bluuebunny/crossref_metadata_2025 huggingface dataset:
Clarification requests and the language-impaired child
Authors: Porter Ruth , Conti-Ramsden Gina
Published: November 2007

The frequency, structure and sophistication of clarification requests with in a mother—language-impaired child dyad were examined. The mother— child dyad was videotaped in free-play situations before and after the onset of therapy. The data indicated that the clarification request was a consistent feature of both mother and child's interactive style. Both members of the dyad equally shared the floor for initiating clarification requests, both were usually successful in obtaining clarification, and both used a limited number of the clarification request categories. A developmental trend was observed. Remedial implications are discussed.
Clinical applications of recasting : review and theory
Authors: Watkins Ruth V. , Pemberton Elizabeth F.
Published: November 2007

Recasts have been shown to be successful in promoting the language development of normal children. A RECAST is a discourse adjustment through which basic semantic information is retained while syntactic structure is altered. Little research to date has addressed the power of recasts in advancing the development of specifically language-impaired children. The language-impaired child is believed to be delayed, but not deviant from the normal child, in acquiring language. For this reason, it is suggested that the same kind of linguistic input beneficial to normal children should be beneficial to language-impaired children. This paper includes a review of the literature on the effects of recasts on normal language acquisition. The rare event cognitive comparison model (Nelson, 1980; 1987) is presented in an attempt to describe how a child might use recasts to help acquire language. Finally, a section on the potential use of recasts to aid in the development of language-impaired children is presented.
Helping the development of consonant contrasts: a case study
Authors: Jarvis Joy
Published: November 2007

This study details speech work undertaken with a partially-hearing child who had difficulty using appropriate consonant contrasts. It illustrates the methods which were used to develop skills at both the phonetic and the phonological level. The emphasis was on helping the child to use his phonological system more appropriately, and the change in this system over six months is described.
'Writing frames' for children with expressive language problems
Authors: Grauberg Eva
Published: November 2007

The article deals with one way of helping children with expressive language problems when they make their first attempts at 'free writing'. It is suggested that structure and creativity can be combined by using 'grammatical writing frames' within which the children can express some of their own ideas on specific topics. A group lesson is described, the advantages and dis advantages of the technique are discussed, and a summary of steps to be taken by the teacher is given. The appendix contains three examples of 'frames'.
Effectiveness of language elicitation tasks with two-year-olds
Authors: Landa Rebecca M. , Olswang Lesley B.
Published: November 2007

One unstructured and two structured language sampling conditions were compared to determine the ways in which different types of structure would affect 2-year-olds' productions of the possessor + possession semantic relation. In the unstructured, naturalistic condition, the clinician followed the child's lead and responded in ways that would encourage the produc tion of the possessive construction. In the structured conditions, the clinician utilized wh-questions and sentence completion tasks to elicit the possessive construction. While the subjects produced a greater quantity and diversity of possessive constructions in the structured conditions, no differences were observed between the two types of linguistic elicitation techniques. Implications for sampling language with young children are discussed.
Treating 'cleft palate speech': combining phonological techniques with traditional articulation therapy
Authors: Grunwell Pamela , Dive Denise
Published: November 2007

The relative merits of traditional articulation therapy and phonological approaches to the treatment of 'cleft palate speech' are discussed. It is suggested that contrary to customary clinical practice, phonological therapy is an appropriate and in some instances essential procedure in such cases. Two case studies are described in support of this proposal.
Teachers' responses to children with severe learning difficulties: integrated versus segregated settings
Authors: Taylor Janet , Conti-Ramsden Gina
Published: November 2007

The present study aimed to investigate the linguistic environment provided by teachers for children with severe learning difficulties. Teachers' responses to three normal ability pupils and five children with severe learning difficulties were examined in segregated and integrated nursery settings. Results revealed similarities in the distribution of teachers' responses between the normal ability pupils and the severe learning difficulty pupils in integrated settings. Children with severe learning difficulties were responded to differently in segregated settings. The implications of these results for the conversational development of children with severe learning difficulties are discussed.
On the occurrence of okay i n therapy
Authors: Kovarsky Dana
Published: November 2007

Within the training setting, supervisors may tell their apprentice clini cians not to use the word okay too often during therapy. While analysing two videorecorded, individualized therapy lessons involving an ASHA-certified speech-language clinician, okay was frequently found in the speech of the therapist. It was discovered that okay served a variety of releasing and evaluative functions, within various levels of the discourse, which appeared to manifest role differences between the therapy lesson participants.
Semantic-pragmatic language disorder: a description with some practical suggestions for teachers
Authors: Smedley Martin
Published: November 2007

This article outlines the main characteristics of semantic-pragmatic language disorder, and suggests ways in which the teacher can complement oral language therapy through written work. Approxi mately 85% of the semantic-pragmatic language-disordered children who have been at John Horniman School over the last three years have been able to cope with most of these activities. A reading age of about 6;6 years will be necessary for children to attempt many of the activities suggested in the article.
Maintaining reading-disabled students' attention during reading instruction
Authors: Lindsey Jimmy D. , Cheek Earl H. , Kritsonis Diane
Published: November 2007

This paper provides a brief review of the professional literature as it is related to reading-disabled students and their inability to maintain attention during reading instruction. Factors that can cause or contri bute to reading-disabled pupils' inability to attend during reading are delineated General strategies which reading teachers and specialists can use to increase their disabled readers' attention are described Also, specific instructional techniques that educators can use to facilitate reading-disabled students' attention during instruction are noted.
Facilitating speech development: a case study
Authors: Grunwell Pamela , March Elizabeth , Russell Jane
Published: November 2007

This case study describes the speech development of a boy (G) between the ages of 1;7 and 4;0. During this period G was receiving intensive speech therapy to facilitate his speech development as it was evident that he had difficulties learning to pronounce. G was given therapy at such an early age and intensively because his mother is a speech therapist. Treatment techniques are described in detail. The implications for speech therapy practice are discussed.
One class at a time: a case study of phonological learning
Authors: Stone Judith R. , Stoel-Gammon Carol
Published: November 2007

This article describes S, a phonologically-disordered preschooler who demonstrated an unusual learning style during ten months of treatment. She had an apparent preference for learning one new phonological pattern at a time, progressing to near mastery on a given pattern before beginning development of a new one. This 'one pattern at a time' approach affected both treated and untreated patterns. The role of treatment in triggering S's phonological growth is discussed, and hypotheses are offered as to the possible factors contributing to S's learning style and developmental sequence.
Modifying abnormal tongue patterns in an older child using electropalatography
Authors: Gibbon F. , Hardcastle W. , Moore A.
Published: November 2007

This case study describes the investigation and treatment of a child with abnormal production of /s/ and lzl, using the instrumental technique of electropalatography (EPG). Children such as the one described can be resistant to treatment using conventional approaches, with the result that the difficulties may persist for years. EPG appears to be a potentially valuable tool that provides the clinician with more detailed information on tongue/palate contact, and offers the client important visual feedback for instantaneous monitoring, which helps to establish permanent modification of tongue placement patterns.
Profiling teacher/child classroom communication: reliability of an alternating time sampling procedure
Authors: Brunson Kelli W. , Haynes William O.
Published: November 2007

Reliability of an on-line, alternating time sampling (A TS) procedure was examined for evaluating classroom communication acts. Fifteen limited-language children were videotaped during classroom activities while two trained judges simultaneously coded teacher/child com munication acts on-line. Judges systematically alternated attention from child to teacher each minute during sampling. Analyses revealed high interjudge reliability for live coding and high agreement between A TS and continuous coding on all measurements. ATS appears practical for classroom assessment and measurement of treatment effects.
Music with special needs children: a powerful aid
Authors: Addison Richard
Published: November 2007

The author begins by looking at the value of music and its contribution to the whole curriculum, as seen by the National Curriculum Music Working Group. He compares these lofty aspirations with the all too frequently met reality of fairly routine music teaching. But he goes on to show how the aspirations can easily be achieved, and how he has tried to achieve them in his work with language-impaired and other slow learning children. Great emphasis is laid on pupil choice and responsi bility in all activities. The benefits upon children of the right kind of musical activity can be observed, if not measured.
Gaining group cooperation through role playing
Authors: Flaherty Carol
Published: November 2007

School-based speech-language pathologists who give language develop ment instruction to classrooms of adolescent students can increase effective communication skills through cooperative role play procedures and, subsequently, decrease behavioural difficulties. This paper reports on an 18-week project based on these procedures.
Word learning in language-impaired children
Authors: Gathercole Susan E.
Published: November 2007

The nature of the word-learning deficits of children with developmental language disorders are analysed in this article. Experimental studies of word learning with language-disordered groups demonstrating a clear phonological long-term learning locus to the word-learning problems of this population are reviewed. It is argued that the severe phonological working-memory impairments of such children play an important role in the difficulties they encounter in learning the phonological forms of new words. Finally, possible techniques for remediating phonological memory deficits are discussed.
Connections between phonology and semantics: an exploration of lexical processing in a language-impaired child
Authors: Chiat Shula , Hunt Jon
Published: November 2007

This is a study of lexical processing in a 6-year-old whose spontaneous output shows word-finding problems, phonological errors, and occa sional semantic errors. In order to investigate the level(s) of processing responsible for these errors, tasks tapping different stages of input and output processing were carried out. The child's responses showed that his errors were largely confined to output, and involved phonological deviation from the target. Responses to different output tasks showed similar types of errors, but some inconsistency in the treatment of particular phonological or lexical targets. The implications for the nature of the processing impairment and for intervention are discussed.
Learning past tense morphology with specific language impairment: a case study
Authors: Eyer Julia A. , Leonard Laurence B.
Published: November 2007

This paper presents a case study of a child with specific language impairment who usually omitted the regular past inflection in obligatory contexts yet occasionally over-regularized the past (e.g. *blowed). A treatment approach was employed that permitted a test of one current account of this paradoxical pattern, the filled paradigm' hypothesis. The child's gains over the treatment period did not conform to the predic tions of the hypothesis, but rather suggested the possibility that her use of the past tense inflection was related to the phonological properties of the verb stem.
Developmental cognitive neuropsychology: a comparison of two case studies
Authors: Bryan Alison , North Clare
Published: November 2007

This paper is an attempt to apply a developmental cognitive neuro- psychological approach to two specific language-impaired children. The resulting profiles enable hypotheses to be made about the principal areas of processing difficulty and the effect these could have had on develop ing language skills.
Successful treatment of selective mutism: collaborative work in a secondary school setting
Authors: Watson Sarah
Published: November 2007

This article describes the successful treatment of a single case of selective mutism. The client is a teenage girl with moderate learning difficulties. Issues surrounding the role of the speech and language therapist in a case such as this are discussed. The nature of collaborative work within the school is described, together with practical ideas used for both supporting staff and parents and actual treatment of the client.
Language screening at 18-36 months: the First Words and First Sentences Tests and the First Words Comprehension Cards
Authors: Gillham Bill , Boyle James , Smith Nicola , Cheyne Bill
Published: November 2007

This paper describes the development of screening tests assessing receptive and expressive vocabulary and first word combinations which are intended to discriminate maximally amongst the bottom 15% of the age-range 18-36 months. Underlying technical and theoretical issues are discussed, which point to the powerful validity of these new tests.
An intervention for enhancing children's understanding of jokes and riddles
Authors: Ezell Helen K. , Jarzynka Melanie A.
Published: November 2007

An intervention was conducted for teaching children a strategy for understanding and explaining the humour in lexical jokes. Two typical 7-year-olds and two students with learning disabilities, ages 9 and 11, participated in the training. A multiple probe design across joke sets and across children was used. Results showed that all children mastered the

strategy and learned to explain lexical jokes. Limited generalization of this strategy to untrained jokes occurred; however, generalization increased significantly after children gained more knowledge of multiple word meanings through follow-up semantic training. Clinical implica tions are discussed.
Speech therapy with a group of hearing-impaired adolescents. III. Duration of vocalizations and length of utterances in therapy sessions
Authors: Bench John , Maloney Cathy , Backhouse Roxanne , Heine Chyrisse
Published: November 2007

Speech therapy conversations between five dyads, consisting of senior speech pathology students and hearing-impaired adolescents enrolled in a Total Communication programme, were videorecorded for five weekly sessions. Samples over one-minute intervals at the start, middle, and end of the sessions were analysed for durations of vocalizations (to the nearest 0.1 second) and for lengths of utterances (by morphemic counts). Statistical analyses examined differences between dyads, conversational partners, sessions, and intervals, and the related interactions. The impli cations of the outcomes for speech therapy instructionlintervention pro grammes are discussed.
A developmental cognitive neuropsychological approach to the assessment of information processing in autism
Authors: Hurd Angela
Published: November 2007

This paper explores the application of the cognitive neuropsychological model to two children within the autistic spectrum. Both children were assessed individually over five sessions in an attempt to establish their strategies for information processing. Different input modes were com pared in combination and in isolation - the spoken word, sign, and print. The results offer insights into their processing, highlighting indi vidual differences, which led to subsequent hypotheses for optimum teaching approaches.
How shall we be judged? Speech and language therapists in educational settings
Authors: McCartney Elspeth , van der Gaag Anna
Published: November 2007

Speech and language therapists are under ever-increasing pressure to demonstrate the value of their work, both in terms of cost to the pur chaser and benefit to the client. The work of these therapists in school settings differs significantly from their work in health-care settings, not least because of strong philosophical and organizational differences between health and education. This paper argues that the methods developed within the field of educational research are amongst the most productive in the investigation of effectiveness. It provides details of a multidimensional model which could be applied in educational settings.
Nanotechnology and Social Context
Authors: Sandler Ronald
Published: November 2007

The central claims defended in this article are the following: (a) The social and ethical challenges of nanotechnology can be fully identified only if both the characteristic features of nanotechnologies and the social contexts into which they are emerging are considered. (b) When this is done, a host of significant social context issues, or issues that arise as a result of problematic features of the social contexts into which nanotechnology is emerging, become salient. (c) These issues can only be addressed by remedying the problematic features of the social contexts, which cannot be accomplished by technology design or risk management alone. (d) The U.S. National Nanotechnology Initiative's conceptualization and operationalization of responsible development does not adequately recognize the significance of social context issues to responsible development. (e) Therefore, the National Nanotechnology Initiative is not yet comprehensive and needs to be expanded with respect to identifying and addressing social context issues.
Cyberpunk Cities
Authors: Abbott Carl
Published: November 2007

The science fiction subgenre of cyberpunk developed in the 1980s and 1990s with a strong interest in urban settings. A reading of important cyberpunk novels shows the way in which the ideas of formal urban theory, such as the idea of global cities, cities as communication systems, and the Los Angeles school of urban studies, have been incorporated into this facet of popular culture. The analysis suggests that science fiction can help planners to understand the influence of a range of social theories on public understanding of planning issues.
Toward a Sustainable Relationship between City and University
Authors: Russo Antonio P. , van den Berg Leo , Lavanga Mariangela
Published: November 2007

While the impact of knowledge assets on regional economies receives much attention in the economic literature, management and planning issues regarding the relationships between academic and local agents are underinvestigated. In this article, it is argued that universities could be a driving force for urban development, provided cities succeed in embedding knowledge in the local social and economic networks, which is seen to depend to a large extent on the balance in the process of exchange between the various stakeholders of higher education: students and academic communities, entrepreneurs, and local communities. A model of sustainable city-university relationship is proposed and matched with evidence from nine case studies of European cities hosting a large higher education sector; the role of policy and planning to sustain and enhance such links is also brought to the fore through the illustration of various best practices in the case studies.
Liver and kidney function tests amongst paint factory workers in Nkpor, Nigeria
Authors: Orisakwe O.E. , Nwachukwu E. , Osadolor H.B. , Afonne O.J. , Okocha C.E.
Published: November 2007

Lead, cadmium, nickel and other industrial metals used as part of paint varnishes have been reported to have adverse health implications. An evaluation study on some toxicological effects of occupational exposure to paint, among 25 occupationally exposed artisans and 25 students (control) of Ichi Technical College, Ichi Ekwusigo Local Government Area, Anambra State, Nigeria was carried out. Heavy metals were analysed by atomic absorption spectrophotometry and standard assay procedures were employed for biochemical parameters. The biochemical indices used include serum electrolytes urea, creatinine, alanine (ALT) and aspartate aminotransferases (AST), alkaline phosphatase (ALP), conjugated and total bilirubin. Others include blood lead, serum cadmium and nickel. Our results showed that occupational exposure of humans to paints increased the blood lead (39 ± 4 μg/dL), serum cadmium (13 ± 1 μg/dL) and nickel (63 ± 1 μg/dL), when compared with non-paint factory workers (PFW) lead (17 ± 4 μg/dL), serum cadmium (9 ± μg/dL) and nickel (25 ± 44 μg/dL), significantly at P < 0.05 lower values were observed for serum sodium (138.96 ± 0.58mmol/L), bicarbonate (26.88 ± 0.39 mmol/L), urea (3.15 ± 0.13 mmol/L) and creatinine (80.48 ± 1.04 μmol/L) for paints factory workers when compared with non-paint factory workers, sodium (139.84 ±0.62mmol/L), bicarbonate (26.20 ±0.22mmol/L), urea (3.44 ± 0.11 mmol/L) and creatinine (80.40 ± 1.55 μmol/L); at P > 0.05. The activities of AST (10.36 ± 0.58 μ/L), ALT(8.76 ± 0.47 μ/L) and ALP (47.12 ± 3.33 μ/L) in PFW were slightly elevated compared with non-PFW. Our result indicates that occupational exposure of humans to heavy metals in paints may have long term deleterious effects on liver and renal functions. In conclusion, it should be noted that occupational exposure to cadmium or lead among PFW, may compromise the liver and renal functions in man. Toxicology and Industrial Health 2007; 23: 161—165.
Overview and Scrutiny as a Dialogue of Accountability for Democratic Local Government
Authors: Martin Jane
Published: November 2007

The Local Government Act 2000 established a new set of political arrangements across England and Wales which included, for the first time, a distinct, separate overview and scrutiny function with the statutory duty to 'hold the executive to account'. This paper will explore the potential and limits of the overview and scrutiny function as a mechanism for public accountability in local government. It will be argued that effective processes of public scrutiny (as mechanisms for public accountability) are an essential component of good local governance with the potential to reconnect local citizens and the state within modernised forms of representative democracy. Reflecting current policy debates, it will be suggested that the future role of the local authority, as the democratically elected local tier of government, should be to create the conditions for public accountability in local governance and support officers and members engaged in public scrutiny.
The social health care policy implementation gap: moving beyond the legacies of 'new' public management
Authors: Lincoln Marisa G.
Published: November 2007

How do social health care policies fare within economically rational structures? This paper, based on a study of two Scottish maternity units, identifies and explains a number of gaps in social health care policy implementation and practice. One finding suggests that devolved budgets result in a certain amount of operational fragmentation, increased attention to cost consciousness, low staffing levels and ultimately a noticeably decreased concern for social health care policy implementation. What can be done to ensure that health and welfare services are democratized? This paper proposes that moving beyond new public management involves an alternative model which would encompass a broadened form of economic regulation. Such a model would ensure that health and welfare outcomes are comprehensively accounted for in financial terms. There are strong indications that subjective service user indicators of health and welfare are just as important as objective professional assessments. Another indication is that whereas technological determinism sparks off rising costs, service user self-determination and self-management, which situates medical expertise at the periphery rather than the centre, could save public money. Thus, the need to widen the economic base serves both the objectives of the treasury and the needs of the public.
Sorted circles, relative-age dating and palaeoenvironmental reconstruction in an alpine periglacial environment, eastern Jotunheimen, Norway: lichenometric and weathering-based approaches
Authors: Cook-Talbot Judith D.
Published: November 2007

Lichenometric and weathering-based techniques are employed in an investigation of the chronology of large-scale sorted circles in Jotunheimen, southern Norway. Comparison of diameter measurements of Rhizocarpon geographicum agg. with local growth curves, and size-frequency analysis of lichen population data, indicate that all the sorted circles originated prior to the mid-eighteenth century 'Little Ice Age' maximum. Parts of the circle borders appear to have been stable since before the twelfth century, although minor disturbances to border clasts were widespread between about AD 1640 and 1740. Large proportions of the smaller surface clasts in circle centres have stabilized only since the 'Little Ice Age' maximum. The thickness of surface weathering rinds and measurements of rock surface hardness (R-values obtained using a Schmidt hammer) indicate long periods of clast exposure in circle borders (at least 1500 years at some sites) and shorter exposure times for central clasts. Despite difficulties in inferring the nature of rind thickness/age and R-value/age curves, the evidence based on weathering criteria strongly points to early Holocene origins. These results demonstrate the potential for using relative-age dating techniques in chronological and palaeoenvironmental investigations of sorted patterned ground, and suggest that a similar approach may be applicable in studies of other stony periglacial features.
Modern pollen-rain data from South and Central America: a test of the feasibility of fine-resolution lowland tropical palynology
Authors: Bush Mark B.
Published: November 2007

Modern pollen rain data from a suite of sites in lowland South and Central America are analysed by means of detrended correspondence analysis (DCA) and two-way indicator species analysis (TWINSPAN), and are shown to have discernible characteristics for major vegetation types: varzea, igapo, semi-deciduous, cerrado and terra firme forest. Data analysis demonstrates the potential for detailed palaeoclimatic reconstructions of lowland tropical environments, but also demonstrates the danger of making generalizations about palaeoecosystems based on few palaeoecological records.
On the accuracy of lichenometric dates: an assessment based on the 'Little Ice Age' moraine sequence of Nigardsbreen, southern Norway
Authors: Bickerton Richard W. , Matthews John A.
Published: November 2007

Families of lichenometric dating curves are constructed using four historically-dated moraine ridges on the glacier foreland of Nigardsbreen (Jostedalsbreen ice cap), southern Norway. A further 20 'Little Ice Age' moraine ridges are dated in terms of median-predicted dates derived from the families of curves. Four approaches are used to assess the accuracy of the median-predicted dates: (1) the extent to which the dates form a temporal sequence; (2) the extent to which they agree with local independent evidence of glacier variations; (3) the extent to which dates agree when the moraine sequences on the two sides of the glacier foreland are dated separately; and (4) the extent to which they agree when section Rhizocarpon is differentiated from lichens of the Rhizocarpon subgenus as a whole. It is concluded that under conditions favourable for lichenometric dating, median-predicted dates have attained an accuracy of ~10% on the 'Little Ice Age' timescale. Realistic error limits are considered to be of the order of ±20 years for the oldest moraines and ±5 years for the youngest. Previous dates for the Nigardsbreen moraine sequence derived from single lichenometric dating curves may be ~5% less accurate. It is suggested that the range of predicted dates obtained from families of lichenometric dating curves can be used as a conservative surrogate for accuracy.
Decadal timescale links between Antarctic Peninsula ice-core oxygen-18, deuterium and temperature
Authors: Jones P.D. , Marsh R. , Wigley T.M.L. , Peel D.A.
Published: November 2007

The Antarctic Peninsula region has exprienced a long-term warming trend over the twentieth century, with the 1971-90 mean at Faraday being 1.9°C warmer than the mean over 1903-41 based on expedition reports. For the period prior to 1900, there is conflicting evidence from different data sources. An initial interpretation of isotopic data from ice cores suggests that the nineteenth century was warmer than the twentieth century. In contrast, snow accumulation rate data for the nineteenth century from the same ice cores suggest lower temperatures. Here we investigate these facts by studying the links between atmospheric temperature over the Antarctic Peninsula, circulation parameters and isotopic data over the period of instrumental records. We show that the relationships between these variables are complex and highly spatially variable. In particular, the correlations between temperature and δ 18O and δD are generally of the order r = 0.5 or less on timescales of one to five years. Conflicts between evidence from accumulation rate and isotopic data appear to reflect the influence of source-region effects on the isotope records. To unravel the complex isotopic records available for the Peninsula region better; additional cores must be analysed for both δ 18O and 8D at the same site.
A 2000-year lichen-snowkill chronology for the Colorado Front Range, USA
Authors: Benedict James B.
Published: November 2007

Measurements of Rhizocarpon subgenus Rhizocarpon thalli in fixed-area (100-m 2) sample plots at 295 randomly selected localities above timberline in the Colorado Front Range suggest six episodes of widespread, shallow, lichen snowkill during and immediately following the Audubon glacial interval. Recolonization of lichen-free areas began in cal. AD 210, 375, 570, 700, 1025, and 1255. In contrast to the 'Little Ice Age', when snowkill was restricted to narrow bands peripheral to modern late- lying snowpatches, Audubon snowkill destroyed all crustose lichens in more than 90% of the study area. Heavy April or May snowstorms, occurring after redistribution of snow by wind had diminished, are thought to have been responsible; cool, cloudy summers and warm subnivean winter temperatures may also have been involved. Audubon snowkill episodes lasted for relatively brief periods, and were superimposed on the broader pattern of late-Holocene climatic change. They did not necessarily trigger glaciation or cause geomorphic instability, but are thought to have temporarily discouraged human use of the Front Range alpine region through their adverse effects on large-game-animal populations. Lichenometric dates for landforms in areas of potential snowkill should be evaluated using rock- weathering criteria or other independent age evidence.
Reflections on COHMAP
Authors: Wright H.E. , Bartlein P.J.
Published: November 2007

COHMAP (Cooperative Holocene Mapping Project) had its start in the 1970s with the intent to compare atmospheric general circulation models with quantitative palaeoclimatic reconstructions based on stratigraphic pollen analysis. As the sophistication of the models increased and as additional palaeoclimatic indicators (lake levels, marine microfossils) were incorporated in the reconstructions, the programme expanded to global coverage through the participation of numerous collaborators. The carefully nurtured dual approach of modelling and data analysis was strengthened by continued testing of one against the other, with emphasis on interdisciplinary understanding fostered by workshops. With the development of new computer models that have higher spatial resolution and improved boundary conditions, and with diversification and enlargement of the geographic and temporal coverage of field and analytical data, substantial refinements can be anticipated in the understanding of global climatic changes since the last glacial maximum.
An early-Holocene pollen, mollusc and ostracod sequence from lake marl at Llangorse Lake, South Wales, UK
Authors: Walker M.J.C. , Griffiths H.I. , Ringwood V. , Evans J.G.
Published: November 2007

An integrated analysis of molluscs, ostracods and pollen is presented from early Holocene lake marl at Llangorse Lake, Powys, South Wales. The mollusc and ostracod records reflect a littoral environment with increasing eutrophic conditions and a progressive shallowing of lake waters, although the record does not begin until around 9600 BP, probably due to the isolated location. The pollen profile provides evidence of both local and regional vegetational changes over the first two millennia of the present interglacial. Following climatic amelioration at the beginning of the Holocene, there was rapid colonization by trees and shrubs, with juniper widespread by 9800 BP, birch woodland by 9500 BP, and pine by 9300 BP. Late in the ninth millennium BP, hazel became established, to be followed during the course of the eighth millennium by elm and oak. There are indications in both the pollen and molluscan/ ostracod sequences of a relatively dry climatic regime during the early Holocene, while the pollen record suggests a short-lived climatic cooling in the middle of the tenth millennium BP.
The use of chironomid remains for AMS 14C dating of lake sediments
Authors: Jones V.J. , Battarbee R.W. , Hedges R.E.M.
Published: November 2007

Chironomid remains from lake sediments can be used as a source of carbon for AMS (accelerator mass spectrometry) 14C dating. Four chironomid AMS dates were obtained from the Round Loch of Glenhead and compared with conventional bulk dates. Results showed chironomid dates to be younger than their conventional equivalents, although the chironomid series included a dating inversion. Nevertheless these preliminary results indicate the potential of this carbon source for dating, and provide a unique application of the AMS dating method. This technique may be useful where conventional dates are adversely affected by older allochthonous carbon. However, further evaluation is required, including testing chironomid dates against sediments of known calendar age.
Late-Holocene changes in sea level and environment on eastern Cape Breton Island, Nova Scotia, Canada
Authors: Miller Kristina R. , Livingstone Daniel A.
Published: November 2007

The late-Holocene history of a coastal basin in Otter Harbour on the Great Bras D'Or of Cape Breton Island, Nova Scotia was reconstructed using micro- and macrofossils. The pollen stratigraphy shows a decrease in oak and pine pollen percentages around 4000 BP, while Tsuga pollen reaches a maximum. Over the last 1000 years, genera of the mixed hardwood forest have declined while boreal genera have increased, suggesting climatic cooling in the region. Human influence from 400 BP to the present is evidenced by increased pteridophyte spores and pollen of Rumex, Gramineae, and Ambrosia.

Siliceous microfossils indicate that sea level in the Great Bras D'Or rose over the last 4000 years to 1.5 m below present level at 950 BP. This rate of sea-level rise, 16 cm per century, falls within the regional range of relative sea-level rise in the Maritimes of 10-30 cm per century for the last several thousand years. However, this long-term rate in the Maritimes is less than the rate of 30-35 cm per century determined from local tide gauges over the last hundred years. The discrepancy between these two rates can probably be attributed to recent changes in the eustatic or tectonic components of sea- level rise in this region.
The submerged Pre-Pottery Neolithic water well of Atlit-Yam, northern Israel, and its palaeoenvironmental implications
Authors: Galili Ehud , Nir Yaacov
Published: November 2007

The recent discovery of a vertical open shaft, identified as a well of the Pre-Pottery Neolithic period, was found in a large submerged village off the Atlit promontory, northern Israel. This well indicates that the exploitation of groundwater through wells commenced at the beginning of the eighth millennium BP or possibly earlier. The well lies some 10 m below present sea level, a few hundred metres off the Carmel coast. It is almost 1.5 m in diameter, and some 5.7 m in depth, which proves that the top of the well has been around 5 m above the contemporaneous sea level, i.e., that sea level of the Carmel coast was some 16 m below present sea level at c. 7900 BP. Its fill provides evidence of the surrounding fauna and flora, and the material culture of coastal Neolithic communities. The prevailing hydrological conditions provide important information on ancient sea levels at the end of the post-last- glaciation transgression. Rates of sea-level rise at the period of the village occupation is estimated to be in the order of 15-20 mm yr-1, which is a high figure.
Impact of Euro-American settlement on a riparian landscape in northeast Iowa, midwestem USA: an integrated approach based on historical evidence, floodplain sediments, fossil pollen, plant macrofossils and insects
Authors: Baker R.G. , Schwert D.P. , Bettis E.A. , Chumbley C.A.
Published: November 2007

European settlement and attendant forest clearance and agricultural activities in northeastern Iowa caused changes in the landscape, vegetation, insect fauna and water quality unequalled in rate and magnitude since the melting of Wisconsinan glaciers. Historical documents show that the upper part of the Roberts Creek drainage basin was settled between AD 1840 and 1856, and the area was under intensive cultivation by 1880. Extensive soil erosion beginning at this time resulted in increased runoff and more frequent flooding; aggradation rates increased by one to two orders of magnitude over those in presettlement times, and the entire floodplain was covered with up to 1 m of sediment. Channel widening between about 1880 and 1930 allowed the stream to accommodate greater floods, overbank deposition decreased, and further deposits were restricted mostly to the channel belt.

The presettlement vegetation was a stable mix of wet meadows and riparian shrubs on the floodplain, a rich aquatic community in the stream, and oak savanna on the valley walls and upland. Disturbance from soil erosion, floodplain erosion and floodplain deposition almost completely replaced both lowland and upland communities with ruderal (disturbed ground) plants, many of them introduced weeds. Regional insect communities were simultaneously affected by changes in land use. The presettlement aquatic beetle fauna was dominated by species of dryopoid beetles that today inhabit only streams of high water quality. Terrestrial beetle taxa included species of undisturbed grasslands and riparian forest. The changes in the landscape resulted in a decrease in the diversity of terrestrial beetle taxa and caused the near total elimination of dryopoid beetles in stream waters. Dominating the historic assemblages are beetles associated with dung, polluted waters and cultivated plants, including host-specific immigrant beetle species that are associated with immigrant plant species.
A pollen diagram from the northeast Peloponnese, Greece: implications for vegetation history and archaeology
Authors: Atherden Margaret , Hall Jean , Wright James C.
Published: November 2007

A pollen diagram is presented for a sediment core from Kleonai in southern Greece. A set of seven radiocarbon dates suggests that the core spans the time period from the beginning of the Holocene to the Roman period. Pollen preservation in the core is patchy and there are only three zones on the pollen diagram with countable quantities of pollen. These zones correspond with the early Neolithic, Bronze Age and Roman periods. The area around the site was largely open by the Neolithic but the wider landscape was still well wooded. In the Bronze Age and Roman periods, there is evidence for arable agriculture, including olive cultivation. By the Roman period, most of the semi-natural woodlands had disappeared and the landscape was probably not unlike that of the present day.
'Little Ice Age' summer temperature variations: their nature and relevance to recent global warming trends
Authors: Bradley Raymond S. , Jonest Philip D.
Published: November 2007

Climatic changes resulting from greenhouse gases will be superimposed on natural climatic variations. High-resolution proxy records of past climate can be used to extend our perspective on regional and hemispheric changes of climate back in time by several hundred years. Using historical, tree-ring and ice core data, we examine climatic variations during the period commonly called the 'Little Ice Age'. The coldest conditions of the last 560 years were between AD 1570 and 1730, and in the nineteenth century. Unusually warm conditions have prevailed since the 1920s, probably related to a relative absence of major explosive volcanic eruptions and higher levels of greenhouse gases.
'Little Ice Age' aridity in the North American Great Plains: a high-resolution reconstruction of salinity fluctuations from Devils Lake, North Dakota, USA
Authors: Fritz Sherilyn C. , Engstrom Daniel R. , Haskell Brian J.
Published: November 2007

The 'Little Ice Age' was an interval between about AD 1500 and 1850, characterized by advancing glaciers in mountainous regions of Europe and western North America. However, it is unclear whether this cool moist period was truly global in extent, or how it was manifested in other regions with different climatic controls. A high-resolution reconstruction of salinity fluctuations in Devils Lake, North Dakota, based on fossil diatoms, ostracode-shell geochemistry, and bulk-carbonate geochemistry, indicates that saline conditions prevailed throughout much of the recent past. These results suggest an arid climate in the northern Great Plains throughout the 'Little Ice Age' and that during this interval climatic gradients between the Great Plains and regions to both the east and west may have been quite steep.
A palaeolimnological test of the influence of Norway spruce (Picea abies) immigration on lake-water acidity
Authors: Korsman Tom , Renberg Ingemar , Anderson N. John
Published: November 2007

The effect of recent land use and subsequent vegetation changes per se on surface-water acidity is difficult to ascertain because of the complicating factor of enhanced levels of anthropogenic acid deposition that occurs at the same time as land-use changes. Expansion of conifers is a major contemporary vegetation change in Sweden and other countries. The immigration of Norway spruce (Picea abies (L.) Karst.) into Sweden about 3000 years ago provides, however, a suitable means of assessing the acidification ability of spruce per se on surface waters.

Pollen analysis was used to identify the arrival of spruce in the catchments of eight acid-sensitive Swedish boreal-forest lakes. pH and dissolved organic carbon (DOC) were inferred from diatom assemblages for time periods covering some hundred years before and after the establishment of spruce. Redundancy analysis (RDA) was used to assess whether catchment vegetation had significant effects on the diatom assemblages. At four sites there were significant changes in the diatom assemblages associated with the arrival of spruce, but none of the lakes acidified. At three sites, however, diatom- inferred DOC increased with the arrival of spruce, probably as a result of the accumulation of raw humus.
Climatic variations in western Europe and China, AD 1645-1715: a preliminary continental-scale comparison of documentary evidence
Authors: Pfister Christian , Yan Zhongwei , Schüle Hannes
Published: November 2007

Instrumental and proxy data series from historical archives are compared over the period of the Maunder Minimum (AD 1645-1715) for western Europe (central England, Paris and Switzerland) and China. Winters became colder and drier over the late seventeenth century in western Europe. In China, however, winters were coldest around AD 1650 and became warmer and stormier over the subsequent decades. A significant warming of winters is observed around AD 1700, which, in Paris, corresponds to an increase in zonal wind frequency and a decrease in dust frequency in China. Summers during the late seventeenth century were rather dry in China and moderately wet in western Europe. These trends reversed around AD 1700, when summers became wetter in China and somewhat drier in western Europe. An approach to analysing seasonal anomalies is outlined based on a synoptic interpretation of historical weather charts derived from multi-proxy mapping.
A Holocene pollen record for the Kalahari Desert of Botswana from a U-series dated speleothem
Authors: Burney David A. , Brook George A. , Cowart James B.
Published: November 2007

A 61 cm core through a speleothem column in Drotsky's Cave, Botswana, has yielded a U-series dated pollen record of Holocene vegetation changes in the Kalahari Desert. Between c.10000-7000BP, the site was surrounded by an arid grassland with dry-adapted trees and shrubs such as Acacia and Commiphora. An increase in pollen of Combretaceae and Cyperaceae, and the appearance of pollen of such mesic savanna plants as Grewia between c. 7000—6000 BP, may indicate the onset of slightly wetter conditions. Combretaceae and other mesic pollen types increase between c. 6000-3000 BP, but the late Holocene record appears variable, with the period c. 5000-4000 BP being somewhat dryer than the millennia before and after. It would appear that Kalahari vegetation has changed less during the Holocene than many other African environments previously investigated. Despite the limitations imposed by pollen analysis of cave sites, the record from Drotsky's Cave shows good agreement with regional trends derived from other studies. The use of U-series dated pollen spectra derived from speleothems holds potential for expanding the geographic scope of palynological studies to areas lacking suitable lakes and bogs, and for extending the dated pollen record back an order of magnitude beyond the 14C timescale.