Antarctic glaciology and meteorites

The state of knowledge of meteorites and glaciology is summarized, and directions for research are suggested.by Colin Bull and Michael E. Lipschutz.Contributions from oxygen isotope studies to paleoclimatology and the knowledge of ice flow conditions / Grootes, P.M. -- Weathering effects in antarctic meteorites / Lipschutz, Michael E. -- Mineralogy and petrology of unique and rare meteorites recovered in Antarctica / Keil, Klaus -- Radar sounding of ice sheet inland of Transantarctic Mountains / Drewry, D.J. -- Transantarctic Mountains glacial history-general problems / Mayewski, Paul

The feeding and fat dynamics of resident juvenile Atlantic salmon (Salmo salar L.) during winter

This thesis investigated the relationships between the feeding behaviour and use of stored fat in overwintering Atlantic salmon parr remaining destined to remain resident in freshwater the following year. Experiments investigated the responses to periods of food shortage at different times of the year to assess the influence of season. Investigations were carried out to examine how feeding motivation and fat storage were influenced by changes in those environmental cues that indicate the change of season. The effect of the normal winter behavioural pattern upon feeding and fat was also investigated

All change at the water's edge: invasion by non-native riparian plants negatively impacts terrestrial invertebrates

Riparian zones are complex, dynamic habitats that play a critical role in river ecosystem functioning. Terrestrial invertebrates comprise much of the diversity found in riparian habitats and facilitate the transfer of energy between aquatic and terrestrial systems. However, the consequences for terrestrial invertebrates of invasion of riparian zones by invasive non-native plants (INNP) remain poorly understood. Responses of terrestrial macroinvertebrate morphospecies to invasion by two common INNP, Fallopia japonica (Japanese knotweed) and Impatiens glandulifera (Himalayan balsam) were assessed, relative to local environmental factors. Terrestrial invertebrates were collected from 20 sites on low order streams in June and August alongside data on physical attributes and land use. Greater cover of F. japonica and I. glandulifera cover reduced total invertebrate abundance and morphospecies diversity at the individual sample scale, whilst increasing spatial heterogeneity of invertebrates at the site scale. Impatiens glandulifera reduced morphospecies diversity at the site scale with increasing cover, but this was not observed for F. japonica. INNP affected terrestrial invertebrate morphospecies abundance and diversity, to a greater extent than prevailing environmental conditions. Our findings therefore offer support for managing riparian plant invasions to improve habitat heterogeneity, restore terrestrial invertebrate diversity and repair aquatic-terrestrial linkages

Stream invertebrate diversity reduces with invasion of river banks by non-native plants

1. Invasion of riparian zones by non-native plants is a global issue and commonly perceived as a challenge for river and fishery managers, but the type and extent of ecological changes induced by such invasions remain poorly understood. Established effects on sediment delivery, allochthonous inputs and channel shading could potentially alter aquatic macroinvertebrate assemblages, with implications for in-stream ecological quality. 2. We assessed responses in the diversity, quality and heterogeneity of stream macroinvertebrate communities to riparian invasion by non-native plants. Macroinvertebrates were collected from 24 sites on low order streams in central and southern Scotland during spring and autumn. The effect of invasive non-native plants (INNP) on macroinvertebrates was assessed relative to that of local physical and chemical factors. 3. INNP cover was associated with stronger effects than other factors on local diversity of macroinvertebrates (33% reduction at the highest INNP cover) but also increased macroinvertebrate abundance across sites. Invaded sites were also associated with lower macroinvertebrate biomonitoring scores. Community composition differed between invaded and uninvaded sites in autumn, but not in spring. However, INNP influence on macroinvertebrate composition was generally secondary to that of physicochemical variables (e.g. channel shade, substrate diversity). 4. We demonstrate that the influence of INNP extends beyond well-known impacts on plant communities to reductions mainly in stream macroinvertebrate diversity. Combined with the negative impact on pollution-sensitive macroinvertebrate taxa this raises concerns over the ecological health of streams with heavily invaded riparian zones. Our findings suggest that efforts to improve low order streams by actively managing severe riparian invasions are merited, but the size and uncertainty of the likely ecological gains must also be evaluated against the effort involved

The social influence scale for midwifery: factor structure and clinical research applications

The role of perceived authority on the clinical behaviour and decision-making of midwives has received little research attention, largely due to the unavailability of a midwifery-specific measure of conformity. The current study investigated the factor structure of the social influence scale for midwifery (SIS-M), a recently developed measure of conformity designed specifically for use within midwifery practice. Confirmatory factor analysis revealed that a four-factor model of conformity, comprising distinct dimensions of conformity, client control, personal control and non-conformity offered an excellent fit to the data. It is concluded that, though the SIS-M was developed as a unitary measure of conformity, there is also compelling evidence that the SIS-M could be developed as a multi-dimensional measure of distinct, but related, conformity dimensions. The SIS-M therefore offers considerable potential as a research tool to gain novel insights into the conformity behaviour of midwives in the practice environment and the relationship of such behaviour to maternal and neonatal outcomes