoration of scrub and woodland in deforested upland sites is an important conservation activity. However, little is known about the mycorrhizal colonisation potential of upland soils or the factors that influence the distribution of mycorrhizal inoculum. We investigated the effect of existing vegetation on mycorrhizal colonisation potential for a sub-arctic willow (Salix lapponum) by planting uninoculated cuttings into plotsrepresenting two upland habitats with either grassand herbs (‘grass’) or Vaccinium myrtillus (‘vaccinium’) and assessing mycorrhizal colonisation after 14 months using morphological and molecular techniques. From 40 willow cuttings (20 in each habitat), DNA sequences of rive ectomycorrhizal (EcM) fungal taxa were recovered: Laccaria proxima, Thelephora terrestris, Hebeloma sp., ‘Thelephoraceae sp.’ and ‘Pezizales sp.’. Cuttings in the ‘grass’ habitat were dominated by Laccaria proxima and ‘Pezizales sp.’ and in the ‘vaccinium’ habitat by Thelephora terrestris which was absent from the ‘grass’ habitat. There were no significant differences between habitats in frequency of EcM inoculum (overall percentage of cuttings colonised = 70%) or colonisation potential (overall mean percentage of root tips colonised per cutting = 20 %). These data suggest that the mycorrhizal colonisation potential and diversity of fungi available to willow in these upland soils are low and planted willow may benefit from inoculum enhancement.     

A new species of Lathyrus L. (Fabaceae) from Central Apennine (Italy)

Abstract

Lathyrus apenninus, from beech woods margins and scrub in the Central Apennine (Italy), is described as a species new to science. The relationship of L. apenninus with L. linifolius, which it had been confused with, is briefly discussed.     

Genetic characterization of Salix alba L. and Salix fragilis L. by means of different PCR-derived marker systems

Abstract

Salix alba L. and Salix fragilis L. are two closely related willow species whose phenotypic features, showing a large and continuous variation, have a low diagnostic value for identifying pure species and interspecific hybrids. In this paper, the effectiveness of different multilocus PCR-based molecular markers, such as I-SSRs, RAPDs and AFLPs in detecting genetic polymorphisms able to discriminate the two willow species was evaluated by analysing a set of 12 reference samples. Three genetic similarity indexes, Dice, Jaccard and Simple Matching coefficient, were used for all possible pairwise comparisons of individuals, revealing the same trend of variation within and between species when different marker systems were used. Cluster analysis, based on Dice genetic similarity coefficient, clustered the individuals of S. alba and S. fragilis into two distinct subgroups, indicating that the gene pools are well differentiated. Moreover, a number of private alleles for each marker system allowed the discrimination of the two species because always present only in one of the two. The utility of different marker systems in discriminating willow species was evaluated by the Polymorphism Information Content (PIC) and the Marker Index (MI) parameters. The variation of Dice's indexes obtained from a different number of experiments in relation to the marker systems is discussed.     

Birds in willow short-rotation coppice compared to other arable crops in central England and a review of bird census data from energy crops in the UK

We present the results of spring and winter surveys of birds using 22 willow short-rotation coppice (SRC) fields and 22 paired arable or grassland controls over a 5 year period in central and northern England. The study sites were linked to the first commercial wood-fuelled electricity plant in Yorkshire and were managed commercially. We use the findings of this study, in the context of other work on birds in energy crops, to suggest how birds may be affected by commercial cropping of SRC or energy grasses on UK farmland. For willow SRC, most existing farmland species were not completely displaced by SRC cropping. Even farmland specialists such as Skylark Alauda arvensis used cut SRC fields. Some species characteristic of scrub and wood-type habitats were attracted onto farmland by SRC. Birds were more abundant in hedgerows next to SRC than in those adjoining arable or grass. The interior of large SRC plots contained fewer birds than the edge-zone (< 50 m). In winter, the same resident species occured in SRC as the summer, plus winter migrants such as Snipe Gallinago gallinago and Fieldfare Turdus pilaris . Overall, more individuals and species were recorded in and around SRC than equivalent arable or grassland throughout the year. Yellow Wagtail Motacilla flava and certain locally occurring farmland specialists may be displaced by SRC plantations. Equivalent census data for energy grasses in the UK are not available. The impact of large regional energy crop developments on birds is not known. We do not know if species commonly recorded in these crops survive and breed well so population effects are unknown. However SRC crops are often weedy and insect rich and hence have potential as foraging habitats in summer and winter. The scope for agri-environment schemes to include energy crops is discussed.     

Selective stripping of rowan (Sorbus aucuparia L.) bark by cattle in North-east Scotland

Summary

During winter 1973–4 beef cattle removed bark selectively and extensively from rowan growing in two Aberdeenshire woods. Some bark was also taken from Norway spruce and willow, but damage to all other species, including ash, beech, birch, gean, larch, Scots pine and sycamore, was negligible. In other woodlands utilised by cattle in this area bark-stripping was either less severe or absent. Possible causes for the bark-stripping are discussed. The rowan bark was not distinctive in cover, species of epiphytic lichen or inorganic composition, except perhaps for magnesium.     

Factors contributing to the seasonal occurrence of the willow leaf beetle Plagiodera versicolora

We conducted a 3-year study of a natural population of the willow leaf beetle Plagiodera versicolora (Coleoptera: Chrysomelidae) on a river bank of the Inukami River, Shiga, central Japan, where four willow species (Salix chaenomeloides, S. eriocarpa, S. integra, and S. serissaefolia) occur sympatrically. Our survey showed that: (1) at the study site, the abundance of P. versicolora greatly varied among years and among willow species; (2) adult abundance changed seasonally with species-specific patterns on different willow species; and (3) the dispersal-settlement of adults had the most pronounced effects on the seasonal population growth rate of P. versicolora. Factors affecting these results were discussed.     

Two new remarkable Nolinaceae from Central Mexico

Two new species of Nolinaceae are described and illustrated. The first is a ponytail palm,Beaucarnea compacta, occuring in xerophytic scrub in the Sierra Madre Oriental near Atarjea, Guanajuato. The second new species isCalibanus glassianus, adding the second species to the genusCalibanus. This new species is found in the transition between tropical deciduous forest to subontane scrub in the Sierra Madre Oriental near Xichú, Guanajuato.

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Se describen e ilustran dos nuevas especies de Nolinaceae. La primera es una pata de elefante o palma petacona,Beaucarnea compacta. Se distribuye en matorrales xerófitos de la Sierra madre Oriental cerca de Atarjea, Guanajuato. La segunda nueva especie esCalibanus glassianus, que adiciona una especie más al géneroCalibanus. Esta nueva especie se encuentra en la transición de bosques tropicales caducifolios con matorrales xerófilos de la sierra Madre Oriental en los alrededores de Xichú, Guanajuato.

     

Seasonal abundance of Tuberolachnus salignus and its effect on flowering of host willows of varying susceptibility

The giant willow aphid Tuberolachnus salignus Gmelin is a large phloem-feeding insect which colonizes the stems of willow trees. This aphid is a new invasive species in New Zealand and there is limited knowledge of its inter-annual population patterns and the damage it can cause to willow hosts. Our study investigated the T. salignus population dynamics and its effects on the flowering parameters of fifteen willow species and hybrids in a field trial. The aphid population levels were found to vary among the willow species and hybrids. Based on the aphid population levels, the willow species and hybrids were classified as resistant, moderately resistant, susceptible or highly susceptible. T. salignus infestation had no effect on the flowering of resistant and moderately resistant willows, but significantly delayed the flowering time, extended the flowering duration, and decreased the catkin length in susceptible species and hybrids. Interestingly, aphid infestation was found to increase the catkin number and total floral output of some willow species and hybrids. It can be concluded that aphid populations and their effects on flowering are host-specific, with large differences between resistant and susceptible host plants.     

Misdiagnosis of scrub typhus as hemorrhagic fever with renal syndrome and potential co-infection of both diseases in patients in Shandong Province,China, 2013–2014

BackgroundScrub typhus, caused by Orientia tsutsugamushi, an obligate intracellular gram-negative bacterium, along with hemorrhagic fever with renal syndrome (HFRS), caused by hantaviruses, are natural-focus infectious diseases prevalent in Shandong Province, China. Both diseases have similar clinical manifestations in certain disease stages and similar epidemic seasons, which has caused difficulties for physicians in distinguishing them. The aim of this study was to investigate whether misdiagnosis of scrub typhus as HFRS occurred in patients in Shandong Province.MethodsSerum samples (N = 112) of clinically suspected HFRS patients from 2013 to 2014 in Shandong Province were analyzed with enzyme-linked immunosorbent assay (ELISA) for antibodies to both hantavirus and Orientia tsutsugamushi.ResultsELISA showed that 56.3% (63/112) and 8.0% (9/112) of clinically suspected HFRS patients were IgM antibody positive to hantavirus and O. tsutsugamushi, respectively. Among the hantavirus IgM antibody positive patients, 7.9% (5/63) were also IgM antibody positive to O. tsutsugamushi. Among the hantavirus IgM antibody negative sera, 8.2% (4/49) of sera were positive to O. tsutsugamushi.ConclusionsWe concluded that some scrub typhus patients were misdiagnosed as HFRS and co-infection of scrub typhus and HFRS might exist in China. Due to the different treatments for scrub typhus and HFRS, physicians should carefully differentiate between scrub typhus and HFRS and consider administering anti-rickettsia antibiotics if treatment for HFRS alone does not work.     

Biomass Harvest from Natural Willow Rings around Prairie Wetlands

The study followed the harvest of natural willow from three wetlands using a prototype modified agricultural round baler nicknamed a Bio-Baler. The study reports fuel characteristics and combustion testing of biomass harvested from natural willow rings. Composition of native willow species in the harvested willow rings was determined. We specifically measured regrowth of the biomass and number of regenerated stems per stump 1 year after harvest to determine how different willow species responded to mechanical biomass cutting with the Bio-Baler. The results of combustion testing for the natural willow were essentially similar to those with “conventional” wood chips or planted willows. The ash content was approximately 1.65%, slightly lower than for planted willow plantations. The calorific value of the natural willow was 19.6 MJ kg^?1 (dry basis) similar to what is expected for wood and planted willow. Four Salix species (Salix bebbiana Sarg., Salix petiolaris Sm., Salix eriocephala Michx., and Salix discolor Muhl) were identified in the willow rings. Stem biomass increased for all species except S. bebbiana after willow was harvested with the Bio-Baler. Overall, willow regeneration was not affected by mechanical harvesting compared to hand cutting. Regenerated stem density was 93 stems per square meter for mechanically harvested stumps compared to 105 stems per square meter for hand-pruned stumps. Based on the results, biomass harvested from natural willow rings has acceptable fuel characteristics when compared to purpose-grown willows and mechanical harvest with a Bio-Baler does not have a negative effect on willow regeneration.     

Two new Marina (Leguminosae) from the southern Baja California peninsula, Mexico

Marina victoriae andM. brevis are newly described species from the southern Baja California peninsula, Mexico. The former is a perennial herb locally abundant in the eroded hillsides at the foothills of Sierra de la Victoria, where an oak woodland and a dry tropical forest meet. The latter is an elusive ephemeral inhabiting a narrow strip of land between the mangroves and the desert scrub on an island in the Gulf of California. These two new species belong to the seriesChrysorrhizae, a group native to the Gulf of California basin.     

Seasonal vartadoosln the nutrtent content of carpets of Acrocladium cuspidatum (Hedw.)Lindb.

Abstract

1. Seasonal variations in the percentaae of potassium, sodium, calcium and phosphorus in the current season's growth segment of Acrocladium cuspidatum at three different habitats are presented.

2. The results show that the nutrient content of the moss carpet varies with time of year and also between habitats. For this reason comparisons between the nutrient content of moss carpets from different habitats are unlikely to be valid unless made at the same time of year or during comparable stages in the annual growth cycle of the species concerned.

3. In conditions where the moss becomes inundated by natural waters having a high concentration of calcium ions, the moss accumulates calcium to abnormally high levels.

4. Comparison of the nutrient content of the moss on open downland and under scrub shows a greater accumulation of potassium in the moss carpet of the scrub habitat. The monthly differences between the potassium contents from the two sites are positively correlated with the monthly rainfall as are also the actual percentages of potassium present in the moss carpet beneath the scrub.     

Spatiotemporal Dynamics of Scrub Typhus Transmission in Mainland China, 2006-2014

BackgroundScrub typhus is endemic in the Asia-Pacific region including China, and the number of reported cases has increased dramatically in the past decade. However, the spatial-temporal dynamics and the potential risk factors in transmission of scrub typhus in mainland China have yet to be characterized.ObjectiveThis study aims to explore the spatiotemporal dynamics of reported scrub typhus cases in mainland China between January 2006 and December 2014, to detect the location of high risk spatiotemporal clusters of scrub typhus cases, and identify the potential risk factors affecting the re-emergence of the disease.MethodMonthly cases of scrub typhus reported at the county level between 2006 and 2014 were obtained from the Chinese Center for Diseases Control and Prevention. Time-series analyses, spatiotemporal cluster analyses, and spatial scan statistics were used to explore the characteristics of the scrub typhus incidence. To explore the association between scrub typhus incidence and environmental variables panel Poisson regression analysis was conducted.ResultsDuring the time period between 2006 and 2014 a total of 54,558 scrub typhus cases were reported in mainland China, which grew exponentially. The majority of cases were reported each year between July and November, with peak incidence during October every year. The spatiotemporal dynamics of scrub typhus varied over the study period with high-risk clusters identified in southwest, southern, and middle-eastern part of China. Scrub typhus incidence was positively correlated with the percentage of shrub and meteorological variables including temperature and precipitation.ConclusionsThe results of this study demonstrate areas in China that could be targeted with public health interventions to mitigate the growing threat of scrub typhus in the country.     

The burden of scrub typhus in India: A systematic review

BackgroundScrub typhus, a vector-borne zoonotic infection caused by the bacteria Orientia tsutsugamushi, is one of the most common and clinically important rickettsial infections worldwide. An estimated one million cases occur annually with a high case fatality rate. Although scrub typhus is a major public health threat in India, the burden and distribution remains unclear. We aimed to estimate the burden of scrub typhus in India.MethodologyWe performed a systematic review of published literature on scrub typhus from India to extract information on epidemiology, morbidity, and mortality. Important databases were searched using keywords and appropriate combinations. We identified observational, interventional, and population-based studies and extracted the data to evaluate the number of cases diagnosed using serology or PCR and the number of deaths due to scrub typhus. We conducted a systematic narrative synthesis to summarize included studies.Principal findingsIn the last decade, there were 18,781 confirmed scrub typhus cases reported in 138 hospital-based studies and two community-based studies. IgM ELISA was used in 122 studies to confirm the cases in majority (89%). The proportion of scrub typhus among acute undifferentiated febrile illness (AUFI) studies was 25.3%, and community seroprevalence was 34.2%. Ninety studies had data published on multiple organ involvement out of which 17.4% of cases had multiple organ dysfunction syndromes, 20.4% patients required ICU admission, and 19.1% needed ventilation. The overall case-fatality rate was 6.3%, and the mortality among those with multi-organ dysfunction syndrome was as high as 38.9%.Conclusion/significanceScrub typhus, a common acute febrile illness in India causing severe morbidity, accounts for a large number of deaths. The burden of the disease has been underappreciated. Early diagnosis and prompt treatment can significantly reduce complications and mortality. Establishing good surveillance and instituting appropriate control measures are urgently needed.     

Establishment of Moose Browse on Four Growth Media on a Proposed Mine Site in Southcentral Alaska

The objective of this study was to evaluate seven woody plant species on four growth media for their potential contribution to moose habitat and establishment of viable plant communities on a proposed mine site in southcentral Alaska. Populus balsamifera (balsam poplar), Salix alaxensis (feltleaf willow), S. barclayi (Barclay willow), S. bebbiana (Bebb willow), Alnus tenuifolia (thinleaf alder), Betula papyrifera (paper birch), and Picea glauca (white spruce) were selected for their functions in moose habitat, ease of propagation, and presence in the existing native vegetation. Three native soils were selected for biological characteristics such as different potential to form mycorrhizae and to regenerate local plant species, both of which are governed partly by existing vegetation. The fourth growth medium, glacial till or overburden, was expected to have little or no biological activity. A mining disturbance was simulated on three sites by removing existing vegetation from the plots, stripping the native soils, and then spreading these soil materials over the respective study plots. Rooted cuttings of the Salicaceae and nursery seedlings of the other species were planted in each of the four growth media. Height and survival of all plant species were greater on the three soil media than on the glacial till during the second and third years. Percentage of ectomycorrhizal infection on transplants was similar among growth media, although lower ectomycorrhizal infection occurred on volunteers in grassland soils than in the other growth media. Browsable plants were produced within three years on the disturbed native soils but not on the glacial till.     

The impacts of pollination mode,plant characteristics and local density on the reproductive success of a scarce plant species, <Emphasis Type="Italic">Salix arbuscula</Emphasis>

Pollination failure represents one stage at which sexual reproduction of plants may be limited. It is therefore important to understand the pollination mechanism of the plant and how this may be affected by plant and population characteristics. This study examined the reproductive biology of a scarce montane willow species, Salix arbuscula, as part of a programme to determine ecological strategies for the conservation of montane willow scrub, an endangered habitat in the UK. The relative importance of insect and wind pollination, and the role of plant characteristics including plant size, catkin length, number of flowers and local density in determining reproductive success (number of fruit set) were investigated in three populations. Insect exclosures were used to determine the pollination mechanism. Our results suggest that S. arbuscula is predominantly insect-pollinated. In naturally pollinated plants, catkins with a higher proportion of ripe fruit were longer. Plants with more than two males in the local area and unbrowsed plants had a higher proportion of ripe fruit per catkin. The extent of wind pollination was very low, but differed between populations. The success of wind-only pollination was dependent on the number of males nearby, indicating that local density is more important in this type of pollination. Pollination mechanism and fruit set varied between the three populations observed, demonstrating the importance of multi-site comparisons. The number of males in the surrounding area had a positive effect on fruit set in both types of pollination, suggesting that Allee effects are likely to be operating in this species.