bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modelling the potential effects of climate change on calcareous grasslands in Atlantic Europe
Authors: Duckworth J. C. , Bunce R. G. H. , Malloch A. J. C. 
Published: March 2003

AbstractAim This study aims to assess the sensitivity of calcareous grassland vegetation to climate change and to indicate the most probable direction of change.Location The study area was a region of Britain, Ireland, France and Spain, centred on the Bay of Biscay, which was defined using a land classification based on climatic criteria.Methods Vegetation was sampled in the field, with additional data collected on soils, climate, management and land cover. The vegetation samples were ordinated by detrended correspondence analysis in order to explore the main gradients present and as a basis for modelling changes. Environmental data were summarized by ordination techniques, with the scores generated used to predict the current vegetation score on the first two ordination axes by multiple regression. The model was then manipulated to represent a 2 °C increase in temperature and resulting shifts in the vegetation samples in terms of their species composition assessed.Results There was a good general agreement between the original vegetation ordination axis scores and those predicted by the model, the latter of which were based on environmental data alone. Following a 2 °C increase in temperature, the predicted changes in the ordination space were demonstrated to be subtle, consisting of small shifts towards vegetation associated with warmer conditions, representing distances 100 km or less on the ground.Main conclusions The models are simple but nevertheless provide a useful basis for the investigation of potential vegetation change. The shifts in the ordination space represent more minor changes than those predicted in previous studies. This suggests that the potential for major change is lower when environmental factors such as soil and management are considered in addition to climate. The potential for change is also reduced when vegetation is considered as a whole rather than on an individual species basis, due to both interspecific interactions and interactions with environmental factors acting as constraints.
Biogeography and climatic differentiation of two annual species of Teesdalia R. Br. (Brassicaceae)
Authors: Hoffmann Matthias H. 
Published: March 2003

AbstractAimThe two annual species of Teesdalia R. Br. occupy nearly exclusive ranges. Autecological data on T. nudicaulis (L.) R. Br., taken from the literature, are compared with data obtained from a climatic analysis of the general distributional range of the species. This paper addresses the question of whether the observed autecological characteristics of the species (local scale) are reflected in the data obtained from the climatic analysis (global scale). Furthermore, the marked biogeographical differentiation of the two annual species of Teesdalia R. Br. is investigated.LocationThe genus Teesdalia is naturally distributed in Europe and North Africa.MethodsThe number of occurrences of the species along climatic gradients is calculated. The data are primarily presented in frequency diagrams (FDs) exhibiting the number of occupied grid cells along the climatic gradients. The temperature–precipitation diagrams (TPDs) are derived from the FDs to illustrate the monthly climate spaces of the species. The climate spaces of the species in the course of the year are shown in the climatic mean diagram (CMD). Each type of diagram illustrates distinctive characteristics of the species’ ranges.ResultsAutecological studies of T. nudicaulis show that distinctive thermal and hydric (autumn and spring) conditions are necessary for optimal germination and fruit set. The significance of these two seasons is also reflected in the climatic analysis of the species’ range. Despite their importance, the results of the autecological study are not sufficient to explain the whole range of the species. It seems that additional factors, such as low temperatures, but also higher or lower amounts of precipitation at temperatures similar to those observed locally, may be limiting in other parts of the range. The three types of diagram shed light on factors affecting the geographical differentiation of the two annual species. However, the biology and ecology of T. coronopifolia (J. P. Bergeret) Thell. are not well enough known to trace evolutionary pathways of this biogeographical differentiation.Main conclusionsLocal ecological or biological studies are necessary for a better understanding of the species’ ranges. Results of local studies concerning the influence of climate on the species’ ranges may be tested at a global level using the methodology presented here. The diagrams provide a framework for analyses of geographical differentiations of species and the formulation of locally testable hypotheses for comparative biogeographical studies.
Participation of species with different zoogeographical ranks in the formation of local faunas: a case study
Authors: Vilenkin B. YA. , Chikatunov V. I. 
Published: March 2003

AbstractAimTo find out how common the earlier explored regularity is in numerical relationships among co‐occurring species with various zoogeographical rank.LocationThe distribution of 284 species of Scarabaeoidea beetles in 20 biotic provinces of Israel and the Sinai Peninsula is considered. This Eastern Mediterranean territory is a part of the Levant area.MethodsAll species are allocated to one of three groups with different zoogeographical rank. These are the Levantine endemics (E), Regional (R) and Ubiquitous (U) species. Relationships among the numbers of species of each group were analysed with the use of multiple and ordinary regression. Similarity between faunas of resulting sets of provinces was analysed using the of chi‐square test.ResultsThe numbers of E‐ and R‐species in each province are statistically independent, while the number of U‐species increases linearly with an increase in the E‐ and/or R‐species number. Two linear regressions appear in the coordinates: ln (E + 1) − R. These regressions unify nine and seven provinces, respectively. The faunas of two sets of provinces differed significantly. Two fringe provinces, which were present within the territory considered only by small parts of their respective zoogeographical units, as well as two provinces with heavily destroyed habitats, fall out of the regression lines. The number of E‐species increases in a south–north direction. The area of maximum diversity is assumed to be somewhat north of the Israeli state border. Success of the invading E‐species is discussed from the standpoint of Van Valen's (1973) Red Queen Theory.Main conclusionsSpecies persisting together are not selected by chance. In our case, three zoogeographical ranks correspond to three grades of species’ ranges. Different ranges are assumed to have different species’ fitness. The present faunas have formed in the two sets of provinces in similar but independent ways.
Holocene palaeoenvironments of salt lakes in the Darling Anabranch region, south‐western New South Wales, Australia
Authors: Cupper Matthew L. , Drinnan Andrew N. , Thomas Ian 
Published: March 2003

AbstractAimFossil pollen preserved within small salt lake basins in the Australian interior is used to reconstruct mid‐ to late Holocene vegetation. The study aims to identify the origin of problems such as woodland decline and salinization within present ecosystems.LocationWarrananga and Tooperoopna salt lakes, south‐western New South Wales, Australia.MethodsPollen, carbonized particle and sedimentological analyses of cores taken from salt lakes.ResultsPrior to c. 4500 years ago, the region supported a dense cover of Casuarinaceae woodlands. It is possible that the subhumid zone species Allocasuarina luehmannii comprised some of the Casuarinaceae element. In the late Holocene, A. luehmannii disappeared from the record and chenopodiaceous low shrublands expanded. About 2000 years ago, Callitris representation decreased. Woodland contraction also occurred after European settlement.Main conclusionsIncreasing aridity or greater seasonal variation in the climate during the late Holocene caused a contraction of woodland vegetation. Increased proportions of Chenopodiaceae may indicate soil salinization around the basins. A decrease in Callitris was possibly due to heightened severity or frequency of drought events after 2000 years ago. Decline in woodland pollen in the uppermost samples is explained by the preferential clearing of Callitris glaucophylla, Callitris gracilis and Casuarina pauper for timber and their limited regeneration because of browsing by stock and rabbits.
Biogeography and evolutionary history of Hyperolius species: application of molecular phylogeny
Authors: Wieczorek Ania M. , Drewes Robert C. , Channing Alan 
Published: March 2003

AbstractAimWe propose a phylogeny of selected Hyperolius species (Anura: Hyperoliidae), based on mtDNA sequence data and parsimony analysis. This phylogeny was used to interpret the historical biogeography of the genus in Africa.LocationSamples were collected throughout the distribution of Hyperolius in Africa.MethodsWe compiled distributional maps of all species, summarized historical changes in vegetation and climate in Africa since the late Cretaceous, and used these in combination to identify historical factors that may have contributed to speciation in these frogs. A phylogeny for Hyperolius was derived from mtDNA sequence data and interpreted in terms of climatic and vegetation changes in Africa.Main conclusionsLowland rainforest is proposed to have been the ancestral habitat of Hyperolius. The expansion of savannah and reduction of lowland rainforest were identified as important factors in the differentiation of the more basal species. Finally, the development of the Rift Valley system played an important role in the speciation of derived species with relatively limited distributions.
Towards a more general species–area relationship: diversity on all islands, great and small
Authors: Lomolino  , Weiser  
Published: March 2003

AimTo demonstrate a new and more general model of the species–area relationship that builds on traditional models, but includes the provision that richness may vary independently of island area on relatively small islands (the small island effect).LocationWe analysed species–area patterns for a broad diversity of insular biotas from aquatic and terrestrial archipelagoes.MethodsWe used breakpoint or piecewise regression methods by adding an additional term (the breakpoint transformation) to traditional species–area models. The resultant, more general, species–area model has three readily interpretable, biologically relevant parameters: (1) the upper limit of the small island effect (SIE), (2) an estimate of richness for relatively small islands and (3) the slope of the species–area relationship (in semi‐log or log–log space) for relatively large islands.ResultsThe SIE, albeit of varying magnitude depending on the biotas in question, appeared to be a relatively common feature of the data sets we studied. The upper limit of the SIE tended to be highest for species groups with relatively high resource requirements and low dispersal abilities, and for biotas of more isolated archipelagoes.Main conclusionsThe breakpoint species–area model can be used to test for the significance, and to explore patterns of variation in small island effects, and to estimate slopes of the species–area (semi‐log or log–log) relationship after adjusting for SIE. Moreover, the breakpoint species–area model can be expanded to investigate three fundamentally different realms of the species–area relationship: (1) small islands where species richness varies independent of area, but with idiosyncratic differences among islands and with catastrophic events such as hurricanes, (2) islands beyond the upper limit of SIE where richness varies in a more deterministic and predictable manner with island area and associated, ecological factors and (3) islands large enough to provide the internal geographical isolation (large rivers, mountains and other barriers within islands) necessary forin situspeciation.
Biogeography and ecology of paedomorphosis in Triturus alpestris (Amphibia, Caudata)
Authors: Denoël M. , Duguet R. , Dzukic G. , Kalezic M. , Mazzotti S. 
Published: March 2003

AimPaedomorphosis is an evolutionary change in which larval structures are retained in adult animals. In newts and salamanders, this heterochronic process is widely represented and concerns the retention of gill slits. We want to find out whether ecological and geographical determinants may be associated with paedomorphosis in the Alpine newt Triturus alpestris.LocationEurope.MethodsDetermination of the main characteristics of all known aquatic sites containing paedomorphic Alpine newt individuals.ResultsAlthough metamorphs are common in Europe, paedomorphs are only found at the southern margin of the geographical range of the species: mainly in Italy and in the Balkans. They were recorded in eighty‐seven aquatic sites. No single trend was outlined for the analysed ecological parameters of the aquatic and terrestrial habitats (e.g. altitude, maximum water depth, drying and presence of forest).Main conclusionsContrary to the first models of paedomorphosis, the main traits of aquatic and terrestrial habitat do not explain the occurrence of paedomorphs in natural populations. Although they were found in favourable aquatic habitats surrounded by hostile terrestrial landscapes, they also exist in temporary waters located at proximity of appropriate terrestrial environments. These results support models predicting paedomorphosis in varied environments, but require complementary investigations on the costs and benefits of the alternative ontogenetic pathways. On the other hand, the southern limitation of the heterochronic phenomenon suggests a genetic basis for paedomorphosis in the studied species.
Ecosystem function and species loss – a microcosm study
Authors: Scarff Fiona R. , Bradley J. Stuart 
Published: March 2003

There are too many kinds of organisms to be able to study and manage each, yet the loss of a single species can sometimes unravel an ecosystem. Such `fusewire species'– critical in the same sense that an electrical fuse can cut out a whole circuit – would be a rewarding focus for research and management effort. However, this approach can only be effective if these `fusewires' represent but a small proportion of the number of species in the system.AimTo demonstrate methods for measuring what proportion of the species in a system are critical to ecosystem function.MethodsThe prevalence of fusewire species was measured in manipulative experiments on an aquatic microcosm.ResultsNo single genus deletion caused changes in key characteristics of the system.Main conclusionsComparison of these results with other published studies shows that the proportion of critical fusewire species varies amongst different ecosystems. The oxidation pond microcosms were shown to contain no single species indispensable to system function. They appear to be ill‐suited to a management strategy which focuses on priority eukaryote species. However, a single study provides no evidence that this result is general or even typical of other kinds of ecosystems; it is presented here as an empirical model. Other methods of investigation are available; they are less experimentally rigorous but more practical. These could provide important guidance in planning an approach to management in a particular ecosystem.
Predictors of deforestation in the Brazilian Amazon
Authors: Laurance William F. , Albernaz Ana K. M. , Schroth Götz , Fearnside Philip M. , Bergen Scott , Venticinque Eduardo M. , Da Costa Carlos 
Published: March 2003

Aim and LocationWe assessed the effects of biophysical and anthropogenic predictors on deforestation in Brazilian Amazonia. This region has the world's highest absolute rates of forest destruction and fragmentation.MethodsUsing a GIS, spatial data coverages were developed for deforestation and for three types of potential predictors: (1) human‐demographic factors (rural‐population density, urban‐population size); (2) factors that affect physical accessibility to forests (linear distances to the nearest paved highway, unpaved road and navigable river), and (3) factors that may affect land‐use suitability for human occupation and agriculture (annual rainfall, dry‐season severity, soil fertility, soil waterlogging, soil depth). To reduce the effects of spatial autocorrelation among variables, the basin was subdivided into >1900 quadrats of 50 × 50 km, and a random subset of 120 quadrats was selected that was stratified on deforestation intensity. A robust ordination analysis (non‐metric multidimensional scaling) was then used to identify key orthogonal gradients among the ten original predictor variables.ResultsThe ordination revealed two major environmental gradients in the study area. Axis 1 discriminated among areas with relatively dense human populations and highways, and areas with sparse populations and no highways; whereas axis 2 described a gradient between wet sites having low dry‐season severity, many navigable rivers and few roads, and those with opposite values. A multiple regression analysis revealed that both factors were highly significant predictors, collectively explaining nearly 60% of the total variation in deforestation intensity (F2,117=85.46, P < 0.0001). Simple correlations of the original variables were highly concordant with the multiple regression model and suggested that highway density and rural‐population size were the most important correlates of deforestation.MainconclusionsThese trends suggest that deforestation in the Brazilian Amazon is being largely determined by three proximate factors: human population density, highways and dry‐season severity, all of which increase deforestation. At least at the spatial scale of this analysis, soil fertility and waterlogging had little influence on deforestation activity, and soil depth was only marginally significant. Our findings suggest that current policy initiatives designed to increase immigration and dramatically expand highway and infrastructure networks in the Brazilian Amazon are likely to have important impacts on deforestation activity. Deforestation will be greatest in relatively seasonal, south‐easterly areas of the basin, which are most accessible to major population centres and where large‐scale cattle ranching and slash‐and‐burn farming are most easily implemented.
Biogeographical research on European species of the lichen genusPhysconia
Authors: Otte Volker , Esslinger Theodore L. , Litterski Birgit 
Published: March 2003

AbstractAim The (world) distribution of the European species ofPhysconiaPoelt (Lichenes: Physciaceae) [exceptPh. distorta(With.) J. R. Laundon andPh.americanaEssl.] was investigated. The study was complemented by data on the ecological behaviour of the species.Location The location of the study is the whole world with a local emphasis on Europe.Methods The geographical distribution of the lichen species under consideration was investigated from collection data of herbaria and field studies in a databank. Additional data were taken from existing literature and critically considered. Distribution maps were created with ArcView GIS. The distribution patterns are expressed as three‐dimensional areal formulas, regarding zonal distribution, altitudinal range and oceanity of the species distributions, using the method ofMeuselet al. (1965).Results The distribution patterns of the tenPhysconiataxa considered are represented in detailed maps and expressed as three‐dimensional areal formulas. The ecological behaviour was discussed.Physconia muscigenaandPh. perisidiosaare species of bipolar distribution type, the other species are holarctic types.Physconia detersaandPh. enteroxanthaoccur in both Eurasia and North America, the remaining species (Ph.griseassp.grisea,Ph. griseassp.lilacina,Ph. petraea,Ph. servitii,Ph. subpulverulentaandPh.venusta) are pure Old world taxa with a much more limited distribution.The majority of the EuropeanPhysconiataxa are distributed meridionally to submeridionally and occur preferentially in suboceanic areas.Main conclusions Some of the species under consideration have a wide distribution, nevertheless they show clear affinities to ecological conditions that influence their distribution patterns. A number of species show not only zonal and regional restrictions, but also affinities to the western climatic type. The Mediterranean is the centre of diversity of the genusPhysconiain Europe.
From optimism to pessimism. A case study of a psychiatric patient
Authors: Hellzen Ove , Asplund Kenneth , Gilje Fredricka , Sandman Per‐olof , Norberg Astrid 
Published: March 2003

• This article focuses on the results of a single case study which illuminates an understanding of phases in nursing care for a patient in a psychiatric setting in Sweden.• The focus of this study is a 50‐year‐old man who showed progressive deterioration from increased motor activity to oral, sexual, destructive and aggressive actions.• Data collection using five methods occurred during a 21‐month period. Results of the content analysis processes identified four distinct but non‐discrete phases of the patient's complex condition.• Medical and nursing care was categorized in three approaches: optimistic, strategic and resigned.• The results raise the question of whether there is action that is without any meaning as an expression of the patient's wishes, thoughts and feelings.• It seems clear that the patient in this study felt really angry and in despair. However, during moments of lucidity, he also indicated that he felt this was not an authentic expression of his ‘real’ self. His experience was that of a splintered world.
An investigation into the information obtained by patients undergoing gastroscopy investigations
Authors: Clements  , Melby  
Published: March 2003

• The benefits of informing patients before undergoing surgery or other investigative procedures are clearly demonstrated in the literature.• This study aimed to determine the amount and type of information given to patients before, during and after undergoing gastroscopy investigations.• A survey approach incorporating structured interviews and structured observation was utilized.• There were statistically significant differences between the information acquired by younger and older patients prior to, but not during or after, the procedure.• Nurses appear to be the most important source of information for older patients while the information leaflet was perceived as the most important source of information for younger patients.
Nurses' perceptions of gross self‐neglect amongst older people living in the community
Authors: ADAMS JOHN , JOHNSON JULIA 
Published: March 2003

• Self‐neglect in older people has an established medical literature but receives surprisingly little attention in the nursing literature.• Hospital and community nurses were interviewed using a semistructured questionnaire.• All the nurses were able to identify patients who had shown features of `gross self‐neglect'.• Poor nutrition was a prominent feature: links with the literature are explored.