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The article discusses the highlights of the 50th Annual General Meeting of the British Ecological Society held at the Botany Lecture Room at the University of London in England on January 3, 1969. The minutes of the 49th Annual General Meeting were taken as read, approved and signed. The report of the Honorary Secretaries was presented for discussion of the members present.

The article discusses the highlights of the 37th Annual General Meeting of the British Ecological Society held in the University of Oxford in Oxford, England on January 5 to 7, 1956. A soirée was held at the university's Department of Botany at which exhibits illustrating the ecological work in progress at Oxford were shown. A series of coloured slides of New Zealand vegetation were shown by professor Gordon of New Zealand. Some of the topics of the papers read at the meeting, include field populations of Calliphorine flies.

Information about the autumn meeting of the British Ecological Society is presented. The meeting was held at the Department of Botany of the University of Manchester in England from September 28-29, 1951. Papers discussed at the meeting include problems in the ecology of the lejeuneaceae, geographical affinities of the bryophytes and habitat preferences of mosses.

1. An earlier paper related bird species richness to hedgerows and other field boundary attributes including adjacent land use. The study was over several years (winter and summer) at two sites, Huntingdon and Swavesey, in East Anglia UK. 2. The present paper deals with similar relationships, but the bird variables used are the abundance of individual species, of groups of species (all finches, all raptors, etc.) and of all birds, as well as Simpson's index of diversity. This required extensive modelling — 105 models for Huntingdon and 174 for Swavesey. 3. The results of all 279 models are presented in a condensed form, highlighting the importance of given field boundary attributes to particular species or groups of species. 4. Like bird species richness in the earlier paper, the abundance of many species was strongly influenced by the land use, and by the main vegetation variables (tree height and number, hedgerow length, height and width). Land use was important to a larger majority of species, the exceptions being carrion crow, pheasant, reed bunting and wren. 5. Verge width appeared important for small insectivores (blue tit) and was particularly important for seed eating birds, e.g. most finches and buntings, redlegged partridge in summer, and carrion crow and skylark in winter. 6. Ditch dimensions were associated with the abundance of some seed eaters (linnet, reed bunting and goldfinch) and insectivores (blackbird, great tit, skylark, song thrush and wren). Kestrel and the groups raptors, corvids, waders and aquatics were associated with large ditches. 7. Though the general management prescriptions to benefit the majority of farmland birds were found to be similar to those in the earlier paper, the detailed species specific modelling made it possible to examine the habitat requirements of particular species. 8. Ecological evaluation of the results from the two studies are presented in a form considered to be of value for practical management. Bird... [ABSTRACT FROM AUTHOR]

Information about several papers discussed at the Easter meeting of the British Ecological Society held in London, England from April 3-4, 1951 is presented. Topics include the ecology of Hydropsychideae, or Tricoptera, the localization of Cladocera in lakes and ponds and the relationship between the natural habitat preferences of a particular animal and the choice of alternative ones' in towns. A topic on nature conservation was also discussed.

The article discusses the highlights of the autumn meeting of the British Ecological Society held in the Department of Botany at Bedford College in London, England on September 19 and 20, 1955. Several papers dealing with various aspects of the ecology of Calluna vulgaris were presented on the 19th, including a paper on experimental work to determine the effect of grazing wether sheep on enclosed areas of Calluneta. A discussion of the effects of burning heather is provided.

The article reports on the highlights of the annual general meeting of the British Ecological Society that was held at the Department of Zoology of the Imperial College of Science and Technology in South Kensington, England on January 7-8, 1955. Exhibits have been featured during the event, including two actinometers for solar radiation, illustrations of the ecology of a rock pool and the breeding of Atlantic seals.

The article reports on the highlights of the Easter Meeting of the British Ecological Society that was held in London, England on April 2-3, 1954. A. R. Clapham, a professor and president of the British Ecological Society, commenced the morning session on April 2, 1954. Several research papers were presented during the meeting, including those from Dr. Eville Gorham, Professor W. H. Pearsall and J. Brereton. On behalf of the Honorary Treasurer, the auditors' account was discussed by E. D. Le Cren during the meeting.

Information about several papers discussed at the Easter Meeting of the British Ecological Society held in Burlington House in London, England on April 7-8, 1952 is presented. Topics include the impact of rabbit to the agriculture in West Wales discussed by Prof. A. N. Worden and Ms. Winifred M. Phillips, the physiology of plants and plant ecology. Furthermore, the meeting was headed by Dr. C. B. Williams, president of the society and was attended by nearly one hundred members.

This paper studies how anglers in northern England invoke models of equilibrium and 'the balance of nature' in making sense of the water environments where they regularly fish, and how they use these models as norms or ideals when designing environmental management, alongside an emphasis on natural agency and unpredictability. Like other publics, anglers are shown to be a heterogeneous group in how they think about nature and their 'lay ecologies' reflect the problematic way in which equilibrium is normalised in science and policy more generally, showing similarities with professional environmental managers. But anglers are unusual publics, because their lay ecologies are put to work in collectively managing water environments, through stocking, culling and habitat management. Thus anglers' environmental knowledge practices co-produce the environments in which they develop their lay ecologies, making their models of nature and equilibrium important both conceptually and materially. [ABSTRACT FROM AUTHOR]

Information about the Winter and Annual General Meeting of the British Ecological Society held at the Science Lecture Theatre of Goldsmith College in London, England on January 3-5, 1966 is presented. Various papers regarding ecology were discussed in the event. Also, exhibits were conducted which showcased ecological dynamics.

The article discusses the highlights of the spring meeting of the British Ecological Society held at the Departments of Zoology and Botany in the University of Durham in Durham, England on March 29 to 31, 1955. A general account of zoological work in progress at Moor House was given by professor J. B. Cragg. J. A. Svendsen discussed the ecological studies on the earthworms associated with sheep dung at Moor House. It offers an overview of the group of papers on the ecology of litter fauna and flora.

Information about the annual general meeting of the British Ecological Society is presented. The meeting was held at the Department of Botany of the University of Oxford in England on January 5, 1952. It focused on the reporting of the honorary secretaries on the activities of the past year, which include the minutes of the previous annual meeting, the summer meeting and autumn meeting.

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.

This article introduces the summaries of papers presented at the Spring Meeting of the Tropical Group of the British Ecological Society held at the University College in London, England, on April 24, 1969. The African papers concentrated mainly on conditions in freshwater swamps. The South American papers were more general. The summaries of the main contributions are grouped according to continent.

Woodland colonization on wetlands is considered to have a detrimental effect on their ecological value, even though detailed analysis of this process is lacking. This paper provides an evaluation of the ecological changes resulting from succession of poor fen (base-poor mire) to willow wet woodland on Goss Moor NNR in Cornwall, UK. Different ages of willow carr were associated with eight understorey communities. During willow colonization, in the ground flora, there was a progressive decrease in poor fen species and an associated increase in woodland species, which appeared to be related to an increase in canopy cover and therefore shade. The most diverse community was found to be the most recent willow and was dominated by poor fen species. The oldest willow was the second most diverse and was associated with a reduction in poor fen species and an increase in woodland species. Architectural features were used successfully to assess the general condition and structure of willow. Tree height and DBH were identified as useful parameters to accurately assess willow age in the field. The implications of active intervention to remove willow in order to conserve the full range of communities within the hydrosere are discussed. [ABSTRACT FROM AUTHOR]

The article presents a study about the theoretical approach to a study of chalk grassland in England. This paper focuses on the six parts that make up the studies recorded in the past. A brief review of the history in literature of British Chalk Grassland is presented showing the general framework of the previous studies. Different variables in soil formation is detailed and the concepts in vegetation analysis are discussed featuring a functional approach which is a valuable tool in the assessment of various factors affecting the ecosystem balance.

Information about the annual meeting of the British Ecological Society held on January 5-6, 1950, at the Department of Botany, University College in Leicester, Engalnd is presented. The meeting, which was attended by 60 members and guests, opened with ecological exhibits and a method demonstration. The general meeting started with a signing of the minutes of the last annual meeting, followed by the council's report, election of officers and members, and presentation of various studies.

The article provides information on the annual meeting of the British Ecological Society in the University Department of Botany held in Oxford, England from January 5-6, 1944. H. N. Southern gave an interesting lantern lecture upon the ecology of birds. Exhibits set out to illustrate various aspects of ecology were examined. The feasibility of employing echo-sounding to give an outline of the main algal beds is examined.

The article discusses the highlights of the 7th Annual Meeting of the British Ecological Society held at the Botanical Department of the University College in London, England on December 18, 1920. The Honorable Treasurer presented the financial statement and balance sheet to December 31, 1919. Papers presented during the event included one by T. G. B. Osborn, a professor at the University of Adelaide, on the vegetation of South Australia.

Information about several papers discussed at the annual meeting sponsored by the British Ecological Society on fostering the study of ecology that was held at the Botanical Theatre in London, England on December 15, 1917 is presented. Topics include the method of demonstrating accretion on sandy and muddy foreshores by a layer of colored sand. The meeting featured several British ecologists including Mr. Wilmott, Mr. Fagg, and physician Salisbury.

The article discusses the highlights of a meeting of the Tropical Group held in the rooms of the Linnean Society in London, England, on November 4, 1964. The meeting discussed the pattern in dry tropical vegetation. Papers presented are "Pattern in Acacia-Capparis Semi-Desert Scrub in the Sudan," by P. Greig-Smith, "Termites and their Influence on Vegetation in the Drier Areas of Africa," by W. V. Harris, and "Vegetation Arcs in Somalia," by C. A. H. Hodge.

Information on several papers discussed at the Easter meeting of the British Ecological Society on April 6, 1940 in London, England is presented. Topics include the factors that differentiate marsh, fen and bog. Papers on water relations of raised-bog and blanket-bog, connemara bogs and habitat selection in Corixid bugs were read. The symposium featured notable persons including H. Godwin, T. T. Macan and D. Lack.

The article illustrates the scientific problem of the conservation of the heaths in Dorset, England. It presents three main causes of the heaths extensive anthropogenic changes, including the increased agricultural development, need for grown home timber and the scarcity of suitable sites for new plantations, and southward trend of the British human population. It describes the changes in area of heathland habitat and its fragmentation. It also forecast the fate of the existing flora and fauna in the light of observations made on the adaptations to changes in land use. Conservation and ecological implications of the work were also discussed.

The article discusses the effects of an aquatic plant called macrophytes to the river conditions of England. It claims that the growth of the plant is not limited by lack of major nutrients in River Ivel, while its enrichment by sewage effluent discharge has no obvious effect. It adds that the growth of the plant in the river is primarily determined by the amount of available solar radiation. Moreover, it states that studies of oxygen balance determine the overall photosynthetic and respiratory effect of plants to the river.

The article focuses on the ecology and plant distribution pattern of the Forty Acre Wood,in Chippenham Fen. It mentions that the Wood gives the clearest evidence of the operation of drainage factors upon the fen. It describes the woody and herbaceous vegetation occurring in the three zones in the area and states that the relative tolerance of the different tree species to ill-drainage is indicated by the distribution of trees in the zones. The alterations in the woodland brought about by varying drainage periods is also discussed.

This article discusses highlights of the annual meeting of the British Ecological Society in Cambridge, England in January 1945. An exhibit of photographs and herbarium specimens illustrating ferns from the high mountain vegetation of Jamaica was set out by H. Hamshaw Thomas. Seedlings of Juniperus communis from seeds collected on the Fleam Dyke has been shown by T. G. Tutin. P. W. Richards exhibited a cultivated specimen of Bartramia pomiformis.

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 discusses the highlights of a meeting of the British Ecological Society in the Botany School in Cambridge, England on January 2 to 4, 1934. Members of the society were entertained at a soirée. V. J. Chapman showed graphs and tables on the effect of tidal inundation on the species and communities of the salt marshes of Scolt Head Island. Meanwhile, C. Diver showed distribution maps of snails and Crambidae on South Haven Peninsula.

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.

Information about the British Ecological Society's Tropical group meeting held at the Westfield College in London, England on November 2, 1965 is presented in which the topic for discussion was the temperature as a factor in tropical ecology. Also, the event gave emphasis on the main contributions in ecology which include, papers about river fauna and forests.

The article discusses the highlights of a Meeting of the British Ecological Society held at the University of Manchester in England on December 19 to 21, 1914. In his address, Society President A. G. Tansley discussed forest and prairie in the central U.S. Professor R. H. Yapp presented the results of his investigations on the salt marsh formation of the Dovey estuary, near Aberystwyth, Wales. Other lecturers include F. W. Oliver, Lilian Baker, and Reverend T. A. Jefferies.

1. Earlier studies have reported that field vole Microtus agrestis populations in Kielder Forest, UK, exhibit typical 3–4-year cyclical dynamics, and that the observed spatiotemporal patterns are consistent with a travelling wave in vole abundance moving along an axis south-west–north-east at approximately 19 km year–1. One property of this wave is that nearby populations fluctuate more synchronously than distant ones, with correlations falling lower than the average for the sampling area beyond approximately 13 km. 2. In this paper we present a series of models that investigate the possibility that both the observed degree of synchrony and the travelling wave can be explained as a simple consequence of linking a series of otherwise independently oscillating populations. Our ‘coupled oscillator’ models consider a series of populations, distributed either in a linear array or in a two-dimensional regular matrix. Local population fluctuations, each with a 3–4-year period, were generated using either a Ricker equation or a set of discrete-time Lotka–Volterra equations. Movement among populations was simulated either by a fixed proportion of each population moving locally to their nearest neighbour populations, or the same proportion being distributed via a continuous geometric function (more distant populations receiving less). 3. For a variety of different ways of generating cycles and a number of different movement rules, local exchange between oscillating populations tended to generate synchrony domains that extended over a large number of populations. When the rates of exchange between local populations were relatively low, then permanent travelling waves emerged, especially after an initial invasion phase. There was a non-linear relationship between the amount of dispersal and the domain of synchrony that this movement generated. Furthermore, the observed spatiotemporal patterns that emerged following an initial invasion phase were found to be highly dependent on the extreme distances reached by rare dispersers. 4. As populations of voles are predominantly distributed in grassland patches created by clear-cutting of forest stands, we estimated the mean patch diameter and mean interpatch distance using a geographical information system (GIS) of the forest. Our simplified models suggest that if as much as 5–10% of each vole population dispersed a mean of 178 m between clear-cuts per generation, then this would generate a synchrony domain and speed of wave in the region of 6–24 km (per year), which is reasonably consistent with the observed synchrony domain and speed. Much less dispersal would be capable of generating this scale of domain if some individuals occasionally moved beyond the nearest-neighbour patch. 5. While we still do not know what causes the local oscillations, our models question the need to invoke additional factors to explain large-scale synchrony and travelling waves beyond small-scale dispersal and local density-dependent feedback. Our work also suggests that the higher degrees of synchrony observed in Fennoscandian habitats compared with Kielder may be due in part to the relative ease of movement of voles in these former habitats. As our work confirms that the rates of exchange among local populations will have a strong influence on synchrony, then we anticipate that the spatiotemporal distribution of clear-cuts will also have an important influence on the dynamics of predators of voles. [ABSTRACT FROM AUTHOR]

The article highlights the issues that emerged during the 14th New Phytologist Symposium held at the Royal Society in London, England in January 2006. The symposium addressed the broad goal of ecological development. Ecological development aims to close the gap between mechanisms and ecology, and provide a genuinely integrated view of plant development in its real environmental context. Knowledge of genetic mechanisms may be essential in understanding the degree of correlation or independence of plant responses to different environmental factors.

1. Two published data sets of helminths of the wood mouse Apodemus sylvaticus (L.) were analysed to test the hypothesis that the structure of these component communities is influenced by interactions between species. A range of tests, with differing null models, was applied to tease out the importance of controlling for subgroupings (e.g. sex, age, site, year, season) within the data when searching for significant associations based on prevalence (co-occurrence, presence/absence) or abundance (quantitative associations) data. 2. Significant differences from null models were detected for associations based on prevalence, but when subgroup constraints were taken into consideration, most lost significance. Among three and 15 pair-wise associations possible in data sets 1 and 2, respectively, only that between Trichuris muris and Heligmosomoides polygyrus was not dependent on context, and that between H. polygyrus and Catenotaenia pusilla, while always positive, varied in magnitude among sites of capture. 3. Pair-wise comparisons of abundance revealed three significant associations, only one of which ( H. polygyrus with C. pusilla) still remained significant after controlling for quantified extrinsic and intrinsic factors . With increasing burdens of H. polygyrus, mice carried more of other helminth species and this relationship remained significant after controlling for confounding factors. 4. Overall, positive co-occurrences of pairs of helminths of A. sylvaticus were highly context dependent and quantitative associations were weak and not convincing. Therefore, interactions between parasites are unlikely to play a dominant role among the processes that structure the component community of helminths in wood mice, in selected study sites in the south of England. [ABSTRACT FROM AUTHOR]

Summary Aim Using a large database that has been created over the past 5 years with the RECORDER package, presence/absence data for 829 species of vascular plants in the 103 1-km2 squares that cover the city of Plymouth (pop. 243,373) have been analysed by two-way indicator species analysis (TWINSPAN) and canonical correspondence analysis (CCA) to establish the major species assemblages and to examine their spatial distribution across the city in relation to variation in land use. Location The City of Plymouth. Methods Nine groupings of squares emerged and their distribution was mapped across the city. Interpretation of those groups and their variation in relation to the land use ordination axes showed that TWINSPAN groups lying along the first axis of variation correlated floristic variation with the process of urban development and the historical evolution of urban structure. The second axis appeared to be related to particular remnant semi-natural habitats within the city that could be regarded as ‘hot-spots’ for survival of many plant species. Species were categorized into four types on the basis of their recency and mode of arrival in the city and by using the historical flora of Plymouth produced by T. R. Archer-Briggs in 1880. Variations in the sources of species in relation to the TWINSPAN classification groups were then examined. A second ordination was also computed; this time with geological, altitudinal and distance variables. TWINSPAN groups were then superimposed on the ordinations using polygons to assist with biogeographical interpretation. Results and conclusions The results of both the multivariate analyses and distribution of species by source are then discussed in the context of previous research into urban plant ecology, particularly in Central Europe. The problems of inferring process from pattern in this meso-scale study are reviewed and suggestions are made for further research into urban ecology and biogeography in the city. [ABSTRACT FROM AUTHOR]

Details are given of four interesting new palaeobotanical records from an Ipswichian (last) Interglacial site in the East Midlands of England. The taxa are considered in the context of the site, and a brief review is presented of their Tertiary and Pleistocene history and present ecology, with some discussion of the phytogeographical implications. [ABSTRACT FROM AUTHOR]

Describes the biology, numbers, growth and production of the indigenous trout, Salmo trutta in Cow Green Reservoir, upper Teesdale, following impoundment in 1970. Comparisons made with pre-impoundment results; Reservoir trout spawned in autumn in afferent streams; Entry of the trout into the reservoir from afferent streams.

Evaluates the use of two different survey techniques for providing an estimate of the size of the common seal population on Orkney, England. Aerial and boat surveys conducted; Number of seals found hauled-out on the survey made during the moult; Recommendation regarding future estimates of population size.

Records of aquatic Coleoptera were assembled for 384 :sites in north-east England and the sites were classified using two-way indicator species analysis (TWINSPAN) and ordinated using detrended correspondence analysis (DECORANA). Nine habitats were interpreted from the TWINSPAN end-groups but it was found that one habitat represented by few sites was not classified by TWINSPAN and had to be determined from the ordination plot and from the experience of the recorders. Ordination of the sites suggested that in the north-east of England the major environmental influences on the formation of assemblages of water beetle species appeared to be acidity and the amount of oxygen in the water. A measurement of typicalness, based on ordination plots, was calculated for each site with a view to its use as a criterion for the evaluation of sites for wildlife conservation purposes. [ABSTRACT FROM AUTHOR]

(1) In two areas of Bristol, one 5.5 km [²], the other 3.2 km [²] fox litter counts in two consecutive years were used to estimate the number of fox groups. There were 3.64 family groups/km [²] in the smaller. In parts of the larger area densities of 4-5 family groups/km [²] were recorded. (2) To obtain data on the distribution and relative densities of foxes throughout Bristol nearly 88,000 school children were asked to record fox sightings for a period of one month. Since the absolute fox densities were known for two areas the distribution of recorded sighting could then be used to estimate fox densities throughout the city. By this means it was calculated that there were 211 fox family groups I an area of 116 sq km, a mean density of 1.82 fox family groups/km[²]. (3) Fox distribution in the city was uneven, and fox density was not found to correlate with household density, housing type, age of housing stock, or an other obvious habitat feature. There was a negative correlation (P< 0.001) between the distribution of stray dogs and urban foxes. This was attributed of the fox population by stray dogs. It is suggested that disturbance may be particularly important in the breeding season; dogs were the second major cause of mortality in young fox cubs. (4) Based on post-mortem material, it was calculated that the ratio of breeding to non-breeding vixen was 1:0.35, and so the adult fox population consisted of 211 males, 211 breeding females and 74 barren females. Assuming that all fox family groups breed each year, with a mean birth litter size of 4.80 (calculated from placental scars), the annual cub production would be 1013. [ABSTRACT FROM AUTHOR]

The distribution of otters and factors affecting it were studied along 130 km of the River Teme and 213 km of its tributaries in western England and eastern Wales during 1977. Five or six resident territories were located, very much below the potential carrying capacity of the habitat. The areas supporting otters had relatively more bankside vegetation, a greater density of trees, and more potential lying-up sites and holts for which ash and sycamore trees appeared particularly important. Disturbance, notably by anglers, is probably significant where cover is sparse. A positive conservation policy, involving the reversal of current management procedures, is outlined. [ABSTRACT FROM AUTHOR]

(1) The vertical distribution of leaves was recorded using a point quadrat, at intervals throughout 1981 and 1982 from grazed chalk grasslands in Sussex and Wiltshire, the data were analysed to describe the overtopping relationships between leaves of different species. (2) In most cases there was a positive correlation between the relative height of rosette leaves of each species ('relative leaf position') and their relative abundance. (3) Despite the short turf of these chalk grasslands (< 10 cm excluding inflorescence stalks) there is pronounced vertical structure, the tallest species (often graminoids) tend to be the most abundant, and the shortest species (often dicotyledons) the least abundant. (4) It is suggested that relative abundance is partly determined by competition for light and that there is a steady-state relationship between species with taller and with shorter rosette leaves. The balance between species is determined by grazing with taller species favoured between grazing events and the shorter species at the time of grazing. (5) In grazed chalk grasslands in southern England the balance falls in favour of species with taller and widely spreading growth-forms because grazing intensity is low and there is often a long time between successive grazing periods. (6) The species with shorter growth-forms persist, and the species with taller growthforms do not come to ecological dominance, because of chrome, differential defoliation. [ABSTRACT FROM AUTHOR]

Analyzes the ecological history of Wicken Fen in Cambridgeshire, England. Vegetation types that predominated on the Fen in the seventeenth century; Decline in peat extraction after 1800; Decrease in the total area of sedge in the twentieth century; Subdivision of the Fen during the seventeenth and eighteenth centuries.

(1) Mean relative growth rates (RGR) were estimated for a series of cohorts of three-leaved ramets of Carex flacca cloned from a single genet taken from a grassland in N. Derbyshire. (2) The cohort with the most vigorous growth had a mean RGR 2.18 times that of the least vigorous cohort. (3) Mean RGR was normally distributed against the logarithms of mean initial fresh weight per ramet (P < 0.01). (4) The fitted distribution predicted that individuals with an initial weight equal to that of the sample mean would have a mean RGR 1.13 times that of the sample mean, at 2 S.D. away from mean initial weight, mean RGR would be reduced to 0.71 of that of the sample mean. (5) Existing information, when combined with the present data, indicated that the extreme variation in mean RGR between species grown under productive conditions was about ten-fold, whereas variation between populations, genets and ramets was perhaps two-fold. (6) The distributions of mean RGR within the four levels of organization are discussed and the probabilistic implications of these distributions are briefly explored. [ABSTRACT FROM AUTHOR]

Reports on the result of the exclusion of sheep from grasslands in England. Patterns of vegetation; Changes in structure of grasslands.

Part III. Studies the life cycles on ant-hills of ten plant species with marked patterns in relation to ant-hills in chalk grassland at Beacon Hill, Aston Rowant National Nature Reserve in Oxfordshire, England from 1969 to 1972. Factors affecting the population sizes of the plant species.

The article highlights a study which provides a contrast in that the grassland and tall herb communities, on the Carboniferous Limestone of Derbyshire, examined all occur on soils containing free calcium carbonate. It mentions that the changes in the nutrient status of the plant-soil system after fire have been studied by estimating losses in the smoke, deposition in the ash, retention of soluble nutrients in the soil and by monitoring the nutrient content of vegetation at intervals after a fire. It concludes that the effects of fire in respect of plant nutrition are unimportant in the ecology of these communities relative to damage caused to the plants and alterations in the physical environment.

This article presents a study which investigated the influence of physical and chemical conditions on the spatial and temporal distribution of the phytoplankton and of an epipelic algae community in Abbot's pond in England. The study noted a marked vertical stratification of phytoplankton species during thermally stratified conditions. It also found that the positions of various species is related to physical and chemical conditions in the water column and in some cases to motility. The effects of shelter on the limnology and algal biology of Abbot's pond are discussed, and the possible future development of the pond is outlined.