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The article outlines recommendations relating to the accurate use of the taxonomic aspects of ecological investigations, which are approved by the Council of the British Ecological Society. The Council hopes that the Flora and Edition which has been used in determining the taxonomic concepts and nomenclature followed in the paper should be stated by contributors to the "Journal of Ecology." The Council also encourages the preservation of material of all the taxonomic units, from each plant community described. Finally, the Council calls on contributors to state the herbarium or herbaria in which his specimens have been deposited.

The article reports developments on the success of the "Journal of Ecology," the official publication of the British Ecological Society in Great Britain. The Impact Factor of the "Journal of Ecology" has increased by about 26 percent between 2004 and 2005. Jian-Ming Deng has awarded the 2006 John L. Harper Young Investigator's Prize for his paper about the relationship of plant mass-density and moisture gradient that was published in the journal. Meran Owen has been appointed as managing editor for the journal.

Information about several papers discussed at the exhibits sponsored by the British Ecological Society is presented. Topics include the purpose of land use mapping first as a record on maps of the actual and existing land use, and the Human Settlement and land use in Snowdonia against the background of vegetation ecology in the area. The meeting featured several speakers including Dr Woodhead, Dr Reynoldson, and Mr Le Cren.

The article offers information on the scheme for abstracting publications on the British Empire Vegetation. The proposed plan is to invite authors of papers and books dealing with vegetation and ecology to send to the Secretary of the Committee abstracts of their publications. It is noted that the abstracts will be collected and edited by a number of collaborators, and will then be published by arrangement with the British Ecological Society in the form of supplements to "The Journal of Ecology."

Information about the annual general meeting of the British Ecological Society held at the University College in London on January 6-7, 1949 and its thirty-fourth annual meeting held at Bristol University in London on January 9, 1948 are presented. Various woods and rare plants in Great Britain were discussed in the 1949 event accompanied by exhibits of various photographs of species while the 1948 meeting was about hydrography and ecology.

The article discusses the study which assesses the evidence from British hepatics with discontinuous distribution outside the British Isles in relation to the history of the British flora. In this paper, British hepatics showing disjunction in their world distribution are classified in six groups including mediterranean element, disjunct-temperate element and the American element. It is concluded that the hepatics considered do not form a homogeneous group and their distribution patterns all appear to be explicable in terms of post-glacial climatic change without invoking in situ survival through glaciation.

The article focuses on the Committee Report released by the British Ecological Society regarding the relevance and implication of the paper "The classification of tropical woody vegetation types," by J. Burtt Davy. According to the authors, Davy's essay commendable work should be recognized, however, his work does not present appropriate knowledge regarding the concept and classification of tropical woody communities which only uses a mixed criteria and is not based on habitat. It also offers information on the proper approach on the classification of woody vegetation communities as well as the basic formation type and units of study.

The article presents a summary of several studies related to ecology. These include "The shingle beach as a plant habitat," by F. W. Oliver, "The pelophilous formation of the left bank of the Severn estuary," by J. H. Priestley, "On the brown seaweeds of the salt marsh," by Sarah M. Baker, and "Ecological terminology as applied to marine Algae," by N. M. Johnson. A paper on the eastern moorlands of Yorkshire, England is also presented, as well as the research paper on the ecology of Calluna vulgaris.

Information about several papers discussed during the two Summer Meetings of the British Ecological Society (BES) is presented. During the first meeting which happened on June 29, 1918, the main topic discussed was on the effect of rabbits to the vegetation and formation of soil. In the second meeting, which was held on August 1-6, 1918, topics discussed was mainly focusing on the characteristic of hill and valley vegetation in the hill region of northern Great Britain.

This account presents information on all aspects of the biology of Liparis loeselii (L.) Rich. (Fen Orchid) that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the Biological Flora of Britain and Ireland: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, and history and conservation.Liparis loeselii is a small terrestrial orchid that has a circumboreal distribution and is widespread in Europe and North America. Despite its wide distribution, the species is locally rare and has declined considerably in most of its range. In Britain, the species has a disjunct distribution and is now known to occur consistently at only six sites in eastern England and three in south Wales. It is absent from Ireland. Its most characteristic habitats in Britain are inland fens and coastal dune slacks, but outside Britain it can also be found in wet meadows, marshes, forested seep springs, at lake borders or on mats of floating peat.Populations of Liparis loeselii in dune slacks tend to be short‐lived, and can rapidly increase in size or decrease and disappear as environmental conditions change. The species does not tolerate high nutrient concentrations or low pH. It is susceptible to drought, which reduces seed germination, seedling recruitment and adult survival. Heavy predation by rabbits and rodents has been observed under drought conditions.Liparis loeselii reproduces both by sexual reproduction, and by vegetative propagation through the production of pseudobulbs. Although flowers are accessible to insects, entomophilous pollination is unusual, and most sexual reproduction is the result of selfing. Fruits ripen late in the growing season (mid‐October) and the dust‐like seeds are dispersed during winter by wind and water. Germination occurs during the following growing season and is supported by a wide variety of mycorrhizal fungi.Since the late 19th century Liparis loeselii has declined considerably in Britain and elsewhere in Europe, primarily due to habitat destruction and loss, natural succession, and habitat desiccation due to drainage. As a result, the species has been listed as endangered in the Bern Convention and the European Habitat Directive (92/43/EEC) and is the focus of intensive conservation efforts in many countries. Restoration of habitat by mowing, extensive grazing and peat removal, and the creation of new habitat by dune slack formation in dune systems and peat removal in fens may prolong population persistence and promote establishment of new populations. [ABSTRACT FROM AUTHOR]

The article announces the decision of the British Empire Vegetation Committee to discontinue the series of abstracts which have been published in the "Journal of Ecology" since 1928. The intent of the scheme when it started was that authors books and papers on ecology relating to the Overseas Empire should send abstracts of their work to the Committee. It is cited that authors of ecological publications in the Empire have not responded to the scheme and very few authors' abstracts have been received. It offers information on the other sides of the Committee's work.

Information about several proceedings discussed at the nineteenth General and tenth Annual Meeting and field meetings sponsored by the British Ecological Society on ecology and environmental science is presented. Topics include the water content of developing and mature foliage leaves, dwarf oakwoods, and examination of vegetation and mollusca of the chalk downs at Aldbury. The symposium featured several professors including R. H. Yapp, W. L. Boys-Smith, and B. M.Griffiths.

Analyzes the pollen from basal peat deposits at a range of sites in the South Pennine Islands in Great Britain. Radiocarbon dated pollen diagrams; Protracted period of peat initiation; Formation of peat in two upland regions where Mesolithic activity was present.

The article presents an analysis on the grassland vegetation of the Sheffield region in Great Britain. Details related to physical and historical aspects of the region and to other general features of Sheffield grassland vegetation are presented. Characteristics of the varying land types of grassland are outlined. Various grassland types include Magnesian Limestone grassland, Carboniferous Limestone grassland, and F. ovina-Agrostis tenuis grassland. The major caused of variation in grasslands are directly connected to geological formations.

The article focuses on the study of the chemical elements of rain in the peat area near the Moor House National Nature Reserve in Great Britain to determine its degree of ombrogeny. The study measured the nutrient elements brought rain in the peat area for years, and assessed the effects of birds, smoke, and other pollution. The results of the conducted research found six elements from the rain, including inorganic nitrogen, phosphorus, and magnesium. The results were also compared with independent measurements, and chemical inventories of peat bogs.

The article examines the effect of soil potassium and wind-blown sea-spray in a South Wales dune grassland. The study describes the first stage of an examination of a calcareous dune, located on the north shore of the Bristol Channel of Braunton Burrows, grassland at Kenfig Burrows, Glamorganshire. It aims to define the relationship between nitrogen, phosphorus and potassium cycling and that annual productivity may be established for several plant associations of sandy, nutrient deficient soils.

The article focuses on the study on seasonal variation of total quantities of the nutrients found in rainfall at five places in Great Britain. The study, which was initiated by the International Biological Programme, studied the nutrients found in rainwater, and its contribution in plant nutrients. The research was conducted within three years, where results found that nutrients in rainwater include nitrogen, phosphorus, and magnesium. It was concluded that the marked maritime influences was affected by the topography of the area.

The article presents evidence for intra-specific competition in field populations of triclads. It stresses thet sessile habit of these plants explains the more satisfactory demonstrations of competition by botanists. The article also notes that the species is widespread in Britain and lives under variable biological conditions. Breeding occurs over most of the year but there are two peaks, a larger one in early spring and another in later summer. It explains that triclad populations in this account illustrate intra-specific competition well through determining the special characteristics of animals and special conditions.

The article offers information about several conventions of the British Ecological Society in Great Britain. The symposium titled "The Water Relations of Plants," organized by the Society on April 5-8, 1961, was attended by 112 members and overseas visitors. The meeting of the Tropical Ecology Group of the Society on April 6, 1961 in the Department of Botany was attended by 55 members which was arranged by P. W. Richards. The 1961 Summer Meeting was centered on the Departments of Botany and Zoology which was participated by 35 members who joined in the excursions by several local members. Various topics are also mentioned on each of the events.

The article discusses the regeneration of ash tree Fraxinus excelsior in woods where Mercurialis Perennis is prevalent in the field layer in the lowland areas in Great Britain. It is averred that Fraxinus seedlings sprout freely among dense Mercurialis but find themselves in a light intensity far below their compensation point. The ultimate disappearance of Fraxinus is chiefly referable to damping-off although poor assimilation and harm by insects contribute. Fraxinus seedlings on the shadowed woodland floors demonstrate marked persistence but small growth. The seedlings react quickly to the increased light when gaps are made.

The article presents a study that examines the horizontal organization or vegetation pattern of three plant communities in Great Britain, the Hillock wood, Pennine bog and Blakeney marsh (Limonium). The vegetation pattern of the communities was assessed using a method that was based on the analysis of data from numerous quadrats. The quadrats were used to determine the basic units of the horizontal organization. Study shows that the communities were consist of several basic units, one of which occupied over 60% of the community area and formed a matrix within the area where the other basic units were distributed. Drawing from the analysis, the author suggests that concept of minimal area should be replaced by the concept of basic units for the latter is more quickly to compute.

The article discusses the evolution of modern plant ecology in Great Britain. According to the author, the foundations were laid earlier and the conceptions of plant formations were developed by famous phytogeographers as Humboldt and Grisebach in the first half of the century. Furthermore, its modern meaning was determined by the publication of Warming in 1895 on "Plantesamfund: Grundträk af den ökologiske Plantegeografi." It was translated into German and widely used in England and America which it played as an important part in stimulating fieldwork for both countries. In 1898, A. F. W. Schimper published "Pflanzengeographie auf physiologischer Grundlage," which focus on the types of vegetation throughout the world and discusses the climatic and edaphic factors.

The article offers information about the annual meeting of the British Ecological Society at the University College in London, England, on January 5-6, 1939. Professor Tansley explained how pressure of work had made him unable to prepare a speech, and how the Council had made arrangements for it to be read at a meeting at Easter. Resignation of Mrs. Hand was accepted and Elflyn Hughes was elected as a new member of the society.

The article focuses on the study on the use of chalk flora to interpret the calcicole habit in the lower Greensand in Surrey, Great Britain. The study was conducted on a small piece of grassland, known to be calcareous sand, where the soil was seen to be physically typical of that of the chalk. The study found that chalk was scattered, and mixed with the sand for agricultural purpose many years before. It was concluded that factors determining the calcicole habit in vast majority of chalk grassland species are chemical.

The article presents a report about the activities of the British Ecological Society for the year 1932. The article contains information regarding the meetings of the organization held at the University of Oxford and Teesdale in England supplemented with the minutes of such meetings. Details about the excursion event and transplant experiments conducted by the Society are given. It also mentions the periodicals "The Journal of Ecology" and "The Journal of Animal Ecology" and provides a discourse about its membership. The article ends with an announcement of the resignation of O. V. Darbishire, one of the founders of the society.

The article focuses on the distribution of Primula elatior in Great Britain. It is contended that Primula elatior, even though wide-spread in the continent, is confined to two districts in Great Britain, forming a single area within which the plant grows in abundance in all old woods, and in small numbers in boggy meadows beside streams. The two districts are separated by a gap that is about 15 to 20 miles wide, formed by the valley of the River Cam. The author notes that the distribution of the Oxlip species is overlooked in Great Britain because it was confused with the widespread hybrid between the Cowslip and the Primrose.

Copyright of Journal of Ecology is the property of Wiley-Blackwell 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.)

Information about several papers discussed at a meeting by the British Ecological Society on ecology is presented. Topics include general ecology in Great Britain, works on the Society's laboratory, and light penetration. The meeting featured several members of the Society including Dr. Pearsall, and Dr. Worthington.

The article discusses the highlights of the summer meeting of the British Ecological Society at the Laboratory of the Ministry of Agriculture and Fisheries, Lowestoff from May 22-24, 1931. A brief account of marine fishery research was made by Doctor E. S. Russell, director of the Society. Other presentations on marine fishery research are made, including one by R. E. Savage on Phaeocystis poucheti in relation to Herring Shoals.

The article presents summaries of several articles that deal with the vegetation of some areas in Great Britain. They are "Blakeney Point in 1914," by F. W. Oliver, "Hydrilla verticillata in Britain," by W. H. Pearsall, "Pilura globulifera in Glamorgan," by M. Y. Orr, "Stratiotes aloides near Criebb," by R. C. Davie and "The Ecology of Knockdow Estate, Argyllshire," by Augusta Lamont. Information on the journals wherein the articles are published is provided, as well as the number of pages of the articles.

Information about several papers discussed at the general meeting of the British Ecological Society which was held on April 12, 1913 in the Botanical Department, University College in Great Britain is presented. Topics include the brief historical summary of the work of the British Vegetation Committee from its inception in 1904, and the resolutions of the British Ecological Society.

1. This account presents information on all aspects of the biology of Orchis mascula (L.) L. (early purple orchid) relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characteristics, herbivores and disease, history and conservation. 2. Orchis mascula is a native herb of the British flora. It is mostly found in woodland, copses, grasslands and open pastures, mostly on neutral or base-rich soils. It can also occur in hedgerows, scrub, on roadsides and railway banks, in grikes on limestone pavement and on moist cliff ledges. It is absent from very acid or very wet sites. It tolerates a sparse to moderately dense canopy, but it does not flower in deep shade. 3. Orchis mascula is a non-bulbous geophyte with little or no capacity for vegetative spread. The main perennating organ is a tuber (strictly a rootstem tuber). In most years the tuber generates a rosette of expanded leaves, and, at the end of every year of the plant's life, the tuber is replaced by at least one new tuber. Dormancy, the failure of above-ground parts to appear in a growing season, and the subsequent reappearance of full-sized photosynthetic plants in subsequent seasons, has been observed, but does not last longer than 1 year. The species is long-lived: it takes at least 4 years from first appearance above-ground to achieve flowering for the first time. The maximum recorded lifetime after first appearance is 13 years. 4. Orchis mascula is not autogamous and pollinators are necessary for successful pollination and fruit set. Flowers are nectarless, and pollinated by deceit, mainly by bumblebees and solitary bees. Natural levels of fruit set are usually < 20%. Hand-pollination can increase fruit set to. [ABSTRACT FROM AUTHOR]

1. As urbanization accelerates, interest is growing in the traits of urban plants. We classified 822 UK vascular plants on the basis of their occurrence along an urban–rural gradient in 26 710 samples of vegetation from 2508 UK 1-km grid squares, including a wide range of rural habitats and Sheffield and Birmingham, two of the UK's largest cities. 2. Both alien and native species were classified with respect to mean proportion of urban land cover in the 1-km grid squares in which the species occurs ( urbanity), and absolute frequency in highly urban grid squares ( urban frequency). Bayesian regression models were then developed for both measures, with a wide range of plant traits as explanatory variables. 3. Results for aliens and natives and for both urban measures were remarkably similar: the single, coherent picture of ‘successful urban species’ that emerges from our analysis is of robust plants of relatively fertile, dry, unshaded, base-rich habitats. Only seed mass behaved very differently for natives and aliens; seed mass was related positively to success of urban natives, and negatively to success of urban aliens. Neither clonality, seed dispersal nor seed persistence in the soil were strongly linked to success in urban habitats. 4. Synthesis. Cities can provide opportunities for surprisingly rich floras, but the traits of species that can persist in cities are quite narrowly circumscribed. More generally, it is clear that analysis of traits reveals important patterns in floristic data that would be far from obvious from a purely floristic analysis. [ABSTRACT FROM AUTHOR]

1 We quantify the effects of spatial structure on individual, population and community biomass within a natural community of annuals for two years (1994 and 1996) in which competition operated differently. 2 Using field-parameterized neighbourhood models in which we had previously estimated the spatial scale and magnitude of competitive effects, we perform virtual experiments in which we manipulate spatial structure relative to that observed. We first remove segregation by randomly re-labelling all annual plants in a focal plant's neighbourhood and then give individuals of all species the same average number of neighbours by re-locating individuals within the overall pattern of annuals. 3 The natural spatial structure generally acted to promote species coexistence. In 1994, when the strength of individual-level competition within species was already greater than that between species, the natural spatial structure enhanced this effect for six out of seven species by increasing the relative frequency of intraspecific contacts. Average plant biomass increased by 0.24–38% when spatial locations were randomized. 4 In 1996, when a single competitive hierarchy operated, the natural spatial structure systematically benefited small-seeded, weakly competitive species while having weak negative effects on large-seeded, strong competitors. Randomizing spatial locations decreased the biomass of the species with the smallest seeds by 12% but increased the biomass of the species with the largest seeds by < 1%. This asymmetry increased dramatically when we used the model to increase the competitive advantage of large seeds artificially. Randomizing spatial locations decreased the biomass of the species with the smallest seeds by 37% but increased the biomass of the species with the largest seeds by only 2.7%. 5 Effects of spatial structure on total community biomass were always small (maximum 7%). This was because common species always have weak spatial structure, and they draw down the effect on the community as a whole. 6 Our analysis, for the first time, quantifies the magnitude and direction of the effects of spatial structure in a natural community, and supports the conclusions of theoretical models that spatial structure can have substantial impacts on component species and community dynamics. [ABSTRACT FROM AUTHOR]

1 Plant species differ in their capacity to influence soil organic matter, soil nutrient availability and the composition of soil microbial communities. Their influences on soil properties result in net positive or negative feedback effects, which influence plant performance and plant community composition. 2 For two grassland systems, one on a sandy soil in the Netherlands and one on a chalk soil in the United Kingdom, we investigated how individual plant species grown in monocultures changed abiotic and biotic soil conditions. Then, we determined feedback effects of these soils to plants of the same or different species. Feedback effects were analysed at the level of plant species and plant taxonomic groups (grasses vs. forbs). 3 In the sandy soils, plant species differed in their effects on soil chemical properties, in particular potassium levels, but PLFA (phospholipid fatty acid) signatures of the soil microbial community did not differ between plant species. The effects of soil chemical properties were even greater when grasses and forbs were compared, especially because potassium levels were lower in grass monocultures. 4 In the chalk soil, there were no effects of plant species on soil chemical properties, but PLFA profiles differed significantly between soils from different monocultures. PLFA profiles differed between species, rather than between grasses and forbs. 5 In the feedback experiment, all plant species in sandy soils grew less vigorously in soils conditioned by grasses than in soils conditioned by forbs. These effects correlated significantly with soil chemical properties. None of the seven plant species showed significant differences between performance in soil conditioned by the same vs. other plant species. 6 In the chalk soil, Sanguisorba minor and in particular Briza media performed best in soil collected from conspecifics, while Bromus erectus performed best in soil from heterospecifics. There was no distinctive pattern between soils collected from forb and grass monocultures, and plant performance could not be related to soil chemical properties or PLFA signatures. 7 Our study shows that mechanisms of plant–soil feedback can depend on plant species, plant taxonomic (or functional) groups and site-specific differences in abiotic and biotic soil properties. Understanding how plant species can influence their rhizosphere, and how other plant species respond to these changes, will greatly enhance our understanding of the functioning and stability of ecosystems. [ABSTRACT FROM AUTHOR]

1 The distribution patterns of 391 rare and scarce British plants (species recorded in 100 or fewer 10 × 10 km squares) were characterized by their distributional area (area of occupancy at 1-km scale: AOO1) and levels of aggregation (as reflected in fractal dimensions measured across two scales: D1−10 and D10−100). 2 Eighteen plant traits were tested for relationships to AOO, and to fractal dimension while controlling for AOO. These included both directly heritable traits (e.g. life-form) and emergent properties that are, at most, indirectly heritable (e.g. typical local density). The latter set included an index of net distributional change and an index of range dynamism. 3 Only two traits, habitat preference and local abundance, were significantly related to AOO1, but about half were associated with fractal dimension. 4 Relatively aggregated fine-scale distributions (high D1−10) were related to high local abundance, lack of specialized, long-distance dispersal mechanisms, habitat preference and an increasing range size with relatively few local extinctions (i.e. a positive index of change with low dynamism). 5 Relatively aggregated coarse-scale distributions (high D10−100) were related to the use of insect pollinators, obligate outcrossing, habitat preference and relatively stable ranges (low dynamism). 6 Multivariate analyses of subsets of conceptually related variables showed that few variables interacted to affect distributional variables. 7 A highly significant negative relationship between dynamism and fractal dimension appears to be driven primarily by high rates of local extinction, leading to relatively scattered, diffuse range structures. Furthermore, it suggests that recent population trends may be inferred from snapshots of contemporary distribution patterns. 8 The role and interpretation of phylogenetically informed analyses in studies such as this are debatable. However, we found similar relationships in both phylogenetically informed and conventional analyses for all variables except pollination vector (a strongly conserved trait). 9 The spatial pattern of plant species distributions is associated with a range of ecological traits, particularly those describing past changes in distribution. The analysis of distribution patterns therefore has the potential to inform future conservation effort. [ABSTRACT FROM AUTHOR]

The article focuses on hedera helix L. Three subspecies of Hedera helix L also called as ivy are recognized. Ivy is common throughout the British Isles, except for parts of northern Scotland, with recorded introductions to northern and eastern Scotland, and to Shetland. The subspecies are undoubtedly under-recorded but H. helix ssp. helix is widely distributed. H. helix ssp. hibernica has a predominantly western natural distribution, with extensive introductions elsewhere. Ivies occur from sea level to 615 m in Ireland, to 550 m in Wales and Scotland and to 480 m in England

The article reports on the salient features of "Festuca longifolia." Festuca longifolia occurs on sandy heaths and acid grasslands in sixteen 10-km squares in Great Britain and six in the Channel Isles. Festuca longifolia grows under a range of climatic conditions from the frost-free habitats of south Devon and the Channel Islands to the low rainfall, droughty conditions of the Brecklands. Long hours of sunshine characterize all habitats. Festuca longifolia is a species of acid heaths and maritime cliffs.

Focuses on Primula farinosa L., a kind of primrose that is part of the biological flora of Great Britain. Geographical and altitudinal distribution; Habitat; Communities; Response to biotic factors; Response to environment; Structure and physiology.

Discusses characteristics of Taxus baccata, an evergreen non-resinous gymnosperm tree, in Great Britain. Geographical and altitudinal distribution; Habitat; Response to biotic factors; Structure and physiology.

Presents information on the plant species Smyrnium olusatrum L. which is found in Great Britain. Geographical and altitudinal distribution; Habitat; Communities; Response to biotic factors; Response to environment; Structure and physiology; Phenology; Floral and seed characters; Herbivory and disease; History.

Summary 1 Runoff production in blanket peat catchments of the northern Pennine hills, UK was measured through monitoring and experimentation at the plot, hillslope and catchment scale. Water flow from soil pipes was measured in one of the study catchments and overland flow, throughflow and water table were measured in runoff plots; rainfall simulation and tension-infiltrometry provided information on infiltration characteristics of the peat. 2 Saturation-excess overland flow was found to dominate the flashy flow regime; acrotelm stormflow, subsurface pipeflow and macropore flow were also found to be important components of the ecohydrological system. 3 Surface cover, topography and preferential flowpaths were found to be important factors in controlling infiltration and runoff production. 4 Streamflow generation processes that are consistent with the acrotelm-catotelm model are shown to occur in blanket peat with and without Sphagnum cover, but in one of the catchments studied an estimated 10% of the discharge bypassed this route and discharged via pipes. 5 The spatial and temporal variation in hillslope-scale runoff production was demonstrated in the study catchments. This variability in runoff production will be important for hydroecological understanding in peatlands but is often neglected because of over-simplification of processes provided by the traditional two-dimensional acrotelm-catotelm model. [ABSTRACT FROM AUTHOR]

Focuses on the 'trientalis europaea l.' a herb from the primulaceae family in Great Britain. Description of the growing environment; Area of growth; Observation of trientalis growth in pine forest and clear field.

Summary 1On many peatlands, a patterned landscape is formed by clusters of open-water pools enclosed by the peat of surrounding terrestrial and semi-aquatic habitats. Processes governing development of pool complexes operate over long time-scales (decades to millennia) that preclude direct observation and necessitate inferential analysis. 2We used present-day scaling relationships and spatial patterns of pools to test multiple hypotheses for development and dynamics of a bog pool complex in the Flow Country of northern Scotland. The complex included 641 permanent pools, ranging in surface area from 2.3 to 1930 m2 . 3Allometric scaling relationships and spatial analysis showed that the shape and distribution of pools is size- (or age-) dependent. With increasing size, pools became deeper relative to their surroundings and more convoluted and elongated in shape. Pool orientation and bathymetry were related to direction of slope. Small pools were located on the periphery of a focus now occupied by the largest pools. Peat depth varied systematically across the complex, leading to changes in both direction and gradient of water flow. 4The evidence suggests that pools formed initially where water tended to pond, and subsequently spread outward as the flat plateau expanded. Pools have accumulated sediment more slowly than surrounding areas, and the continued initiation of new pools seems to depend on this spatial variation in rates of sediment accumulation. Our study provides both a fuller understanding of the development of one pool complex, and techniques for comparative analysis of others. [ABSTRACT FROM AUTHOR]

(1) Populations of the ruderal Lactuca serriola were surveyed near to its northern distribution limit and elsewhere in Britain. The characteristics and vegetation of filly-eight L. serriola sites were surveyed and the plant's performance was assessed by morphological measurements. (2) Lactuca serriola becomes rarer towards its northern limit and is everywhere restricted to surprisingly low altitudes. seldom occurring above 80 m. (3) Typically, the vegetation of L. serriola sites consists of weedy grasses. annual ruderals and competitive biennial or perennial ruderals. Vegetational variation between sites relates to differences in the relative importance of these types of plants. Lactuca serriola itself grows in open patches and shows little association with its cohabitants. Near to its limit, it seldom occurs where competitive ruderals are an important feature of the vegetation. (4) Morphological variation shows little relationship to geographical location. Large plants are seldom found where competitive ruderals are important. (5) The lack of any marked decline in the vigour of L. serriola towards its limit is inconsonant with beliefs generally held about the control of geographical distribution limits. The significance of the behaviour of this species at its limit is discussed. [ABSTRACT FROM AUTHOR]

(1) The annual ruderal Lactuca serriola, which is confined in Britain to the south-east. was introduced into experimental sites in the north-west (Cheshire) and the south-west (Devon and Cornwall) and its survival and performance at these sites was compared with that within its natural area of distribution. (2) Seeds sown early in the autumn germinated quickly whereas seeds sown later germinated sporadically until December, Germination was affected by soil type, rainfall arid temperature, but was unimpaired beyond its distribution limit. (3) Winter growth was laster in the warmer sites regardless of where they were located relative to its limit. In Cheshire, plants had slightly lower winter dry weights and relative growth rates than in Essex, but the fastest growth was recorded in the south-west. Differences in the pattern of growth between Essex and Cheshire were reflected in higher leaf weight ratios among the Cheshire plants. All these differences disappeared when rapid growth started in the spring. (4) Development towards flowering and fruiting was always laster within its distribution limit than beyond it, but vernalized plants beyond the limit always shed their seeds before the onset of winter. No differences in fecundity within and beyond its limit were detected. (5) in normal years vernalization was essential for the plant to complete its life-cycle, but in the exceptionally hot summer of 1976 some non vernalized plants produced seed within its limit, but none did so beyond it. (6) In controlled environments the rate of development towards flowering was strongly related to temperature. At mean temperatures above 20 °C development was only slightly hastened. whereas below 14 °C it was delayed considerably: between these temperatures the response was linear. (7) Plants regenerated from self-sown seeds and persisted for several generations in all the sites after the experiments were finished. (8) It is concluded that the responses to the climate observed in L. serriola beyond its limit are too small for the limit to he explained in terms of failure in the individual plant. It is suggested that the responses of individuals must he related to their secondary effects on populations and metapopulations if the distribution limit of L. serriola is to be understood. [ABSTRACT FROM AUTHOR]

(1) British populations of Galeobdolon luteum (Lamiastrum galeobdolon) are almost all of the tetraploid (4n = 36) subsp montanum. Populations of this taxon growing in different environments, with a very vaned range of plant associates, show marked differences m such features as stolon production, leaf width, chlorophyll content, and the extent of flowering and fruiting. (2) Investigations of clones collected in Shropshire show that many of these differences are environmentally induced, although some are genetic in origin. (3) In studies of phenotypic plasticity, plants of clonal and of seedling origin were grown in the open and beneath shade-screens in cold frames which at midday received approximately 70% (A), 27% (B) and 6% (C) of the light available to the open treatment (O). Growth analysis showed that specific leaf area (SLA), leaf area ratio and fresh weight dry weight ratio were always highest in the most heavily shaded treatment Within the light ranges investigated, chlorophyll contents per unit dry weight of leaf were directly related to degree of shading Galeobdolon grew much better under Treatment A (70% light = 30% shade) than Oxalis acetosella did in similar experiments Total leaf area and stolon length were highest in Treatment B (73% shade), in which maximum leaf width was greater than that in the less shaded treatments (A and O). By the end of the first season total mean dry weight of seedlings in Treatments A and B was considerably greater than that in Treatment O (full light) and much higher than that in Treatment C (94% shade). Plants in this very densely shaded treatment differed from the others in showing a considerable increase m dry weight during the winter Well established plants in all treatments except the deepest shade (C) flowered well. (4) Shade leaves of Galeobdolon have better developed funnel-cells (palisade cells tapering strongly towards the spongy mesophyll) than do sun leaves are much thinner and have lower stomatal frequency... [ABSTRACT FROM AUTHOR]

Investigates limestone heaths in Great Britain. Maintenance of calcicole-calcifuge mixtures; Vegetation types; Influence of burning and grazing; Effects of erosion from steep slopes on permeable and soft substrata.

(1) Analyses of three heavy metals (lead, zinc and copper) in surface peat layers, dated peat profiles and surface vegetation samples from fifteen. British sites are discussed m the context of the movement of heavy metals in the peat system and the present-day and historical patterns of heavy metal accumulation in humified, slow-growing blanket peat. (2) The concentrations of heavy metals in the surface peat samples provide a basts for the division of the fifteen sties into two groups—'low-background' and 'high-background' sites—reflecting the current urban/industrial status of the sites. Significant regressions were found of the concentrations of lead and copper in the surface peat layers on the log[sub e] population of the nearest big town to each site. (3) Dating schemes for five peat profiles were produced by pollen analysis. Generalized linear dating-plots were obtained by correlating individual pollen features with documentary evidence of tree-planting and agrarian or industrial activity. Estimated rates of net peat accumulation varied from 1 cm in 5.5 years to 1 cm in 40 years. (4) Recent rates of heavy metal deposition were calculated for six sites where the rate of peat accumulation had been estimated from pollen analytical/radiocarbon dating. The deposition rates derived from the peat analyses for lead and copper were similar to those obtained by other workers from conventional deposition gauges. The rates for zinc were very much lower than the published figures, suggesting considerable losses by leaching of this metal from the peat surface. (5) Variation in the concentrations of heavy metals was examined in three dated peat profiles The distribution of lead in a 'low-background' profile apparently reflects national trends in production and utilization of lead during the last seven or eight centuries, while well-marked peaks in the lead profiles at two 'highbackground' sites are shown to correspond well with the documented history of the... [ABSTRACT FROM AUTHOR]

(1) Long-term studies on the effects of burning and grazing of semi-natural blanket bog have been carried out at Moor House National Nature Reserve. The bog is shown to be extremely variable in its structure and composition (2) The major effects of removal of the normal number of sheep (1 sheep per 0.44 ha) were an increase m the cover of Calluna vulgaris and a decrease in that of Eriophorum vaginatum, with an increase in lichen growth. (3) After burning there was an intermediate period of E. vaginatum dominance followed by regrowth of Calluna to form an uneven-aged stand, either alone or in combination with Eriophorum vaginatum and Sphagnum spp. (4) The effects of short (10-yr) and long (20-yr) rotation burning were investigated Calluna regeneration from seed and by vegetative regrowth was greater in the short rotation plots, and Rubus chamaemorus was considerably more abundant when short rotation burning was combined with removal of grazing. Increased grazing pressure allowed Eriophorum vaginatum to gain dominance at the expense of the dwarf shrubs, and considerably reduced lichen cover. (5) The consequences of these results are discussed with reference to long-term management, and it is concluded that light grazing by sheep, without burning, is likely to be an acceptable management in the interests of conservation. [ABSTRACT FROM AUTHOR]