Types of Scottish bog vegetation

Summary

The main types of ombrotrophic mire vegetation in Scotland are described with reference to selected mire sites of national importance. The range of variation is controlled by two main environmental gradients, climate and altitude. In particular the degree of oceanicity is crucial, influencing both the vegetation and the hydro-morphology of individual mires. The framework described provided the basis for selection of 31 nationally important mire sites in Scotland identified in the Nature Conservation Review in 1977. Protection of these sites has been successful, except for two sites now afforested. Current threats to Scottish peatlands mainly relate to lowland raised mires.     

Rumex aquaticus L. at Loch Lomondside

Summary

A new alliance of spring vegetation dominated by the leafy liverwort Anthelia julacea is described from the montane regions of Britain. It is distinguished floristically and ecologically from similar alpine late snow bed communities in Scotland and Scandinavia. The classificatory position of the stands of this vegetation type is discussed with reference to continental and British systems and it is concluded that the erection of a new alliance is justified on floristic grounds.     

Distribution and extent of unimproved lowland grassland National Vegetation Classification (NVC) types in Scotland

Summary

National Vegetation Classification (NVC) data from surveys of Scottish unimproved lowland grasslands were reviewed. The surveys dated from 1980 to 2000. The mapped area of each lowland grassland NVC type was measured or, where vegetation maps were not of sufficient quality, estimated. These measurements and estimates were summed to give the total recorded area of each lowland grassland NVC type. An estimate of the total area likely to occur throughout Scotland was made for the more thoroughly recorded lowland grassland NVC types.

The data from this review has been used to create Scottish Natural Heritage's Lowland Grassland Database, containing details of all lowland grassland sites recorded by the grassland surveys, their grid reference, conservation status, site area, surveyor, date of survey, NVC lowland grassland types present and their areas. Council Area, old local authority District and SNH Area are also included.

A total of 8700 ha of unimproved lowland grassland NVC types (excluding coastal grasslands) has been recorded in Scotland. This habitat is semi-natural and of high conservation value.

The total area of unimproved lowland grassland in Scotland is estimated to be in the order of 30,000 ha.     

Lichen-rich pinewood,Cladonia ciliata-Pinus sylvestris community in north-eastern Scotland

Summary

Ground dominated by Cladonia lichens of the sub-genus Cladina was found locally on pinewood floors on sandy or gravelly soils in north-eastern Scotland. Most sites are under mature or old planted Scots pine, Pinus sylvestris, but some in younger plantations and a few in native pinewood. Nearly all are in areas of fairly dry climate, and all are in open situations with exposure to light and wind. The vegetation, prior to 1990 not a well recognized feature of Scottish pinewoods, is distinguished in this paper as a separate community, the Cladonia ciliata — Pinus sylvestris Community. It is part of the class Vaccinio-Piceetea and resembles the lichen-rich coniferous forests in the circumpolar boreal zone, but in Scotland occurs at the extreme climatic limit of this type of vegetation. Many stands are vulnerable to trampling and land-use change, and some have little protection against such environmental vicissitudes.     

Genetic insights into the evolution of Scots pine,Pinus sylvestris L., in Scotland

Summary

Present day populations of native Scots pine contain a wealth of genetic variation. The arrangement of this variation within and among populations has been influenced by a number of processes in the past. These include patterns of recolonization of Scotland after glaciation, gene flow among populations, and natural selection acting at both a regional and local scale. By analyzing present day patterns of genetic variation, insights into past evolution can be obtained. Suitable analysis of genetic variation for monoterpenes, enzymes, mitochondrial DNA and quantitative characters such as growth rate and phenology in native pine indicate two origins for Scottish populations, substantial adaptive divergence from continental populations, and the presence of local adaptation within Scotland. The implications for conservation and future research are addressed.     

Illecebrum verticillatum L. in the outer Hebrides

Summary

Scottish habitats are here reviewed in a European context. Examples are selected in order to identify those recognisable as distinctively Scottish as well as others related to Scandinavian or European counterparts. The paper begins with a resumé of the main environmental influences in Scotland, then describes examples of habitats almost unique to, or best represented in Scotland. This is followed by reference to some distinctively western versions of more widely distributed habitats, and others corresponding to related types elsewhere. The bearing of this on site selection for nature conservation is discussed. Hitherto, in the UK selection for National Nature Reserves and Sites of Special Scientific Interest has been based largely on the criteria listed in A Nature Conservation Review (Ratcliffe, 1977). It is important, however, also to review Scottish habitats in a European context, as attempted in this paper. In making proposals (now approaching completion) for Special Areas of Conservation, to be recommended by the UK Government for adoption by the European Commission, it is now our duty to include not only habitats for which we have special responsibility because they are unique to or best represented in Scotland, or have distinctively western features, but also sufficient examples of all the main European types occurring in our country.

Nomenclature of British flowering plants and ferns follows Stace (1991).     

I. Introduction

Background: Past research and ecological theory supports the hypothesis that alpine plants should be predominantly clonal, long-lived and reproduce by seed infrequently.

Aims: To challenge the entrenched view that alpine seedling establishment is uncommon and perhaps unsuccessful in maintaining alpine plant populations.

Methods: We looked for patterns in seedling establishment across a stress gradient of alpine sites and tested the notion that natural seedling recruitment would be reduced at higher altitudes due to a combination of stressful environmental conditions such as frosts, wind and extended snow cover.

Results: Seedlings were common at all study sites and there was a partial trend in mean seedling density with altitude. Seedling emergence was best predicted by a combination of altitude, plant litter and soil wilting point. Many seedlings survived to become established plants (37–61%) but there was no significant relationship between establishment and altitude. There was low similarity between the seedling flora and the standing vegetation, suggesting that patterns in seedling establishment are unlikely to be driving the patterns in the standing vegetation assemblage.

Conclusions: Although Australian alpine species predominantly reproduce vegetatively, this study shows that many plants depend on recruitment from seed in order to become established.     

Notes on the Scottish flora

Background: The degradation of alpine meadows on the Qinghai-Tibetan Plateau (QTP) has an impact on vegetation recruitment from seedlings and ramets.

Aims: Understanding the relative contribution of recruitment by seedling and ramet in alpine meadows is for the ecological restoration of degraded grasslands on the QTP.

Methods: An experiment was conducted to investigate seedling and ramet densities, species composition and their relationships with standing vegetation in plots representative of non-degraded (ND), lightly (LD), moderately (MD) and severely degraded (SD) alpine meadows.

Results: With increasing degradation and the reduction in vegetation cover, the number of seedlings and ramets declined. The proportion of young plants arising from seedlings was low, with the majority of species reproducing clonally. The establishment of seedlings of forbs in SD meadows led to species-rich, forb-dominant vegetation in these areas.

Conclusions: LD and MD meadows appear to be able to be managed by reduced grazing for the restoration of grass- and sedge-dominated pastures. In contrast, restoration of SD meadows will require additional intervention, such as of seeding and weed eradication.     

Conserving Scotland's raised bogs

Summary

Raised bog was always a relatively rare habitat in Scotland and, being mainly found in lowland areas, the habitat has had a long history of land-use and exploitation associated with it. Today, raised bogs are considered as one of Britain's rarest and most endangered habitats. As a consequence the Scottish Wildlife Trust ran a conservation programme (the Scottish Raised Bog Conservation Project) between 1993 and 1995 to set up a strategy which could conserve the remaining bogs. A major landcover survey executed under the auspices of the project revealed widespread damage although 9% of the resource remained in a ‘near-natural’ state. However, the continuing cumulative effects of centuries of small scale activities and the effects of past and present air-pollution places all sites under considerable threat. One way to counter such threats is to enact positive conservation management on sites. To date, most work has concerned vegetation and hydrological management on the mire surface. Initial analyses of monitoring programmes suggest this type of conservation management is having little impact across the whole site. It is suggested that more comprehensive programmes of management should now be undertaken to restore the hydrological system of the whole site including the surrounding lagg fens.     

The census and selective service

Abstract

A number of studies are reviewed to show that the mean level of measured intelligence in Scotland is approximately three to four IQ points lower than that in England. These results are a striking contrast with another set of findings showing that in the nineteenth century Scotland had a greater proportional output of people of intellectual distinction than did England. Evidence on Scottish‐English differences in education, parental attention, and per capita income suggests that none of these factors can explain the difference in mean IQ. It is suggested that the principal cause of the reduced mean intelligence in Scotland lies in the selective emigration of the more intelligent, and evidence is reviewed to show that this emigration has occurred for at least a century.     

Habitat associations and breeding success of the Chaffinch Fringilla coelebs

Capsule Population trends for Chaffinch on farmland are unlikely to be explained by their preference for non-crop habitats alone.

Aims To investigate the importance of non-cropped habitats for Chaffinch territory distribution, breeding success and foraging habitat selection in Scottish farmland.

Methods Territory distribution, nesting success and foraging behaviour of adults feeding chicks at the nest were recorded and related to habitat composition on two Scottish lowland farms.

Results Higher Chaffinch territory densities were associated with the presence of hedgerows, trees and grass leys, whereas lower densities were found adjacent to winter Barley. Nests were predominantly located in conifer trees and hedgerows. Trees were selected preferentially for foraging. Poor breeding success was detected in nests associated with cereal crops and wider field margins. Farmland in Scotland supported much lower territory densities than in England.

Conclusion Chaffinches rely predominantly on non-cropped habitats for territory establishment, nesting and foraging habitats. Differences in habitat composition between England and Scotland may explain differences in territory densities. However, the Chaffinch's preference for non-crop habitats is unlikely to explain its population trends alone. Immigration from other habitats and/or a decrease in inter-specific competition for resources may also have contributed to the increase in the national farmland Chaffinch population.     

The coastal fringe: Habitats threatened through global warming

Summary

Vegetation of the coastal fringe of Scotland (sea cliffs, dunes and salt marshes out to the depth limit of benthic algae and seagrasses) was subject to repeated cycles of glaciation, with low values of temperature, sea level and atmospheric CO₂, alternating with interglacials with higher temperature, sea level and atmospheric CO₂. The glaciations occasioned migrations of hundreds of kilometres south, and tens of metres downshore, to appropriate temperatures and zones on the shore. Losses of species from Scotland's coastal fringe flora as a result of these assaults are poorly documented, and direct evidence from fossils is lacking for seaweeds; more certainly, the present native coastal fringe flora must have managed to survive the last glacial-interglacial cycle although presumably not in Scotland. This does not necessarily mean that the coastal fringe species can withstand the current anthropogenic greenhouse effect (global warming) in which CO₂ partial pressure started to increase in about 1800, with subsequent increases in temperature and sea level, since the upper limits of the excursions of these three environmental factors during the last glacial- interglacial cycle may soon be exceeded. Furthermore, the rate of increase of these factors may be greater than that found in the glacial-interglacial transitions. Coastal fringe vegetation may also be threatened by more local anthropogenic actions, e.g. physical modification of the habitat by coastal defences against sea level increase, inputs of chemical pollutants, and direct harvesting of native plants or introduction of exotics. It is clear that, when the perturbation is removed, the vegetation can be substantially restored at least under present environmental conditions. Scottish botanists, while not able unaided to influence the global threats, can and should take action to minimize local anthropogenic threats, and monitor, and respond flexibly to, the response of the vegetation to the global and local changes.     

Committee for the study of the Scottish Flora

Background: Damage to alpine plant communities is likely to occur when hikers and pack animals trample vegetation. Currently, there is limited research that quantifies and compares impacts from these activities.

Aims: A manipulative experimental protocol was used to assess damage to alpine meadows by pack animals and hikers in the Aconcagua Provincial Park, Andes, Argentina.

Methods: Vegetation height, overall cover, cover of dominant species and species richness were measured immediately after, and 2 weeks after different numbers of passes (0, 25, 100 and 300) by hikers or pack animals in an experiment, using a randomised block design.

Results: Pack animals had two to three times the impact of hiking on the meadows, with greater reductions in plant height, the cover of one of the dominant sedges and declines in overall vegetation cover after 300 passes. Impacts of pack animals were also apparent at lower levels of use than for hikers. These differences occurred despite the meadow community having relatively high resistance to trampling due to the traits of one of the dominant sedges (Carex gayana).

Conclusions: Pack animals caused more damage than hikers to the alpine meadow, but the scale of the difference in short-term impacts depends on the characteristics of the plant community, the amount of use and the vegetation parameters measured. Use of the meadows by hikers and pack animals should be minimised as these meadows are scarce, and have high conservation values.     

NHSnet in Scottish primary care: lessons for the future

ObjectiveTo evaluate the primary care communications initiative, which introduced NHSnet to primary care in Scotland.DesignSemi-structured telephone interviews, postal questionnaire.SettingAll 15 Scottish health boards, random sample of 1 in 3 of all Scottish general practices.ParticipantsInformation management and technology managers of health boards, 355 practice managers in the general practices.Results99% of Scottish general practices agreed to participate in initiative. Health boards varied significantly in project management styles (from minimal to total control), the nature of the networks they established (intranets or direct connections), costs to practices (from nothing to £125 per general practitioner per year), and training provided (from none to an extensive programme). In 56% of practices someone accessed NHSnet at least once a week. Practices varied considerably in amount of internet training received and staff groups targeted and in the intention to provide desktop access to NHSnet through a practice network.ConclusionThe initiative has successfully introduced a network that links Scottish general practices, health boards, and hospital trusts. However local variation in this “national” initiative may affect its use in primary care. Health authorities and general practices in England and Wales may wish to note these findings in order to avoid unhelpful variation.     

Losses and gains to the Scottish Flora

Summary

Several examples are discussed of plants which have been exterminated from or introduced to Scotland as a result of human activities, and an attempt is made to draw lessons from these case histories. Four rare or threatened Scottish plants, Homogyne alpina, Mertensia maritima, Primula scotica, and Pteridium aquilinum ssy. latiusculum are considered to illustrate future plant conservation imperatives. Threats to the Scottish flora of a more “institutional” nature are discussed, and it is suggested that these point to the need for botanical societies to consider a more “campaigning” role.     

Vegetation change at high elevation: scale dependence and interactive effects on Niwot Ridge

Background: High-elevation mountain systems may be particularly responsive to climate change.

Aims: Here we investigate how changes along elevation gradients in mountain systems can aid in predicting vegetation distributional changes in time, focusing on how changing climatic controls affect meso-scale transitions at the lower and upper boundaries of alpine vegetation (with forest and subnival zones, respectively) as well as micro-scale transitions among plant communities within the alpine belt. We focus on climate-related drivers, particularly in relation to climate change, but also consider how species interactions, dispersal and responses to disturbance may influence plant responses to these abiotic drivers.

Results: Empirical observations and experimental studies indicate that changing climatic controls influence both meso-scale transitions at the upper and lower boundaries of alpine vegetation and micro-scale transitions among plant communities within tundra. Micro-scale heterogeneity appears to buffer response in many cases, while interactions between climate and other changes may often accelerate change.

Conclusions: Interactions with microtopography and larger edaphic gradients have the capacity to both facilitate rapid changes and reinforce stability, and that these interactions will affect the responsiveness of vegetation to climate change at different spatial scales.     

Limited effect of hare grazing and short-term climatic variations on the most common alpine vegetation community in the Snowy Mountains,Australia

Background: In the alpine zone of the Snowy Mountains, grazing by mammals is limited. However, introduced European hare numbers have increased since the 1970s.

Aims: To estimate the density of hares and hence grazing pressure among years. To assess the response of biomass, vegetation height and composition to a cessation of hare grazing.

Methods: We used indices of hare abundance based on spotlighting and counts of hare pellets on a transect. The effect of hare grazing on tall alpine herbfield was assessed by using 15 paired exclosure and control quadrats for six years.

Results: The indices of hare abundance suggested densities similar to those in upland areas of Britain. Grazing did not affect the composition, cover of herbs or graminoids or, for 2010, vegetation height or biomass. Variation in vegetation and hare numbers among years was not correlated with climatic variables. Observations of selective grazing suggested that impacts on vegetation may be localised and restricted to certain species. Prior analyses of hare pellets indicated that hares might spread seed of native and exotic species.

Conclusions: Hares are having no general effect on tall alpine herbfield but may affect certain plant species via selective grazing or by spread of viable seed.