bluuebunny/crossref_metadata_2025 huggingface dataset:
Análisis de la distribución geográfica de los anomuros (Crustacea: Decapoda) del Golfo de California, México
Authors: CORREA‐SANDOVAL FRANCISCO , RODRÍGUEZ‐CORTÉS DIANA ESMERALDA
Published: March 2003

The anomuran crabs are important from the biogeographic perspective because of their benthonic behavior in their adult state. For this reason, the present work summarizes the different studies developed to date on these crustaceans within the Gulf of California and reinforces the separation of the zone from others in the Province of Cortéz, or Cortesiana. The Gulf of California is inhibited by seventy‐eight species of anomurans, belonging to seven families and twenty‐eight genera. The best represented family regarding the number of genera (eleven), species (forty‐five) and endemic species (eleven) is the Porcellanidae, followed by the Diogenidae with eight genera, fifteen species and four endemic species. The Gulf of California species are distributed in three large zoogeographical groups in the Eastern Pacific, the main one being the Panamic with an intrusion to the Gulf of 69.23% of the species reported. A second important group is that of the endemic species of the Gulf, with 24.35% of the existing species. The boreal species group with intrusion to the Gulf is present with 6.41%. Within the Californian Gulf, ten different zoogeographical groups are found, which demonstrate the great complexity of anomuran distribution, a product of the evolutionary history of this interior sea.
The occurrence and abundance of plants with extrafloral nectaries, the basis for antiherbivore defensive mutualisms, along a latitudinal gradient in east Asia
Authors: Pemberton Robert W.
Published: March 2003

Abstract. The occurrence and abundance of indigenous plants with extrafloral nectaries was evaluated within local communities and regional floras along a north to south gradient from tundra in northeastern Russia (64–70°N) through temperate types in eastern Russia and Korea to subtropical vegetation in the Bonin Islands (26–27°N) south of Japan. Moving from tundra to subtropical vegetation, there is a pattern of increasing abundance of extrafloral bearing plants as a function of total plant cover (from 10.25 to 40.18%), number of species per sampled area (from 0.11 to 1.13/100 m), and proportion of species within regional floras (from 0.32 to 7.46%). There were some plants with extrafloral nectaries in all communities but their abundance varied greatly, c. 1–25% in the four northern latitudes and c. 7–70% in the subtropical region. Ants, the primary mutualists associated with plants bearing extrafloral nectaries, have a similar pattern of increasing abundance (species richness, nest density, and colony size) along the same north–south latitudinal gradient.
Interannual variability of NDVI and its relationship to climate for North American shrublands and grasslands
Authors: Paruelo José M. , Lauenroth William K.
Published: March 2003

Abstract. Our objective was to analyse the interannual variability of different characteristics of the seasonal dynamics of NDVI and their relationships with climatic variables for grassland and shrubland sites of North America. We selected twenty‐five sites located in relatively undisturbed areas. We analysed the variability of seven traits derived from the annual dynamics of the NDVI at each site: the annual integral, the difference between maximum and minimum NDVI, the dates of the inflection points of a double logistic model fitted to the NDVI curve, the difference between these dates, the date of maximum NDVI, and the coefficient of determination of the double logistic model.

The temporal variability of traits that integrated aspects of primary productivity over the year was lower than those related to seasonality. This suggests that from year to year, grassland and shrubland ecosystems would differ more in the timing of production and senescence than in the total amount of carbon fixed. The integral of NDVI showed less temporal variability than annual precipitation. The coefficient of variation of both precipitation and the NDVI integral were positively related. The slope of the relationship was significantly lower than 1, indicating that the variability of ecosystem function is a lower proportion of the variability of annual precipitation in areas with a high relative variability of this climatic variable than in areas of low variability. The variability of most of the NDVI traits analysed showed a negative and, in general, non‐linear relationship with annual precipitation. The same kind of relationship has been reported elsewhere for annual precipitation and its coefficient of variation. Mean annual precipitation has been reported as the main control of above‐ground net primary production in grassland and shrubland ecosystems. Our results suggest that this climatic variable is also associated with the interannual variability of carbon gains, such as the primary production and its seasonality.
Environmental correlates of species richness for native freshwater fish in Oregon, U.S.A.
Authors: Rathert D. , White D. , Sifneos J. C. , Hughes R. M.
Published: March 2003

Aim To better understand how environmental factors affect fish species richness across the state of Oregon.

Location Oregon, U.S.A.

Methods A database showing collection locations of 4911 fish specimens in the Oregon State University museum was modified by the Oregon Natural Heritage Program to include probable occurrences, and mapped within a grid of 375 hexagons that cover the state. The individual species maps of freshwater fish in Oregon were reviewed and revised by thirty regional fish biologists and then synthesized into a single map of native species richness. We used regression tree analysis (RTA) and multiple linear regression (MLR) to assess patterns of fish species richness with twenty environmental, three anthropogenic, and two historical variables.

Results RTA explained 66% of the variation in native species richness, associating richness with annual air temperature range, minimum January temperature, introduced species richness, and stream density. MLR explained 68% of native species richness variation and associated richness with maximum July temperature, air temperature range, standard deviation of monthly temperature, stream density, introduced species richness, and basin connectivity.

Main conclusions We conclude that for these data and at this scale, native fish species richness in Oregon is associated with annual climatic extremes, spatial variability of climate, stream density, basin connectivity, and introduced fishes.
Woodland biodiversity, palaeo‐human ecology and some implications for conservation management
Authors: Tipping Richard , Buchanan James , Davies Althea , Tisdall Eileen
Published: March 2003

This paper appraises the role of prehistoric human societies in modifying the natural woodland biodiversity of several regions throughout Scotland. It draws attention to the likelihood that, contrary to popular belief, biodiversity was enhanced by interactions between agricultural communities and woodlands. The possible purposefulness of such interactions is discussed.

Mindful of the present concern to re‐establish ‘native’ woodlands in many parts of northern Britain, we then review three approaches to the identification of native tree types in Scotland, and conclude that insufficient attention in reafforestation schemes is being paid to (a) the palaeoecological record as a record of native woodland or (b) the likely former high taxonomic diversity of woodlands. Both these failings will lead to the creation of new woodlands lacking in species diversity.
Plant survival in Iceland during periods of glaciation?
Authors: Rundgren Mats , Ingólfsson Ólafur
Published: March 2003

AimThe paper addresses the classical question of possible plant survival in Iceland during the last glacial period in the light of a palaeobotanical record from northern Iceland, spanning the period 11,300–9000BP, including the Younger Dryas stadial. We review the Late Cenozoic fossil plant record, the past debate on glacial plant refugia in Iceland, and the evidence for ice‐free areas during the Weichselian.

LocationThe investigated lake sediment record comes from Lake Torfadalsvatn, which is situated in the northwestern part of the Skagi peninsula in northern Iceland.

MethodsThe sediment chronology was constructed from the cccurrence of the Vedde Ash and the Saksunarvatn ash, two well‐dated Icelandic tephras, together with the results from five AMS and conventional radiocarbon dates performed on bulk sediment samples. The vegetational reconstruction was based on detailed pollen analysis of the sediment sequence.

ResultsThe pollen analysis revealed that many of the taxa present in the area prior to the Younger Dryas stadial continued to produce pollen during that cold event. The more or less immediate reappearance of a few other pollen taxa at the Younger Dryas‐Preboreal boundary suggests that these plants also survived, even if they did not produce sufficient pollen to be recorded during the Younger Dryas stadial.

Main conclusionsWe conclude that the relatively high plant diversity found in high Arctic areas and present‐day nunataks in Iceland and Greenland, together with the fact that many plant species were able to survive the Younger Dryas stadial on the Skagi peninsula, suggest that species with high tolerance for climate fluctuations also survived the whole Weichselian in Iceland. This conclusion is supported by recent palaeoclimatic data from ice‐cores and deep‐sea sediments, indicating that Icelandic climate during the last glacial was only occasionally slightly colder than during the Younger Dryas stadial.
Distribution patterns of páramo plants in Ecuador
Authors: Sklenář P. , Jørgensen P. M.
Published: March 2003

We will analyse the geographical and vertical distributions of Ecuadorian high páramo plants. Lists of species were prepared for six Ecuadorian mountains, and floristic relationships among them were expressed by means of Sørensen's index of similarity. A mantel test was employed to analyse the pattern of geographical distribution of the species to see if the distance between the mountains was sufficient to explain the differences discovered. Altitudinal range and mean altitude of species occurrence were tested against the number of mountains from which the species were recorded using a Kruskal–Wallis nonparametric test. We found that distance as a single factor can not fully explain the pattern of floristic similarity shared by the mountains. Other important factors are involved. Altitudinal range of the species examined was positively correlated with their distribution in Ecuador. Species with a broad altitudinal occurrence were found on several mountains, whereas species with narrow altitudinal distribution were found on fewer mountains.
Analysis of plant species diversity with respect to island characteristics on the Channel Islands, California
Authors: Moody Aaron
Published: March 2003

Aim

Species richness of native, endemic, and exotic plant groups is examined relative to island area, disturbance history, geological history, and other physical characteristics. Of particular interest are the biogeographic factors that underlie (a) differences in species‐area and species‐isolation relationships between plant groups; and (b) adherence or departure of individual islands and/or plant groups from expected patterns.

Location

The eight Channel Islands lie along the continental margin between the U.S./Mexico border and Point Conception, CA. They range in size from 2.6 to 249 km2, and are located from 20 to 100 km off the coast. The islands are known for their high degree of plant endemism, and they have undergone a long history of human occupation by indigenous peoples, followed by over a century of intensive grazing and other biotic disturbances.

Methods

The study is based on linear regression and residual analysis. Cases where individual islands and/or specific plant groups do not adhere to patterns expected under species‐area and species‐isolation paradigms, are evaluated with respect to other island characteristics that are not captured by considering only island size and isolation.

Results

All three plant groups exhibit strong, positive relationships between species richness and island size. For native species, the variance that remains after consideration of island size is largely explained by island isolation. For exotic species, residuals from the species‐area relationship are unrelated to isolation. For endemic species, residuals from the species‐area relationship are negatively related to isolation. Several islands are outliers for endemic and exotic species, for which richness values are not explained by either island area or isolation.

Main conclusions

Species‐area and species‐isolation relationships for native, endemic, and exotic plant groups differ in accordance with hypothesized differences in the biogeographic factors that govern species diversity for these three groups. Most notably, endemic richness increases with isolation, suggesting the influence of this variable on processes of speciation and relictualism. These general relationships persist despite a long and varied history of human activity on the islands. Analysis of residuals suggests that deviations from expected patterns correspond to island‐specific biogeographic factors. It is hypothesized that primary among these factors are land‐use history, island environmental characteristics, and community‐type richness.
Latitude and latitudinal extent: a global analysis of the Rapoport effect in a tropical mammalian taxon: primates
Authors: Harcourt A. H.
Published: March 2003

Aim

Analyses of the Rapoport effect (species at high latitudes have broader latitudinal ranges) usually indicate only a weak effect in the tropics. However, studies of tropical taxa are rare. This study used a global analysis of a tropical order, primates, to ask two questions. Is there a Rapoport effect in this tropical, terrestrial mammal, globally or per continent? If so, can the effect be explained by greater adaptability of higher latitude taxa.

Location

Globe.

Methods

Geographical data for the majority of primates species are available. Genera, rather than the species, were the main data used because the genus is a more stable taxonomic level for this order. Regressions and Spearman correlations were used to test for the effect. Generic ranges are the sum of the constituent species’ ranges. In addition, phylogenetic effects were controlled for to minimize dependence of data.

Results

The Rapoport effect is apparent globally when Madagascar and outlier taxa are excluded. It is also present separately in Africa, Asia and Madagascar when outlier genera are excluded, but not in South America. The effect persists globally, and in Africa and Asia when phylogeny is controlled for.

Climatic variation (temperature or precipitation) correlates with either mid‐latitude or extent of latitude of genera in Africa, Asia and the Americas (insufficient data for Madagascar), but controlling for phylogeny confirms only the African and Asian correlations. The four measures of adaptability of taxa (number of dietary types, number of habitat types, body mass and number of species per genus) correlated variously with latitudinal extent of the taxa, but the correlations did not always match the existence of a Rapoport effect in the respective continents.

Main conclusions

The intercontinental variation apparent in the Rapoport effect in the tropics should be fruitful material for further study of the causes of the Rapoport effect. The discovery of significant associations of measures of adaptability with latitudinal extent in both the presence and the absence of a Rapoport effect indicates that care is needed in using such associations to explain the Rapoport effect.
Rainfall variability, fire and vegetation dynamics in neotropical montane ecosystems in north‐western Argentina
Authors: Grau Héctor Ricardo , Veblen Thomas T.
Published: March 2003

Aim

We explored the relationships among rainfall, fire and tree population dynamics during the twentieth century. Relationships were analysed on seasonal, interannual and multiannual time scales.

Location

The study was conducted at ecotones between Andean grasslands and montane forests in north‐western Argentina. In this area of subtropical monsoonal climate (wet summers, dry winters), annual rainfall has increased and forests have expanded into grasslands and shrublands during the 20th century.

Methods

We used annual tree‐rings of alder (Alnus acuminata H. B. K.), the dominant tree species, to date fire scars on 265 trees and determine establishment dates of 455 trees dispersed over areas > 100 ha at five sites. We also sampled tree establishment and resprouting in 21 plots of 0.1–5 ha and determined mortality patterns in one recently burnt stand.

Results

Fire occurrence during the winter dry season tends to lag by 1 year after years of above‐average moisture availability. This pattern is probably due to enhanced production of fine fuels during the growing season of the preceding years. Over 5‐year periods, higher fire frequency is associated with greater variability in rainfall. On a 5‐year time scale, tree establishment is also associated with higher rainfall variability. Tree age structures suggest that a decades‐long trend towards increased rainfall may also promote forest expansion. By the age of 10–20 years, Alnus acuminata attains a large enough size to survive the low‐intensity fires typical of these open woodland sites. Recovery of A. acuminata after fire is also assured by vigorous resprouting and seedling establishment after fire removes or reduces the herbaceous understorey. During relatively wet periods or at relatively wet sites, fire appears to favour forest expansion by reducing competition between tree juveniles and non‐forest vegetation.

Main conclusions

These results demonstrate the importance of variability in interannual rainfall as an influence on the dynamics that control ecotones between high Andean grasslands and subtropical montane forest.
Molecular evidence for dispersal rather than vicariance as the origin of flightless insect species on the Chatham Islands, New Zealand
Authors: Trewick Steven A.
Published: March 2003

Aim

The aim was to use mitochondrial DNA sequence data to test between vicariance and oversea dispersal explanations for the origin of the Chatham Islands biota.

Location

New Zealand and the Chatham Islands, separated by c. 800 km in the south‐west Pacific Ocean.

Methods

DNA sequences from the mitochondrial gene cytochrome oxidase I (COI) were obtained from four genera of relatively large and flightless insects (Coleoptera— Geodorcus, Mecodema; Orthoptera—Talitropsis; Blattoidea—Celatoblatta). These were used to test alternative hypotheses for the origin of the Chatham taxa.

Results

Phylogenetic analysis revealed the Chatham taxa in each genus to be monophyletic. Genetic distances exhibited by these genera, between taxa found on the Chatham Islands and mainland New Zealand were relatively low (11.2, 2.8, 3.0 and 4.9%, respectively).

Main conclusions

Even allowing for variation in molecular evolutionary rates, these genetic distances indicate phylogenetic separation of New Zealand and Chatham insect lineages in the Pliocene (2–6 Ma). Such dates are more than one order of magnitude too recent to be explained by vicariant (tectonic) processes. Oversea dispersal from New Zealand to the Chatham Islands is implicated and this conclusion is in keeping with the taxonomy of the endemic avifauna, flora and fossil molluscan fauna.
Geographic distributions of homosporous ferns: does dispersal obscure evidence of vicariance?
Authors: Wolf P. G. , Schneider H. , Ranker T. A.
Published: March 2003

The central problem in biogeography is that interactions between different processes result in the formation of historical patterns, such that it is difficult to discriminate the relative roles of vicariance and dispersal. Ferns are distributed by small wind‐dispersed propagules that are produced in very large numbers and capable of dispersing thousands of kilometers. Thus, most taxon distributions in ferns are assumed to be a function of dispersal rather than vicariance. Here, we review some case examples that provide good evidence for vicariance and dispersal in ferns. We then ask whether dispersal is so extensive in ferns that vicariance is no longer detectable in most cases. Although we think that too few studies have been carried out to make generalizations at this stage, we outline the criteria for an effective research programme that can address this issue. Phylogenetic and distributional data are needed, not only because they are lacking in an evolutionarily important group of organisms, but also because data from ferns and other cryptogams are likely to be crucial in making broad biogeographic statements.
Spatial and temporal variability in seed dynamics of machair sand dune plant communities, the Outer Hebrides, Scotland
Authors: Owen N. W. , Kent M. , Dale M. P.
Published: March 2003

Aim

The subjects of seed banks and seed rain represent comparatively neglected areas of biogeography, yet at the community scale, exhibit interesting patterns in both space and time. This paper describes the seed bank and seed rain characteristics of the machair sand dune communities of the Outer Hebrides. As well as looking at individual species distributions and variability, the seed banks and seed rain are examined in terms of their detailed subcommunity composition and its local spatial and temporal variation. The machair plant (sub)communities show extensive degrees of anthropogenic modification because of past and present agricultural management, including cultivation for cereals over wide areas and for potatoes in large numbers of ‘lazy beds’ or small patches. Thus over the historical period, large areas of machair have undergone regular ploughing and cultivation, which have provided the opportunity for a patchwork of secondary succession to occur. This pattern continues to the present day. Furthermore, most other non‐cultivated plant (sub)communities are intensively grazed, primarily by cattle and also by sheep and rabbits.

Location

South Uist, the Outer Hebrides, north‐west Scotland.

Methods

At two carefully selected locations, a range of these various successional subcommunities have been sampled for their seed banks, by taking cores and for their seed rain, by using specially designed traps located where each seed bank sample was removed. This paired sampling strategy allowed direct comparison of the seed bank and the seed rain. Both individual species distributions and the community assemblages of seed bank/seed rain species are examined in space and time using techniques of numerical classification [two‐way indicator species analysis (TWINSPAN)] and ordination [detrended correspondence analysis (DCA)].

Results and conclusions

There is considerable heterogeneity within and between machair subcommunities in terms of seed bank and seed rain characteristics. The soil seed banks and seed rain of the agriculturally disturbed machair subcommunities are consistently more dense and more species rich than non‐cultivated areas of the machair. Overall, machair seed banks are small and stable with no discernible seasonal trends in either size or species composition. In contrast, seed rain on the machair is characterized by a distinct temporal trend. Both seed banks and seed rain are potentially very poor sources of propagules for recolonization following disturbance, indicating that the majority of revegetation following anthropogenic and/or environmental interference is through vegetative reproduction.
The biogeographic regions reconsidered
Authors: Barry Cox
Published: March 2003

Aim

To evaluate the internal consistency and appropriateness of Takhtajan’s system of world‐wide floral Kingdoms in the light of modern knowledge, and similarly to re‐examine the Wallacean system of mammal biogeographic regions.

Main conclusions

It is suggested that Takhtajan’s Cape and Antarctic floral Kingdoms should be deleted, and their constituent parts allocated to the neighbouring Kingdoms. The mammal biogeographic regions are to be restricted to the continents, as defined by the edges of the continental shelves, and the name ‘Wallacea’ is accepted for the area between the Southeast Asian and Australian continental shelves. Modifications are suggested for the names of some of the floral Kingdoms and mammal biogeographic regions.
Islands as model systems for understanding how species affect ecosystem properties
Authors: Wardle David A.
Published: March 2003

Aim

To evaluate the potential of island systems as tools for investigating how species affect ecosystem properties. This is done by first reviewing the available literature, and then by focusing on a study in an archipelago of lake islands in northern Sweden.

Location

Islands in lakes Uddjaure and Hornavan in the northern Swedish boreal forest.

Results

The available literature suggests that islands offer two types of opportunities for investigating how species affect ecosystem properties. The first emerges from the fact that island biotas are often relatively depauperate compared with corresponding continental biotas. This enables the effects of species to be assessed against a less complicated background. The second involves the use of islands as spatially independent replicate ecosystems, which can be used to evaluate the effects of ecosystem drivers over larger spatial scales than is possible through most other approaches that allow proper replication of ecosystems. Examples are presented of the use of each approach. The Swedish lake island system is based on fifty independent islands. A wildfire frequency gradient across these islands favours different plant functional types on different islands; this leads to plant species effects influencing a range of properties both above‐ and below‐ground. Two examples are presented of ecological issues that can be investigated using this island system. First, the difference in fire frequency across islands enables assessment of the effects of fire (and hence fire suppression) on terrestrial carbon storage, and the global change implications of this. Secondly, the system can be used to address theories about the importance of plant community composition and biodiversity in driving ecosystem properties at the across‐island spatial scale.

Conclusions

Islands provide real opportunities for investigating biological drivers of ecosystem functioning, although they have been vastly underused for such purposes. Further, island studies have significant potential for investigating the effects of global change phenomena on terrestrial ecosystems, ranging from the impacts of biodiversity loss and invasive organisms to issues relating to terrestrial carbon sequestration. Island ecosystems enable questions to be addressed about ecosystems over ecologically meaningful spatial scales that can be addressed in no other way.
The taxonomic status of the `sea trout' from the north Adriatic Sea, as revealed by mitochondrial and nuclear DNA analysis
Authors: Snoj Aleš , Marčeta Bojan , Sušnik Simona , Melkič Enver , Meglič Vladimir , Dovč Peter
Published: March 2003

Aim

Unclassified salmonids, generally named `sea trout', have been spotted on occasion in the north Adriatic Sea, although autochthonous salmonids have not been reported in the Mediterranean Sea. On the basis of their phenotype, these fish were regarded as the rainbow trout or salmon‐like fish. The aim of the study was to determine the taxonomic status of the `sea trout' and its origin.

Location

The specimens originate from the coastal waters of the Gulf of Trieste, northern Adriatic Sea, and from hatchery‐reared stock of brown trout (Salmo trutta), derived from Trentino fish‐farm.

Methods

Meristic measurements, nucleotide identity‐test of mitochondrial DNA (mtDNA) (control region) and polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) analysis of nuclear DNA (lactate dehydrogenase C1* gene) were performed.

Results

Morphological characters of the `sea trout' specimens analysed, correspond best with those used for S. trutta and S. marmoratus. Genetic tests denoted explicit similarity between the `sea trout' and hatchery‐reared brown trout. Mitochondrial DNA analysis of the `sea trout' revealed 100% nucleotide identity with brown trout of the Atlantic phylogeographical lineage. Results inferred from nuclear DNA analysis, confirmed the Atlantic descent of the `sea trout' and demonstrated also a certain level of introgression with the brown trout of Danubian lineage.

Main conclusions

Using mtDNA and nuclear DNA analysis it was concluded, that the Adriatic `sea trout' belong to species S. trutta and is most likely derived from hatchery‐reared brown trout population.
Avian response to removal of a forest dominant: consequences of hemlock woolly adelgid infestations
Authors: Tingley Morgan W. , Orwig David A. , Field Rebecca , Motzkin Glenn
Published: March 2003

Abstract Aim  This study examines changes in avian community composition associated with the decline and loss of eastern hemlock [Tsuga canadensis (L.) Carr.] resulting from chronic hemlock woolly adelgid (HWA; Adelges tsugae Annand) infestations.

Location  The study was conducted in a 4900‐km2 study region extending from Long Island Sound northward to the southern border of Massachusetts and including the Connecticut River Valley in Connecticut, USA.

Methods  Bird surveys were conducted at 40 points in 12 hemlock stands varying in HWA infestation and overstory mortality levels during the avian breeding seasons of 2000 and 2001. Ten‐minute, 50‐m radius point counts were used to survey all birds seen or heard at each point. Overstory and understory vegetation were sampled at each point. Indicator species analysis and non‐metric multidimensional scaling were used to examine relationships between avian community composition and vegetation structure.

Results  Overstory hemlock mortality was highly correlated with avian community composition. Abundance of eastern wood‐pewee (Contopus virens), brown‐headed cowbird (Molothrus ater), tufted titmouse (Baeolophus bicolor), white‐breasted nuthatch (Sitta carolinensis), red‐eyed vireo (Vireo olivaceus), hooded warbler (Wilsonia citrina), and several woodpecker species was highest at points with >60% mortality. Black‐throated green warbler (Dendroica virens), Acadian flycatcher (Empidonax virescens), blackburnian warbler (Dendroica fusca), and hermit thrush (Catharus guttatus) were strongly associated with intact hemlock stands that exhibit little or no mortality from HWA.

Conclusions  Eastern hemlock has unique structural characteristics that provide important habitat for numerous bird species in the north‐eastern US. As a result, removal of hemlock by HWA has profound effects on avian communities. Black‐throated green warbler, blackburnian warbler, and Acadian flycatcher are very strongly associated with hemlock forests in southern New England and appear to be particularly sensitive to hemlock removal. The hooded warbler, a species whose status is of regional concern, may actually benefit from the development of a dense hardwood seedling layer associated with high hemlock mortality.
How big is a drop? A volumetric assay of essential oils
Authors: OLLEVEANT  , HUMPHRIS  , ROE
Published: March 2003

• There has been an increase in the use of aromatherapy in nursing, and many issues are now being raised which need addressing in order to maintain professional credibility and safe practice.

• These issues include: who can safely practise aromatherapy, what qualifications are required to practise, who provides indemnity, and other issues, including the safety and toxicity of essential oils.

• A small study was undertaken to examine the differences in drop size of bergamot essential oil.

• Drop size was determined by weighing different manufacturers' essential oil of bergamot and it was found that drop size did differ, resulting in unequal doses of essential oil.

• It is important to be aware of this, because there are implications for the size of the dose administered in an aromatherapy treatment.

• This paper raises the issue of standardizing the measurement of essential oils, to ensure that there are no problems regarding safety in their administration.
An exploration of the potential benefits of pet‐facilitated therapy
Authors: BRODIE SARAH J. , BILEY FRANCIS C.
Published: March 2003

• There is mounting evidence to suggest that those who keep pets are likely to benefit from various improvements in health.

• Despite founders of nursing such as Florence Nightingale advocating the importance of animals within the care environment, their integration into hospitals and other health care settings has been slow.

• The literature on animal‐induced health benefits is reviewed and the conclusion is drawn that the potential benefits of pet therapy are considerable.

• It is suggested that nurses can assume an active role in advocating ward pet or pet‐visiting schemes.
The experiences and views of parents who care for ventilator‐dependent children
Authors: NOYES JANE , HARTMANN HANS , SAMUELS MARTIN , SOUTHALL DAVID
Published: March 2003

• Discussion in this paper is drawn from the literature examining the management of children with long‐term assisted ventilation, and a study of parents' experiences and views of caring for their ventilator‐dependent child at home.

• Difficulties in undertaking research into this group of children are highlighted.

• Recommendations are proposed regarding future multidisciplinary, multiagency service development in order to meet the needs of ventilator‐dependent children and their families.
Attitudes of Registered Nurses towards patients with severe dementia
Authors: NORMANN  , ASPLUND  , NORBERG
Published: March 2003

• Meeting the needs and wishes of people with severe dementia is difficult and demanding for carers, and a number of approaches can be used in encounters with dementia sufferers.

• The aim of this study was to explore how registered nurses in a northern Norwegian county thought about approaching people with severe dementia.

• A patient case was used as a vignette, followed by a questionnaire with 13 sets of statements, each set containing two alternative approaches (one reality orientation approach and one personhood focused approach).

• In 12 out of the 13 sets of statements the reality orientation alternative was usually chosen, but responses to the statement regarding the meaning of confusion tended more towards the personhood focused approach.

• RNs with more than the basic education and staff nurses working in a team nursing system, chose the personhood focused approach significantly more often than RNs with no post‐basic education and nurses working in a primary nursing system.

• The article discusses how reflection on daily experiences can improve one's ability to reflect on one's own experiences and encourage a personhood focused approach.

• Working in a team means gaining opportunities to reflect together with coworkers, while working in a primary nursing care system might afford fewer such opportunities.
Mental health training needs of primary health care nurses
Authors: Secker Jenny , Pidd Frankie , Parham Alan
Published: March 2003

• The primary health care team (PHCT) has a critical role to play in the care of people with mental health problems. However, little attention has been paid to the mental health training and preparation required by primary health care nurses.

• This paper reports on a training needs assessment undertaken in one London health authority area.

• The findings indicate that primary health care nurses are undertaking a wide range and increasing volume of mental health work with little preparation and training.

• Specific training needs include time and space to identify training gaps; basic training in mental health, safe working practices and management of role boundaries; and multidisciplinary training.

• In addition, NHS trusts, primary care groups and health authorities need to clarify which aspects of nurses’ mental health workloads are appropriate to their role and develop policies, procedures and training to support them in undertaking that role.
The Clinical Nurse Specialist: perceptions of practising CNSs of their role and development needs
Authors: Bamford Olly , Gibson Faith
Published: March 2003

• This study was carried out to determine the role and development needs of Clinical Nurse Specialists (CNSs) in two acute hospital trusts.

• One of the aims was to obtain a detailed understanding of the current professional experience of Clinical Nurse Specialists.

• Data were collected using focus groups and analysed descriptively.

• Analysis of the content was qualitative, based on a grounded theory approach, and followed the initial steps of open and axial coding.

• Role transition and development needs are identified on a continuum of novice to expert.
Routine intra‐operative assessment of pain and/or depth of anaesthesia by nurse anaesthetists in clinical practice
Authors: Stomberg Margareta Warrén , Sjöström Björn , Haljamäe Hengo
Published: March 2003

• Patient safety and comfort during general anaesthesia and surgery are to a considerable extent dependent on the capability of anaesthesia personnel to interpret directly monitored as well as indirect clinical signs of pain and/or depth of anaesthesia.

• The aim of the present study was to evaluate how nurse anaesthetists in their clinical routine work assess and interpret intra‐operative responses evoked by pain stimuli and/or insufficient depth of anaesthesia.

• A questionnaire was designed to assess the perceived relevance and validity of cardiovascular, respiratory, mucocutaneous, eye‐associated, and muscular responses for routine assessment of intra‐operative pain and/or insufficient depth of anaesthesia in patients undergoing surgery under general anaesthesia.

• Data were obtained from 223 nurse anaesthetists working at nine different university anaesthesia departments in Sweden.

• A number of significant indicators for pain and depth of anaesthesia could be identified for spontaneously breathing as well as for mechanically ventilated patients. No variable was considered entirely specific for either intra‐operative pain or depth of anaesthesia. Changes in breathing rate/volume, central haemodynamics (BP, HR), lacrimation, and presence of moist and sticky skin were given higher score values as indicators of pain than as indicators of depth of anaesthesia. Occurrence of grimaces, attempted movements, and presence of non‐centred pupils were variables considered more indicative of insufficient depth of anaesthesia than intra‐operative pain.

• In conclusion, it is obvious from the present data that indirect physiological signs of intra‐operative pain and depth of anaesthesia are still considered of importance by Swedish anaesthesia nurses in the anaesthetic management of surgical patients.
Life situation of patients with an implantable cardioverter defibrillator: a descriptive longitudinal study
Authors: Flemme Inger , Bolse Kärstin , Ivarsson Anita , Jinhage Britt‐Marie , Sandstedt Bengt , Edvardsson Nils , Fridlund Bengt
Published: March 2003

• The aim of this study was to describe changes in the life situation of patients with an implantable cardioverter defibrillator over a period of 1 year. A sample of 56 consecutive patients took part in the study.

• Life situation was measured through uncertainty in illness, satisfaction, and fear of the life situation. Descriptive statistics were used to present results, and analytical statistics were used to map out changes over time.

• Overall uncertainty showed a decrease over time. A statistically significant difference was found within the domain uncertainty related to information (P < 0.001).

• Satisfaction increased within the domains health‐functioning, socio‐economic, psychological–spiritual, and family.

• The ability to act within the domain health‐functioning showed a statistical significance (P < 0.05).

• The domain life changes within fear in the life situation decreased and showed a statistical significance (P < 0.05).

• The overall life situation showed increased satisfaction as well as lower uncertainty and fear in the life situation.

• The research indicates that patients need more information about changes in the life situation after the implantable cardioverter defibrillator‐implantation. The study encourages more humanistic, holistic research about patients’ life situations as well as more education in teaching skills for health care personnel.
Individually adjusted meals for older people with protein‐energy malnutrition: a single‐case study
Authors: Christensson Lennart , Ek Anna‐Christina , Unosson Mitra
Published: March 2003

• The objective of this study was to investigate the effect of a 3‐month intervention programme consisting of meals based on individual nutritional requirements in residents assessed as protein‐energy malnourished on admission to a municipal care Institution.

• Using a single‐case design, 11 malnourished residents were given individual care aimed at fulfilling their personal requirements for energy intake during a period of 12 weeks. The residents were selected from a sample of 261 newly admitted older adults of whom 87 were assessed to be malnourished on admission. Nutritional status, including anthropometric and biochemical variables and functional capacities were assessed before, during, and after the intervention. Energy intake was recorded every day. Body weight, and serum concentration of albumin and transthyretin were measured every other week.

• During a 3‐month period, the mean value of energy intake reached the calculated energy requirement in 10 residents. Eight residents increased in weight, triceps skin‐fold thickness, and transthyretin concentration. Nine residents increased in arm muscle circumference, and 10 showed increased serum albumin concentration and functional capacity.

• We conclude that nursing care based on individual nutritional requirements, resources, and desires improves nutritional status and functional capacity in a group of malnourished residents.
Spiritual needs as defined by Swedish nursing staff
Authors: STRANG SUSAN , STRANG PETER , TERNESTEDT BRITT‐MARIE
Published: March 2003

• A study was undertaken to describe how Swedish nursing staff at six different units characterize spiritual needs in a broad context, including both religious and existential issues. Another aim was to study whether there are any special groups of patients for whom these needs are considered to be of utmost importance.

• A questionnaire comprising two open‐ended questions (the focus of the study) and six background questions was mailed to 191 nurses. Data were obtained from 141 nurses who worked on the oncology, palliative, neurological, neurosurgery and psychiatric units or in nursing homes.

• Data from the open‐ended questions were analysed using content analysis and classified into three categories: (i) (general) spiritual issues, (ii) religious issues, and (iii) existential issues. Sub‐categories of the latter were (a) meaning, (b) freedom, (c) isolation and (d) death, i.e. the four central issues in existentialism as previously defined by existential philosophers.

• A majority of the nurses only had limited theoretical knowledge about definitions. Nevertheless, their suggestions for improved spiritual and existential support contained essential elements that could be allocated to the three main categories. They had some difficulty distinguishing between spiritual and psychosocial care. According to the nurses, special groups of interest for spiritual and existential support were severely ill, dying persons and immigrants who actively practised their religion.

• We conclude that there is a willingness to pay attention to spiritual and existential needs, but nurses still have difficulty defining what such care should include. The study revealed that nursing staff needed, and also made inquiries about, more education in order to deepen their knowledge.
Mothers' experience of social support following the death of a child
Authors: LAAKSO HILKKA , PAUNONEN‐ILMONEN MARITA
Published: March 2003

• This study aimed at analysing the grief and coping of mothers whose child had died under the age of 7 years. The paper describes the social support received as experienced by mothers.

• Data were collected using a survey (n=91) and interviews (n=50) with mothers who had lost their child at least 1 year previously. The questionnaire contained questions concerning background characteristics, the Hogan Grief Reaction Checklist and open‐ended questions. Survey data were analysed using a two‐way analysis of variance, Wilcoxon test, cross‐tabulation and content analysis. Interview data were analysed using inductive content analysis.

• Findings showed that the spouse, children, grandparents, next of kin, friends and colleagues were the main sources of support.

• Support consisted of emotional support, informational and instrumental support, and consolation and caring. Informational support consisted of advice and guidance from the mother's own mother or fellow sufferers. Instrumental support consisted of assistance with practical issues. Negative support manifested itself in unwarranted interference by relatives in the family's affairs or breaking up of friendships.

• Mothers expected professional practitioners to provide honest information about the dying child's illness and practical arrangements after the child's death, and to keep up hope as long as the child was alive.

• The care facility was also expected to maintain contact with the family after the child's death.
Communities of practice: an opportunity for interagency working
Authors: LATHLEAN JUDITH , LE MAY ANDRÉE
Published: March 2003

• A particular approach to collaborative interagency working is that of mutliprofessional `communities of practice'.

• Four such groups are described in the context of two action research projects, one relating to primary care and the other to outpatient services for dermatology and ENT.

• The facilitating features, and the challenges and the potential of working in this way, are discussed, both from the point of view of understanding how knowledge is used and valued in such groups and as a useful mechanism for the development of services that span different professional perspectives and involve consumer interests.
A comprehensive definition of infant colic: parents' and nurses' perspectives
Authors: HELSETH SØLVI , BEGNUM SUSANNE
Published: March 2003

• Colic is a term that is often used for crying in infancy. There is no unified definition, the aetiology is disputed and there is no effective method of treatment. Therefore, the crying infant constitutes a problem for parents and for nurses in child health clinics.

• The purpose of the study was to develop a clinically acceptable framework for describing colic.

• The design is exploratory, and data were collected through qualitative in‐depth interviews with nurses and parents of crying babies.

• The infants identified by parents and nurses had periods of crying or fussing for more than 3 hours a day, the crying occurring on more than 3 days in any 1 week and lasting for more than 3 weeks. Three categories of crying emerged (intense crying, non‐specific fussing and crying, feeding‐related crying) that presumably differ in aetiology. An overall definition of colic is proposed that incorporates these categories.

• The proposed definition may function as a diagnostic tool for nurses when they encounter problems of infant crying. The definition provides nurses with clinical criteria that can guide data collection. More specific assessment and categorization of infant crying will be helpful for nurses in addressing problems of colic.