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Southern England (southern + england)
Selected AbstractsGEOLOGICAL MODEL EVALUATION THROUGH WELL TEST SIMULATION: A CASE STUDY FROM THE WYTCH FARM OILFIELD, SOUTHERN ENGLANDJOURNAL OF PETROLEUM GEOLOGY, Issue 1 2007S.Y. Zheng This paper presents an approach to the evaluation of reservoir models using transient pressure data. Braided fluvial sandstones exposed in cliffs in SW England were studied as the surface equivalent of the Triassic Sherwood Sandstone, a reservoir unit at the nearby Wytch Farm oilfield. Three reservoir models were built; each used a different modelling approach ranging in complexity from stochastic pixel-based modelling using commercially available software, to a spreadsheet random number generator. In order to test these models, numerical well test simulations were conducted using sector models extracted from the geological models constructed. The simulation results were then evaluated against the actual well test data in order to find the model which best represented the field geology. Two wells at Wytch Farm field were studied. The results suggested that for one of the sampled wells, the model built using the spreadsheet random number generator gave the best match to the well test data. In the well, the permeability from the test interpretation matched the geometric average permeability. This average is the "correct" upscaled permeability for a random system, and this was consistent with the random nature of the geological model. For the second well investigated, a more complex "channel object" model appeared to fit the dynamic data better. All the models were built with stationary properties. However, the well test data suggested that some parts of the field have different statistical properties and hence show non-stationarity. These differences would have to be built into the model representing the local geology. This study presents a workflow that is not yet considered standard in the oil industry, and the use of dynamic data to evaluate geological models requires further development. The study highlights the fact that the comparison or matching of results from reservoir models and well-test analyses is not always straightforward in that different models may match different wells. The study emphasises the need for integrated analyses of geological and engineering data. The methods and procedures presented are intended to form a feedback loop which can be used to evaluate the representivity of a geological model. [source] BRONZE AGE BARROWS ON THE HEATHLANDS OF SOUTHERN ENGLAND: CONSTRUCTION, FORMS AND INTERPRETATIONSOXFORD JOURNAL OF ARCHAEOLOGY, Issue 1 2010RICHARD BRADLEY Summary The Bronze Age barrows on the downs of southern England have been investigated and discussed for nearly 200 years, but much less attention has been paid to similar structures in the areas of heathland beyond the chalk and river gravels. They were built in a phase of expansion towards the end of the Early Bronze Age, and more were constructed during the Middle Bronze Age. They have a number of distinctive characteristics. This paper considers the interpretation of these monuments and their wider significance in relation to the pattern of settlement. It also discusses the origins of field systems in lowland England. [source] USING AND ABANDONING ROUNDHOUSES: A REINTERPRETATION OF THE EVIDENCE FROM LATE BRONZE AGE,EARLY IRON AGE SOUTHERN ENGLANDOXFORD JOURNAL OF ARCHAEOLOGY, Issue 2 2007LEO WEBLEY Summary. It has recently been demonstrated that a number of roundhouses of the early first millennium BC in southern England show a concentration of finds in the southern half of the building. It has thus been argued that this area was used for domestic activities such as food preparation, an idea which has formed the basis for discussion of later prehistoric ,cosmologies'. However, reconsideration of the evidence suggests that this finds patterning does not relate to the everyday use of the buildings, being more likely to derive from a particular set of house abandonment practices. Furthermore, evidence can be identified for the location of domestic activities within contemporary roundhouses that appears to contradict the established model. [source] Habitat influences on urban avian assemblagesIBIS, Issue 1 2009KARL L. EVANS Urbanization is increasing across the globe and there is growing interest in urban ecology and a recognition that developed areas may be important for conservation. We review the factors influencing urban avian assemblages, focusing on habitat type and anthropogenic resource provision, and analyse data from a common bird monitoring scheme to assess some of these issues. The review suggests that (1) local factors are more important than regional ones in determining the species richness of urban avian assemblages, raising the potential for the management of urban sites to deliver conservation; (2) habitat fragmentation frequently influences urban avian assemblages, with the effects of patch size being greater than those of isolation, and (3) urban bird assemblages appear to respond positively to increasing the structural complexity, species richness of woody vegetation and supplementary feeding, and negatively to human disturbance. Data from Britain's Breeding Bird Survey, combined with habitat data obtained from aerial photographs, were used to assess a number of these issues at the resolution of 1-km squares. Green-space constituted 45% of these squares, and domestic gardens contributed 50% of this green-space, though their contribution to large continuous patches of green-space was negligible. There was no significant positive correlation between the densities of individual species in urban areas and surrounding rural areas. Rural species richness declined with increasing latitude, but urban species richness was not correlated with latitude. This contrast contributes to slightly higher avian species richness in rural squares in Southern England than urban ones. Occupancy and abundance were strongly positively correlated in urban avian assemblages, and some indicator species of conservation concern occurred in few urban areas and at low densities. Such species will require conservation action to be precisely targeted within urban areas. Of the urban indicators of conservation concern, only the House Sparrow Passer domesticus and Common Starling Sturnus vulgaris were more abundant in urban than rural areas. Moreover, the densities of these two species were strongly and positively correlated, indicating that they may be limited by shared resources, such as nest-sites or supplementary food. There was little evidence that high densities of nest-predating corvids were associated with reduced densities of their prey species. Species richness and the densities of individual species frequently declined with an increasing number of buildings. Current trends for the densification of many British urban areas are thus likely to be detrimental for many bird species. [source] Near-optimum short-term fade prediction on satellite links at Ka and V-bandsINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 1 2008Andrew P. Chambers Abstract Several short-term predictors of rain attenuation are implemented and tested using data recorded from a satellite link in Southern England, and a comparison is made in terms of the root-mean-square error and the cumulative distribution of under-predictions. A hybrid of an autoregressive moving average and adaptive linear element predictor is created that makes use of Gauss,Newton and gradient direction coefficient updates and exhibits the best prediction error performance of all prediction methods in the majority of cases. Copyright © 2007 John Wiley & Sons, Ltd. [source] A New Species of Amphirhagatherium (Choeropotamidae, Artiodactyla, Mammalia) from the Late Eocene Headon Hill Formation of Southern England and Phylogeny of Endemic European ,anthracotherioids'PALAEONTOLOGY, Issue 5 2001Jerry J. Hooker A new species of artiodactyl, Amphirhagatheriumedwardsi sp. nov., is described from the Late Eocene (Priabonian) Headon Hill Formation of the Hampshire Basin, southern England. The Haplobunodontidae, in which Amphirhagatherium is usually placed, has recently been combined with the monotypic Choeropotamidae, both essentially European endemic families. New anatomical information is forthcoming from both the new species and recently published data on related species. A cladistic analysis of taxa included in the two families, the possible anthracotheriid Thaumastognathus and the enigmatic Tapirulus, was conducted to test the relationships implied by observed morphological similarities. The genus Anthracobunodon is shown to be paraphyletic and is here synonymized with Amphirhagatherium. Choeropotamus and Thaumastognathus are sister taxa nested with three species of Haplobunodon and Haplobunodon is paraphyletic and polyphyletic, but this clade is too weakly resolved internally for reliable taxonomic changes. LophiobunodonTapirulus are sister taxa nested with a fourth species of Haplobunodon. The synonymy of the Haplobunodontidae with the Choeropotamidae is upheld and close relationship of the family with the Anthracotheriidae is argued to be unlikely. Choeropotamids are inferred to have had mixed frugivorous and browsing herbivorous diets. They seem to have diversified in the northern parts of Europe, some terminal taxa having originated following southward dispersal. [source] Thermal shock and germination in North-West European Genisteae: implications for heathland management and invasive weed control using fireAPPLIED VEGETATION SCIENCE, Issue 3 2009M.E. Hanley Abstract Question: Is the stimulation of germination by thermal shock (resulting from the passage of fire) commonly observed for Mediterranean-climate Fabaceae also apparent for NW European Genisteae (Fabaceae) species? Location: Southern England and NW France. Methods: The germination of Cytisus scopiarius, Genista anglica, Ulex europaeus, Ulex gallii and Ulex minor was examined following exposure to a range of temperatures (50°C, 65°C, 80°C, 95°C and 110°C) applied to seeds for 5 min. A sixth Mediterranean-origin species (Spartium junceum) was also included since it is a common invasive in NW Europe and North America. Results: All five native NW European species displayed increased germination following thermal shock, even when seeds were heated to 110°C. However, there was some variation depending on provenance: in contrast to seeds collected from southern England, germination of French C. scopiarius seeds was unaffected by temperature. Spartium junceum germinated most at 95°C, but was the only species to show reduced germination when seeds were heated to 110°C. Conclusions: The NW European Genisteae appear to be pre-adapted to the high temperatures associated with fire; a response attributable to their evolutionary origins in the fire-prone ecosystems of the Mediterranean Basin. Consequently, projected increases in fire frequency linked to climate change may stimulate their regeneration in NW European heathlands, potentially altering the species composition of these ecosystems. Additionally, a clearer understanding of the interaction between thermal shock and germination may explain why fire has so frequently been ineffective in controlling invasive Genisteae populations worldwide. [source] The making of a minor saint in Drogo of Saint-Winnoc's Historia translationis s. LewinnaeEARLY MEDIEVAL EUROPE, Issue 4 2008David Defries In 1058, the Flemish abbey of Saint-Winnoc stole St Lewinna's relics from a minster in southern England. The community worked to establish her cult in Flanders. Although scholars have focused on the material gain Saint-Winnoc probably hoped the cult would bring, this article argues that the development of the abbey's communal identity figured more prominently in its motives. The community saw Lewinna primarily as a means to help bolster its bid for independence from its mother house. [source] Selection for discontinuous life-history traits along a continuous thermal gradient in the butterfly Aricia agestisECOLOGICAL ENTOMOLOGY, Issue 6 2005Steve Burke Abstract., 1.,Voltinism may be conceptualised as the product of development rate and the timing of diapause , two components that together translate gradual environmental variation, through periods of growth and development, into ,generational units'. This may result in very different selection pressures on diapause induction and development time in populations with different numbers of generations per year. 2.,Developmental data from univoltine and bivoltine populations of the butterfly Aricia agestis (Lepidoptera: Lycaenidae) in North Wales were used to examine larval development time and the timing of diapause, and their contribution towards voltinism in populations that occur at the same latitude and in geographic proximity to one another along a thermal gradient. 3.,The critical photoperiod for diapause induction in univoltines and bivoltines from the same latitude differed by more than 1.5 h. 4.,Development time also differed significantly between these populations, in line with predictions that bivoltines would need to exhibit shorter development times in order to achieve two complete generations per year. Shorter development times for bivoltines result in lower pupal weights, suggesting a trade-off exists between generation number and body size that may dictate the position of the transition zone between the two life-history strategies. Analysis of development times in a third population, from southern England, with greater thermal availability than those from North Wales, further supports this hypothesised trade-off. 5.,To achieve the conversion of a continuous thermal gradient into the binary biological response from univoltism to bivoltism, bivoltines speed up development, reduce adult body size and shift their diapause induction response. [source] High-altitude migration of the diamondback moth Plutella xylostella to the U.K.: a study using radar, aerial netting, and ground trappingECOLOGICAL ENTOMOLOGY, Issue 6 2002Jason W. Chapman Abstract 1. The high-altitude wind-borne migration of the diamondback moth Plutella xylostella in the U.K. in 2000 was investigated (a) by direct monitoring of insect flight by vertical-looking radar and by aerial netting, and (b) through evidence of temporal variation in P. xylostella abundance deduced from a network of light traps. 2. Migrating P. xylostella were identified by a unique combination of size and shape data derived from the continuously operating vertical-looking radar. 3. Radar-detected migratory overflights correlated significantly with associated peaks in abundance of P. xylostella estimated by catches in a U.K.-wide light trap network; however the correlation was stronger when light trap catches were lagged by 1 day. 4. The first notable catches of P. xylostella in the U.K. occurred in early May, and were accompanied by migrations over the radar from the east. 5. Radar data and back-tracking indicated that a major wind-borne migration of P. xylostella from The Netherlands to southern England took place in early May, and that this was responsible for the establishment of the U.K. population. 6. The origin of early-season P. xylostella occurring in Britain is discussed. [source] Changes in environmental tobacco smoke (ETS) exposure over a 20-year period: cross-sectional and longitudinal analysesADDICTION, Issue 3 2009Barbara J. Jefferis ABSTRACT Aims To examine long-term changes in environmental tobacco smoke (ETS) exposure in British men between 1978 and 2000, using serum cotinine. Design Prospective cohort: British Regional Heart Study. Setting General practices in 24 towns in England, Wales and Scotland. Participants Non-smoking men: 2125 studied at baseline [questionnaire (Q1): 1978,80, aged 40,59 years], 3046 studied 20 years later (Q20: 1998,2000, aged 60,79 years) and 1208 studied at both times. Non-smokers were men reporting no current smoking with cotinine < 15 ng/ml at Q1 and/or Q20. Measurements Serum cotinine to assess ETS exposure. Findings In cross-sectional analysis, geometric mean cotinine level declined from 1.36 ng/ml [95% confidence interval (CI): 1.31, 1.42] at Q1 to 0.19 ng/ml (95% CI: 0.18, 0.19) at Q20. The prevalence of cotinine levels , 0.7 ng/ml [associated with low coronary heart disease (CHD) risk] rose from 27.1% at Q1 to 83.3% at Q20. Manual social class and northern region of residence were associated with higher mean cotinine levels both at Q1 and Q20; older age was associated with lower cotinine level at Q20 only. Among 1208 persistent non-smokers, cotinine fell by 1.47 ng/ml (95% CI: 1.37, 1.57), 86% decline. Absolute falls in cotinine were greater in manual occupational groups, in the Midlands and Scotland compared to southern England, although percentage decline was very similar across groups. Conclusions A marked decline in ETS exposure occurred in Britain between 1978 and 2000, which is likely to have reduced ETS-related disease risks appreciably before the introduction of legislation banning smoking in public places. [source] The effects of stream canopy management on macroinvertebrate communities and juvenile salmonid production in a chalk streamFISHERIES MANAGEMENT & ECOLOGY, Issue 2 2009W. D. RILEY Abstract, The effects of changes in shading (through riparian canopy removal and re-growth) on juvenile salmon, Salmo salar L., trout, Salmo trutta L., and grayling, Thymallus thymallus (L.) populations, and macroinvertebrate biomass and species composition in a chalk stream in southern England were examined. Low levels of in-stream weed growth, because of shading by closed tree canopy, diminished macroinvertebrate production and diversity. 0+ salmon and trout had lower densities under closed canopy, relative to adjacent open sites with substantial weed cover, where fish were also found to be larger. Canopy removal positively affected the growth of aquatic macrophytes and the availability of potential prey for juvenile salmonids. The findings have implications for the management of chalk streams, in particular, that riparian tree canopy should be managed to prevent complete closure, and excessive cutting of weed should be avoided where salmon production is below sustainable levels. [source] Effects of mute swan grazing on a keystone macrophyteFRESHWATER BIOLOGY, Issue 12 2007MATTHEW T. O'HARE Summary 1. This study describes the early summer foraging behaviour of mute swans (Cygnus olor) on the River Frome, a highly productive chalk stream in southern England in which Ranunculus penicillatus pseudofluitans is the dominant macrophyte. 2. A daily maximum of 41 ± 2.5 swans were present along the 1.1 km study reach during the study period (late May to the end of June). The river was the primary feeding habitat. Feeding activity on the river at dawn and dusk was much lower than during daylight, but we cannot rule out the possibility that swans fed during the hours of darkness. 3. The effects of herbivory on R. pseudofluitans biomass and morphology were quantified. Biomass was lower in grazed areas and swans grazed selectively on leaves in preference to stems. A lower proportion of stems from grazed areas possessed intact stem apices and flowering of the plant was reduced in grazed areas. 4. A model, based on the swans' daily consumption, was used to predict the grazing pressure of swans on R. pseudofluitans. The model accurately predicted the number of bird days supported by the study site, only if grazing was assumed to severely reduce R. pseudofluitans growth. The proportion of the initial R. pseudofluitans biomass consumed by a fixed number of swans was predicted to be greater when the habitat area was smaller, initial R. pseudofluitans biomass was lower and R. pseudofluitans was of lower food value. 5. We concluded that the flux of N and P through the study reach was largely unaffected by swan activity. The quality of R. pseudofluitans mesohabitat (the plant as habitat for invertebrates and fish) was significantly reduced by grazing which also indirectly contributed to reduced roughness (Manning's n) and by inference water depth. Wetted habitat area for fish and invertebrates would also be lowered over the summer period as a consequence of the reduction in water depth. It was estimated that, while grazing, an individual swan may eat the same mass of invertebrates per day as a 300-g trout. 6. There is a need to manage the conflict between mute swans and the keystone macrophyte, R. pseudofluitans, in chalk streams, and the modelling approach used here offers a potentially useful tool for this purpose. [source] Herbivory in an acid streamFRESHWATER BIOLOGY, Issue 4 2000Mark E. Ledger Summary 1Spatial and temporal variation in the distribution and feeding of non-predatory macroinvertebrates was investigated in a first-order, acid stream in the Ashdown Forest, southern England. 2Stonefly (Nemouridae) and chironomid (Orthocladiinae) larvae were abundant on the upper surfaces of mineral substrata of three sizes (small stones, large stones, bedrock). The density of larvae in each taxonomic group did not vary among substrata of different sizes, although strong seasonal variation existed. 3Nemourids and chironomids (H. marcidus) collected from the upper surfaces of substrata exhibited generalist feeding habits, consuming algae (diatoms, coccoid and filamentous green algae), detritus (biofilm matrix material and fine particulate organic matter (FPOM)) and inorganic debris. 4There was spatial variation in the gut contents of nemourids. The proportion of algae in the guts of larvae often increased with the size of the substratum from which they were collected. Strong temporal variation in the composition of the diet also existed. Nemourids ingested a large quantity of attached algae and biofilm matrix from the biofilm in spring and winter, but consumed loose FPOM and associated microflora in summer and autumn. 5We conclude that, in this acid stream, the trophic linkage between algae and grazers is maintained by ,detritivorous' stonefly and chironomid species. The relationship between the feeding habits of these larvae and other life-history attributes, such as mouthpart morphology and mobility, is discussed. [source] The response of manured forage maize to starter phosphorus fertilizer on chalkland soils in southern EnglandGRASS & FORAGE SCIENCE, Issue 2 2000Withers The impact of various starter phosphorus (P) fertilizers on the growth, nutrient uptake and dry-matter (DM) yield of forage maize (Zea mais) continuously cropped on the same area and receiving annual, pre-sowing, broadcast dressings of liquid and semi-solid dairy manures was investigated in two replicated plot experiments and in whole-field comparisons in the UK. In Experiment 1 on a shallow calcareous soil (27 mg l,1 Olsen-extractable P) in 1996, placement of starter P fertilizer (17 or 32 kg ha,1) did not benefit crop growth or significantly (P > 0·05) increase DM yield at harvest. However, in Experiment 2 on a deeper non-calcareous soil (41 mg l,1 Olsen-extractable P) in 1997, placement of starter P fertilizer (19 or 41 kg P ha,1), either applied alone or in combination with starter N fertilizer (10 or 25 kg N ha,1), significantly increased early crop growth (P < 0·01) and DM yield at harvest by 1·3 t ha,1 (P < 0·05) compared with a control without starter N or P fertilizer. Placement of starter N fertilizer alone did not benefit early crop growth, but gave similar yields as P, or N and P, fertilizer treatments at harvest. Large treatment differences in N and P uptake by mid-August had disappeared by harvest. In field comparisons over the 4-year period 1994,97, the addition of starter P fertilizer increased field cumulative surplus P by over 70%, but without significantly (P > 0·05) increasing DM yield, or nutrient (N and P) uptake, compared with fields that did not receive starter P fertilizer. The results emphasized the extremely low efficiency with which starter P fertilizers are utilized by forage maize and the need to budget manure and fertilizer P inputs more precisely in order to avoid excessive soil P accumulation and the consequent increased risk of P transfer to water causing eutrophication. [source] Characteristics of woods used recently and historically by Lesser Spotted Woodpeckers Dendrocopos minor in EnglandIBIS, Issue 3 2010ELISABETH C. CHARMAN Lesser Spotted Woodpecker Dendrocopos minor numbers have declined greatly in England since the early 1980s for reasons that are not yet fully understood. It has been suggested that the species' decline may be linked to the increase in Great Spotted Woodpeckers Dendrocopos major, changes in woodland habitat quality (such as deadwood abundance) and landscape-scale changes in tree abundance. We tested some of these hypotheses by comparing the characteristics of woods in southern England where the species is still relatively numerous with those of woods used in the 1980s before the major decline. In each time period, habitat, predator and landscape information from woods known to be occupied by Lesser Spotted Woodpeckers was compared with those found to be unoccupied during surveys. Before the main period of decline, Lesser Spotted Woodpeckers used oak-dominated, mature, open woods with a large amount of standing deadwood. Habitat use assessed from recent data was very similar, the species being present in mature, open, oak-dominated woodlands. There was a strong relationship between wood use probability and the extent of woodland within a 3-km radius, suggesting selection for more heavily wooded landscapes. In recent surveys, there was no difference in deadwood abundance or potential predator densities between occupied and unoccupied woods. Habitat management should focus on creating and maintaining networks of connected woodlands in areas of mature, open woods. Finer-scale habitat selection by Lesser Spotted Woodpecker within woodlands should be assessed to aid development of beneficial management actions. [source] Survival rates, causes of failure and productivity of Skylark Alauda arvensis nests on lowland farmlandIBIS, Issue 4 2002P. F. Donald This paper analyses data from 995 Skylark Alauda arvensis nests found on lowland farms in southern England from 1996 to 1998. The majority of recorded nest failures were caused by predation except in agricultural grass, where trampling and agricultural operations were equally important. Nest survival rates varied between crop types, nests in cereals being around twice as likely to succeed as nests in grass or set-aside. In cereals, nest survival rates increased with increasing distance from the nearest tramline and declined over the course of the breeding season. Predator control also had a significant independent effect on nest survival rates. On one farm where many other factors were held constant, a highly significant increase in nest survival rates from 12.3% to 40.7% coincided with the introduction of intensive predator control, which also appeared to bring forward mean laying dates. Most environmental factors explaining significant variation in nest survival rates did so only at the chick stage. The mean number of chicks produced per nesting attempt was 1.26 in cereals, 0.78 in set-aside and 0.63 in grass, the differences being due primarily to variation in nest survival rates. Low densities of Skylark territories in cereal crops are not therefore the consequence of low breeding success at the scale of the individual nest and probably reflect limitations on the number of attempts made in a season. Measures taken to improve the attractiveness of cereal crops as a nesting habitat for Skylarks, and beneficial changes in grassland management, are likely to increase overall productivity. [source] Movement characteristics of the Scarce Blue-tailed Damselfly, Ischnura pumilioINSECT CONSERVATION AND DIVERSITY, Issue 1 2010KATHERINE A. ALLEN Abstract., 1. The Scarce Blue-tailed Damselfly, Ischnura pumilio, is threatened in the UK and exists in small, transient colonies. Consequently, little is known about its dispersal characteristics. This study investigates movement in two contrasting habitats with the aim of informing conservation management on a landscape scale. 2. Mark-release-recapture studies were performed at an established colony in the New Forest and a smaller population in the Red River valley in southern England. A total of 2304 individuals was marked. 3. Ischnura pumilio was found to be exceptionally sedentary. Mean gross lifetime movement was 56 m and 43% of individuals moved <50 m in their lifetime. Movements over 150 m were very rare. Maximum lifetime movement was 1165 m. As such, I. pumilio is the most sedentary odonate studied in the UK to date. 4. Movement was inversely density dependent, which has important conservation implications if individuals attempt to emigrate from small populations because of low density. The presence of parasitic mites (Hydryphantes sp.) significantly increased movement distance. 5. Ischnura pumilio had a low dispersal probability compared to other damselflies. As the smallest British odonate, this is in keeping with the relationship between size and dispersal found across taxa. 6. Ischnura pumilio has been regarded as a ,wandering opportunist' due to its tendency to appear in locations far from known sites. However, this study suggests that long range movement rarely occurs from prime habitat that is maintained in an early successional stage. This has implications for the conservation of the species in the UK. [source] Uncertainties in early Central England temperaturesINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 8 2010David E. Parker Abstract Uncertainties in historical climate records constrain our understanding of natural variability of climate, but estimation of these uncertainties enables us to place recent climate events and extremes into a realistic historical perspective. Uncertainties in Central England temperature (CET) since 1878 have already been estimated; here we estimate uncertainties back to the start of the record in 1659, using Manley's publications and more recently developed techniques for estimating spatial sampling errors. Estimated monthly standard errors are of the order of 0.5 °C up to the 1720s, but 0.3 °C subsequently when more observing sites were used. Corresponding annual standard errors are up to nearly 0.4 °C in the earliest years but around 0.15 °C after the 1720s. Daily standard errors from 1772, when the daily series begins, up to 1877 are of the order of 1 °C because only a single site was used at any one time. Inter-diurnal variability in the daily CET record appears greater before 1878 than subsequently, partly because the sites were in the Midlands or southern England where day-to-day temperature variability exceeds that in the Lancashire part of Manley's CET. Copyright © 2009 Royal Meteorological Society [source] Episodes of alpine heavy precipitation with an overlying elongated stratospheric intrusion: a climatologyINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 9 2006Olivia Martius Abstract This study discusses the role of stratospheric intrusions (determined as potential vorticity (PV) streamers) as upper-level instigators of heavy precipitation along the Swiss Alpine south side (AS) on a climatological timescale. A climatology of streamers is used compiled on the basis of the ECMWF 40-year re-analysis data set (ERA-40). Days of extreme and heavy precipitation along the Swiss AS are determined from an existing observational Alpine precipitation climatology. For these days, the presence of streamers over western Europe as well as their location and orientation is recorded. On 73% of the extreme precipitation days, a streamer is situated over western Europe. The mean spatial frequency distribution of the streamers on the extreme precipitation days exhibits a structure that resembles in its form and location the ,archetypal heavy precipitation streamer' known from case studies. The frequency maximum is situated over southern England and the west coast of France. The same analysis is applied to three sub-domains (Valais, Grisons, Ticino) along the Swiss AS. Significant differences in the location and the orientation of the streamers for the sub-domains are found. The majority of streamers associated with heavy rain in the western-most sub-domain (Valais) are oriented in a cyclonically-sheared fashion, while for the Ticino the streamers are more anti-cyclonically orientated. Differences for events of increasing severity are analysed by comparing the form, location, amplitude (PV), and persistence of the streamers on extreme and heavy precipitation days. The precipitation distribution is shifted to higher intensities for more persistent streamers. There is no detectable difference found in the form parameters, but the southerly moisture flux into the domain is significantly larger during extreme precipitation days than during heavy precipitation days. Likewise, the seasonal variation in the percentage of streamer-related heavy precipitation, which is highest in autumn (85%), can be related to the seasonal variation of southerly moisture fluxes. Copyright © 2006 Royal Meteorological Society. [source] Host community attitudes toward tourism and cultural tourism development: the case of the Lewes District, southern EnglandINTERNATIONAL JOURNAL OF TOURISM RESEARCH, Issue 1 2006Brent W. Ritchie Abstract Increasingly research is being conducted on host community attitudes toward tourism. However, few studies have been conducted at a regional level and none have examined the attitudes of the host community towards both tourism and cultural tourism development. This paper outlines a study conducted in the Lewes District of southern England and notes that although residents are generally supportive of tourism development and cultural tourism development, there are differences in opinion concerning the perceived economic and social benefits. In particular, levels of income and proximity to the tourist centre were major influencing factors. Conclusions and recommendations are made concerning the need for tourism planners to distribute the benefits more widely and to engage residents from different socio-economic groups and localities in tourism planning and development activities. Copyright © 2006 John Wiley & Sons, Ltd. [source] Long-term enhancement of agricultural production by restoration of biodiversityJOURNAL OF APPLIED ECOLOGY, Issue 1 2007JAMES M. BULLOCK Summary 1Experimental manipulations have shown positive impacts of increased species richness on ecosystem productivity, but there remain some questions about this relationship. First, most studies last < 4 years, which raises issues about whether diversity,productivity relationships are maintained in mature communities. Secondly, the conservation relevance of many studies is debatable. We addressed both issues using long-term experimental studies of the agriculturally relevant hay yield of recreated species-rich grasslands. 2Grasslands were recreated within replicated experiments in ex-arable fields at two sites in southern England by using either species-poor or species-rich seed mixtures. The species-poor mixture comprised seven grasses as recommended for grassland creation in English agri-environment schemes. The species-rich mixture comprised 11 grasses and 28 forbs and was designed to recreate a typical southern English hay meadow. 3After 8 years the plots sown with species-rich mixtures resembled target diverse community types. The plots sown with species-poor mixtures had been colonized by a number of forbs but had lower numbers of grasses, legumes and other forbs than the species-rich plots. Increased hay yield of the species-rich plots in the first years of the experiments have been described in an earlier paper, and these differences were maintained after 8 years. 4In the eighth year the species-rich plots had an average 43% higher hay yield than the species-poor plots. Regression analysis showed that the variation in hay yield was related to differences in the number of non-leguminous forbs and showed no relation to grass or legume numbers. This suggests increased hay yield is an effect of the greater range of life forms exhibited by forbs rather than a simple fertilizing effect of legumes. 5The nitrogen content and phosphorus content of the hay showed complex treatment effects over time. However, the nutritional value of the hay was above the minimum requirements for livestock. 6Synthesis and applications. The aims of conservationists and farmers can often be in conflict. This study has shown that the recreation of diverse grasslands of conservation value can have a positive impact on hay yield, which benefits the farm business, and this is repeated across differing sites. Because the effect is maintained over time, farm income will be increased in the long term. [source] The resilience of calcareous and mesotrophic grasslands following disturbanceJOURNAL OF APPLIED ECOLOGY, Issue 3 2005RACHEL A. HIRST Summary 1Understanding habitat disturbance and recovery is vital for successful conservation management and restoration, particularly of subseral communities with high nature conservation interest and sites subject to unavoidable disturbance pressures, such as that arising from access and recreational activities. 2Grassland resilience was investigated on the Salisbury Plain Training Area (SPTA) in southern England, the largest of the UK military training areas. SPTA contains the greatest expanse of unimproved chalk grassland in north-west Europe, a habitat of particular nature conservation interest. 3Historical aerial photographs were used to identify 82 calcareous and mesotrophic grassland sites disturbed over a 50-year time period. Vegetation, soils and seed bank data were collected from each old disturbance site. Revegetation time periods following disturbance were compared, and habitat resilience following disturbance investigated using the succession of surface vegetation along the chronosequence, the combined changes of vegetation and soil chemistry, and finally vegetation and seed bank composition. 4The sampled calcareous grasslands were less resilient following disturbance than the mesotrophic grasslands, with slower colonization of bare ground and target species re-assembly. The mesotrophic grasslands typically took between 30 and 40 years to re-establish following disturbance, whereas calcareous grasslands took at least 50 years. 5Even after such long time periods, there remained subtle but significant differences between the vegetation composition of the disturbed and undisturbed swards. Perennial forb species, particularly hemicryptophytes, persisted at higher frequencies in swards disturbed 50 years ago than in undisturbed swards. 6Synthesis and applications. Prediction of habitat resilience following disturbance is dependent on which components of the system are investigated. However, data such as that presented here can help land managers understand how palimpsests of current habitat characteristics may have evolved, and how disturbance regimes may be managed in the future. It is likely that the resilience of grasslands such as those on SPTA may have been overestimated, and perceptions of habitat carrying capacity for disturbance events may require re-evaluation. [source] Hemeroby, urbanity and ruderality: bioindicators of disturbance and human impactJOURNAL OF APPLIED ECOLOGY, Issue 5 2002M. O. Hill Summary 1Species vary according to whether they benefit from or are harmed by disturbance and intensive human activity. This variation can be quantified by indices of disturbance and unnaturalness. 2An urban flora was characterized by comparing quadrat data from cities with several large data sets from the countryside. Existing scales of species response to disturbance and unnaturalness, ruderality (a plant's ability to survive in disturbed conditions) and hemeroby (a measure of human impact) were contrasted with derived scales based on the number of associated annuals and aliens and with ,urbanity', defined as the proportion of urban land in the vicinity of each quadrat. 3Species presence data were available from 26 710 quadrats distributed through Great Britain, with urban sites only in central England. Satellite imagery was used to measure the proportion of urban land cover in the vicinity of each quadrat; 2595 quadrats were located in 1-km squares having at least 40% cover of urban land. 4The 20 species having highest urbanity were all alien to Britain, comprising 12 neophytes and eight archaeophytes. 5Of the 20 most frequent species in quadrats situated in 1-km squares with at least 40% urban land cover, 18 were natives. The two exceptions were Artemisia vulgaris , an archaeophyte, and Senecio squalidus , a neophyte. 6Both ruderal and hemerobic species, as usually defined, include many non-urban arable species. The hemeroby scale of Kowarik (1990 ), designed for Berlin, does not work well in Britain. 7The proportion of associated annuals (annuality) and the proportion of associated neophytes (alien richness or xenicity) can be developed into good indices. The annuality scale is very well defined because annuals tend to occur with other annuals. Plants with high annuality are mostly arable weeds. 8Urban specialists in central England are, with a few exceptions, character-species of the phytosociological classes Artemisietea , Galio-Urticetea and Stellarietea . Most of them have numerous non-urban associates and they do not form a very well defined group. They have intermediate levels of annuality combined with relatively high levels of xenicity. 9While it is possible to develop indices of hemeroby, urbanity and ruderality, these concepts are relatively complicated. Annuality and xenicity are simpler measures that can complement Ellenberg values, but definitive values for Great Britain would require additional data from southern England. [source] Factors affecting predation by buzzards Buteo buteo on released pheasants Phasianus colchicusJOURNAL OF APPLIED ECOLOGY, Issue 4 2001R.E. Kenward Summary 1Information on the effects of wildlife predation on game and livestock is required to allow improved management of all organisms involved. Monitoring of prey, predators and predation mechanisms each suggests important methods, illustrated here by data from common buzzards Buteo buteo and ring-necked pheasants Phasianus colchicus. 2Location data from 136 radio-tagged common buzzards, together with prey remains from 40 nest areas, records from 10 gamekeepers and vegetation surveys, were used to investigate raptor predation at 28 pens from which pheasants were released in southern England. 3Among 20 725 juvenile pheasants released in 1994,95, gamekeepers attributed 4·3% of deaths to buzzards, 0·7% to owls, 0·6% to sparrowhawks, 3·2% to foxes and 0·5% to other mammals. 4Fresh pheasant remains were found on 7% of 91 visits to buzzard nests, and 8% of radio-tagged buzzards had significantly more association than other buzzards with pheasant pens. 5Predation by buzzards was most likely to be recorded at release pens with little shrub cover, deciduous canopies and a large number of released pheasants. The number of pheasants killed was greatest in large pens with extensive ground cover, and the highest proportion of released pheasants was killed in large pens where few were released. However, only 21% of 55 releases had > 2 pheasant kills per week. 6Radio-tagged buzzards were located most often at pheasant-release pens with open, deciduous canopies. Pens were most likely to be visited by buzzards that had fledged nearby, but the proximity of buzzard nests had little influence on how much predation occurred. 7Only a minority of buzzards associated frequently with pheasant pens, and predation was heavy at only a minority of sites, where pen characteristics and release factors probably made it easy for individual buzzards to kill pheasants. We suggest that the occasional heavy losses could be avoided by encouraging shrubs rather than ground cover in pens, by siting pens where there are few perches for buzzards, and perhaps also by high-density releases. [source] Isolation of a cyprinid herpesvirus 2 from goldfish, Carassius auratus (L.), in the UKJOURNAL OF FISH DISEASES, Issue 11 2007K R Jeffery Abstract Haematopoietic necrosis virus [cyprinid herpesvirus 2 (CyHV-2)] was isolated during disease outbreaks in goldfish, Carassius auratus, at an ornamental fish retail site in southern England in 2004. Signs of disease included lethargy and inappetence and were first seen after water temperatures increased from 14,15 to 19,21 °C. External gross pathology included pale patches on the gills and skin and internally the spleen was enlarged, often with distinctive white nodules. The most prominent histopathological changes observed were necrotic lesions in the spleen and kidney and focal patches of necrosis in the gill lamellae. Necrotic cells often contained nuclei with marginated chromatin and pale intranuclear inclusions. Ultrastructural examination of the spleen tissue revealed typical herpesvirus-like particles measuring 100 nm in diameter. The virus was isolated from extracts of gill tissue in KF-1 cells at 20 °C and oligonucleotide primer sets were designed based on conserved gene sequences and used to amplify viral DNA by polymerase chain reaction (PCR). The PCR assays were then used to detect the virus in DNA extracted from tissues sampled during earlier disease investigations at the retail site owner's holding facility in 2002 and 2003 and stored at ,70 °C since then. Polymerase gene-specific PCR amplification products obtained from tissue samples and from the virus isolated in cell culture shared 100% nucleotide sequence identity with the published sequence for CyHV-2. [source] Observations of Dermocystidium sp. infections in bullheads, Cottus gobio L., from a river in southern EnglandJOURNAL OF FISH DISEASES, Issue 4 2004S W Feist Abstract Bullheads, Cottus gobio, with macroscopic external cysts on the skin and fins measuring up to 3 mm in diameter were detected in the River Allen and its tributaries in southern England between 1992 and 1998. The prevalence of these cysts was up to 50% at some sites. Examination of cyst contents revealed the presence of numerous spores, typical of the genus Dermocystidium, measuring 8 ,m in diameter. The parasite developed within well-defined cysts, which were located in the hypodermal connective tissues of the host. No cysts were present on the fins of any of the fish examined. Histological examination revealed a cyst wall consisting of an inner layer of dense eosinophilic material similar to that reported for Dermocystidium spp. forming coenocytic hyphae. No evidence was found of systemic infection or hyphal formation. Spores contained a prominent refractile body, which gave a weakly positive reaction for polysaccharides with the periodic-acid Schiff reaction and was positively stained with acidic dyes. Several examples of ruptured cysts were seen in histological sections and in some of these cases the host epithelial layer was breached, allowing release of the spores to the environment. Morphological features of, and host response towards, the Dermocystidium sp. in bullheads are compared with similar infections in salmonids and other freshwater fish species. [source] Floodplain agricultural systems: functionality, heritage and conservationJOURNAL OF FLOOD RISK MANAGEMENT, Issue 3 2010H.F. Cook Abstract Floodplain infrastructural features reduce flood risk and have the potential to enhance habitat, biodiversity, water quality and provide societal benefits. Man-made water management systems common in southern England are both flood tolerant and form part of the functional floodplain. Historic floodplain features should be incorporated into agri-environmental policy, as climate change and increasing climate variability makes flood detention areas ever more desirable. Of major importance are floodplain meadows, grazing marshes, water meadows and riparian vegetation, and there is a trend to restore river channels to more natural conditions. This paper describes the operation of historic floodplain water management systems and considers the features associated with canals and mills. The major themes in achieving conservation and restoration goals are presented, and it is demonstrated that a refinement of policies on the ground is required. [source] Short-term prediction of motorway travel time using ANPR and loop dataJOURNAL OF FORECASTING, Issue 6 2008Yanying LiArticle first published online: 28 MAY 200 Abstract Travel time is a good operational measure of the effectiveness of transportation systems. The ability to accurately predict motorway and arterial travel times is a critical component for many intelligent transportation systems (ITS) applications. Advanced traffic data collection systems using inductive loop detectors and video cameras have been installed, particularly for motorway networks. An inductive loop can provide traffic flow at its location. Video cameras with image-processing software, e.g. Automatic Number Plate Recognition (ANPR) software, are able to provide travel time of a road section. This research developed a dynamic linear model (DLM) model to forecast short-term travel time using both loop and ANPR data. The DLM approach was tested on three motorway sections in southern England. Overall, the model produced good prediction results, albeit large prediction errors occurred at congested traffic conditions due to the dynamic nature of traffic. This result indicated advantages of use of the both data sources. Copyright © 2008 John Wiley & Sons, Ltd. [source] EVALUATION OF THE CONTROLS ON FRACTURING IN RESERVOIR ROCKSJOURNAL OF PETROLEUM GEOLOGY, Issue 4 2005D.C.P. Peacock The style, geometry and distribution of fractures within reservoir rocks can be controlled by numerous factors, including: rock characteristics and diagenesis (lithology, sedimentary structures, bed thickness, mechanical stratigraphy, the mechanics of bedding planes); structural geology (tectonic setting, palaeostresses, subsidence and uplift history, proximity to faults, position in a fold, timing of structural events, mineralisation, the angle between bedding and fractures); and present-day factors, such as orientations of in situ stresses, fluid pressure, perturbation of in situ stresses and depth. The relative timing of events plays a crucial role in determining the geometry and distribution of fractures. For example, open fractures are commonly clustered around faults if the open fractures and faults formed at the same time, but clustering does not tend to occur if the open fractures pre-date or post-date the faults. Understanding these factors requires traditional geological skills, including the analysis of one-dimensional (line-sampling) data from core, borehole images and exposed analogues. This paper reviews the factors that control fractures within reservoir rocks and discusses methods to assess those controls. Examples are presented from Mesozoic limestones in southern England. It is shown that traditional geological skills are of vital importance in determining the rock characteristics, structural and present-day factors that control fractures. [source] | |||||||||||||||||||||||||||||||||||||