bluuebunny/crossref_metadata_2025_split huggingface dataset:
Theoretical habitat templets, species traits, and species richness: fish in the Upper Rhône River and its floodplain
Authors: PERSAT HENRI , OLIVIER JEAN‐MICHEL , PONT DIDIER 
Published: May 2006

SUMMARY

Recent developments in ecological theory concerned with habitat templets, species assemblages, and life history traits were examined for the riverine fish communities of the Upper Rhône River, France, in the context of spatial–temporal habitat variability. Relationships among species traits, habitat utilization of species, the relationship between species traits and habitat utilization, and trends of species traits and species richness in the spatial–temporal variability of the habitat types were analysed.
Relationships among twelve species traits, and utilization of eight habitats were examined for twenty‐five fish species using correspondence analysis; the relationship between species traits and habitat utilization was investigated by co‐inertia analysis.
Positive relationships among species traits were observed for size, fecundity, and the number of reproductive cycles per individual. However, species were not well differentiated according to the habitat utilization, except for habitats rarely connected with the main channel (i.e. two types of oxbow lakes).
No significant relationship was found between species traits and habitat utilization, nor for either species traits or species richness when examined in the framework of spatial–temporal habitat variability. Only two species traits corresponded (with slight trends) to predictions in a river habitat templet: (i) the number of descendants per reproductive cycle increased along with temporal variability; and (ii) the number of reproductive cycles per individual was either low or high at low temporal variability and intermediate at elevated temporal variability.
The discrepancy between the predictions of the river habitat templet as well as of the patch dynamics concept and the results observed for the fish in the Upper Rhône was explained in terms of scale problems, the evolutionary ecology of the European fish fauna, and the history of the Rhône River.
Theoretical habitat templets, species traits, and species richness: birds in the Upper Rhône River and its floodplain
Authors: BOURNAUD MICHEL 
Published: May 2006

SUMMARY

To test predictions of the river habitat templet and the patch dynamics concept, twenty species traits and the species richness of eighty‐one bird species were examined in the context of the spatial – temporal variability of ninety‐one sites at Jons, a section of the Upper Rhône River, France.
The basic information was obtained either from the literature (for species traits) or by observation, then structured by a fuzzy coding technique, and examined using multivariate analyses.
The relationships between species traits separated three groups of birds: (i) large species that are long lived, have long breeding cycles, and use open sites to feed, breed, and sing (e.g. Podicipidae, Laridae); (ii) medium‐sized species with intermediate longevities and breeding cycles that use less open sites (e.g. Columbidae, Corvidae); and (iii) small species that are short lived, have short breeding cycles, and use closed sites (e.g. Sylviidae).
The distribution of birds in the floodplain habitats of the river was closely related to the spatial–temporal variability of sites.
No trends in species traits were observed along a gradient of spatial–temporal variability of the sites.
Species richness of birds was relatively constant over the gradient of spatial–temporal variability of the ninety‐one sites, but decreased at low spatial and high temporal variability because of human activities and vegetation changes that occurred at these sites.
These observations on species traits and richness were related to the high mobility of birds (which is a scale phenomenon) and the high intercorrelation between parameters used to determine the spatial and temporal variability of the sites (which makes separation of the spatial from the temporal variability impossible).
Theoretical habitat templets, species traits, and species richness: floodplain vegetation in the Upper Rhône River
Authors: PAUTOU GUY , ARENS MARIE‐FRANCOISE 
Published: May 2006

SUMMARY

The floodplain vegetation at approximately 100 sites located in nine different habitat types of the Upper Rhône River, France, was surveyed three times over the past 27 years. Information on species traits of the higher plants comprising the Rhône floodplain vegetation was based on studies conducted between Geneva, Switzerland, and Lyon, France.
These data were structured using a ‘fuzzy coding’ technique and then examined using ordination analyses to investigate: (i) relationships among species traits; (ii) habitat utilization; (iii) the relationship between species traits and habitat utilization; and (iv) trends of species traits and species richness in the framework of spatial–temporal habitat variability to test predictions of the river habitat templet and the patch dynamics concept.
Size, number of descendants per reproductive cycle, number of reproductive cycles per individual, and the regeneration potential of an individual were positively related with each other, whereas the degree of attachment to the soil decreased, and the reproductive period shifted from autumn/late summer towards early summer/spring, as size increased.
The habitat utilization by the higher plants of the floodplain revealed a double lateral gradient: the first was from the banks of the temporary waters to terrestrial flats; the second from aggrading pebble to aggrading silt habitats. These gradients were related to gradients in water saturation, oxygen conditions, nutrient loading, and nutrient retention of the soils.
A significant relationship between species traits and habitat utilization was observed for the floodplain vegetation, i.e. plant communities used particular habitat types with a particular set of species trait modalities (= categories).
Patterns of species trait modalities were significantly related to temporal and spatial habitat variability but only modalities of the trait ‘parental care’ conformed to trends predicted from theory.
No trends were observed when species richness of different habitat types was considered in the framework of spatial–temporal habitat variability.
Although the habitats of the Upper Rhône clearly act as a templet for the species traits of the floodplain vegetation, the lack of agreement between observations and predictions on trends in species traits and richness in terms of habitat variability suggest that important elements of theory should be rejected. However, human‐induced changes in these habitats are too recent when compared with the longer time periods required for floodplain vegetation to respond to such changes.
Seasonal dynamics of crustacean zooplankton, heterotrophic nanoflagellates and bacteria in a shallow, eutrophic lake
Authors: JÜRGENS KLAUS , STOLPE GISELA 
Published: May 2006

SUMMARY1. The seasonal development of crustacean zooplankton, heterotrophic nanoflagellates (HNF) and bacteria was examined in Grosser Binnensee, a shallow, eutrophic lake in northern Germany. The grazing impact of Daphnia on bacteria and nanoflagellates was estimated from field data on population abundances and from clearance rates obtained in laboratory experiments.2. The seasonal succession of zooplankton showed distinct peaks of Daphnia magna, cyclopopid copepods, Bosmina longirostris and Daphnia galeata and D. hynlina. The population dynamics of Dapfinia had the strongest impact on all sestonic components. Daphnia maxima coincided with clearwater phases, and were negatively correlated with particulate organic carbon (POC), HNF and phytoplankton. Bacterial abundance was only slightly affected although daphnids were at times more important as bacterial consumers than HNF, as estimated from measured bacterial clearance rates. Other crustaceans (copepods, Bosmina) were probably of minor importance as grazers of bacteria and nanoplankton.3. HNF abundance varied from 550 ml−1 to more than 30000 ml−1. HNF appeared to be suppressed by daphnids and reached highest densities when copepods dominated the metazooplankton. The variation in HNF abundance was not reflected in the concentration of heterotrophic bacteria, which fluctuated rather irregularly between 5 and 20 ± 106 ml−1. Long filamentous bacteria which were probably resistant to protozoan grazing, however, appeared parallel to the development of HNF. These bacterial cells, although small in number, could comprise more than 30% of the total bacterial biomass.
Stream hydraulics and the distribution of microcrustacea: a role for refugia?
Authors: ROBERTSON ANNE L. , LANCASTER JILL , HILDREW ALAN G. 
Published: May 2006

SUMMARY1. The relationship between microcrustacean abundance and flow habitat in three contrasting reaches of a single stream was examined.2. Three methods of characterizing stream hydraulics (shear stress frequency distributions, Froude numbers and mean reach velocity) showed the same pattern among the three reaches, which were subsequently termed ‘fast’, ‘slow’ and ‘medium’.3. Distributions of epibenthic microcrustacea matched flow characteristics of the three reaches, being most abundant in the slow reach and least abundant in the fast reach. In contrast, densities of three out of four species of interstitial Harpacticoida did not vary significantly with reach, and none of the parameters measured explained much of their between‐patch variation in density. Hydraulic conditions at the substratum surface may not affect the distribution of species with interstitial habits.4. Patterns in the abundance of organic matter (a possible food source) were examined. Measures of organic matter were highly correlated with hydraulic variables, with detritus being most abundant in the slow reach and least in the fast reach. Despite their strong response to reach, local densities of most microcrustacea (including many epibenthic species) did not vary with organic matter. Food for detritivorous microcrustacea may not be limiting in this highly retentive stream.5. There was some evidence to suggest that different numbers of animals were retained in the three reaches during flow disturbances. One reach may function as a ‘flow refugium’. Models illustrating the processes by which lotic organisms may use flow refugia are presented and provide a framework for future empirical and theoretical studies.
Influence of ethanol and ethylene on the seed germination of three nymphaeid water plants
Authors: SMITS A.J.M. , SCHMITZ G.H.W. , VAN DER VELDE G. , VOESENEK L.A.C.J. 
Published: May 2006

SUMMARY1. Under anaerobic conditions cold stratified seeds of Nymphaea alba and Nuphar lutea germinated readily and released ethanol (up to 6–7 mM ethanol g‐1 DW), whereas seeds of Nymphoides peltata did not germinate and hardly any ethanol was released (up to 1.5 mM ethanol g‐1 DW). Ethylene release by seeds of Nymphaea, Nuphar and Nymphoides incubated under hypoxic conditions could not be detected.2. Under aerobic conditions all Nymphaea and Nuphar seeds germinated, but at a lower rate compared with anaerobic incubation. Ethanol release under aerobic conditions was low (1.5–2 mM ethanol g‐1 DW). Under aerobic conditions the seeds of Nymphoides germinated promptly and ethanol release was low (0–0.5 mM ethanol g‐1 DW).3. Germination of Nymphaea and Nuphar seeds in an ethanol solution (350 mM) was generally stimulated compared with that in water, but no significant effect was recorded if seeds had not received a cold treatment or had been stratified for 8 weeks. Germination of Nymphoides seeds was inhibited in the ethanol solution unless they had received a cold treatment of 12 weeks.4. Germination of Nymphaea and Nuphar was stimulated by ethylene (5 νg 1‐1) but germination in moist air was lower than under normal submersed conditions. A stimulating effect of ethylene on the germination of Nymphoides seeds was also evident.5. It is suggested that ethanol and ethylene play an important role in determining niches for germination, contributing to the zonation of these nymphaeids in a water body.
Microcrustacean prey and macroinvertebrate predators in a stream food web
Authors: LANCASTER JILL , ROBERTSON ANNE L. 
Published: May 2006

SUMMARY1. The consumption of microcrustacea by two polyphagous predators, larvae of the caddisfly Plectrocnemia conspersa (Curtis) and the alderfly Sialis fuliginosa Pictet, was investigated in an English stream with a well‐known macro‐ and microinvertebrate fauna. Benthic samples were collected in August, November, December and April, and the gut contents of all individuals of both predators were examined.2. All the microcrustacean groups (Cyclopoida, Harpacticoida, Chydoridae and Ostracoda) were identified in gut contents. Of the ten taxa present in the benthos, all occurred in the diet of P. conspersa; nine were found in S. fuliginosa.3. Ontogenetic shifts in the diets of both predators were found, and microcrustacea were consumed more frequently by small than large instars.4. There was little evidence of selective feeding by P. conspersa, whereas ostracods were over‐represented in the diet of S. fuliginosa, compared with benthic relative densities. The Chydoridae were under‐represented in the diet of both predators.5. The food web of Broadstone Stream is perhaps the most detailed web available for any running water habitat. Increased taxonomic resolution produced marked changes in values of connectance and predator‐prey ratios. Linkage density remained fairly constant at different levels of resolution and were high, indicative of a web of generalist species. Omnivory was pronounced and may be characteristic of donor‐controlled systems where organic detritus is the primary energy base.
Productivities of microbial decomposers during early stages of decomposition of leaves of a freshwater sedge
Authors: NEWELL S. Y. , MORAN M. A. , WICKS R. , HODSON R. E. 
Published: May 2006

SUMMARY1. We examined standing‐senescing, standing‐dead and recently fallen leaf blades of Carex walteriana in fens of the Okefenokee Swamp to determine the nature of the microbial decomposers in the early stages of decomposition, measuring both standing crops and productivities ([3H]leucineprotein method for bacteria, [14C]acetateergosterol for fungi).2. Fungal standing crops (ergosterol) became detectable at the mid‐senescence stage (leaves about half yellow‐brown) and rose to 14–31 mg living‐fungal C g−1 organic mass of the decaying system; bacterial standing crops (direct microscopy) were ± 0.2 mgC g−1 until the fallen‐leaf stage, when they rose to as high as 0.9 mgC g−1.3. Potential microbial specific growth rates were similar between fungi and bacteria, at about 0.03–0.06 day−1, but potential production of fungal mass was 115–512 μgC g−1 organic mass day−1, compared with 0–22 μgC g−1 day−1 for bacteria. Rates of fungal production were about 6‐fold lower on average than previously found for a saltmarsh grass, perhaps because much lower phosphorus concentratiofis in the freshwater fen limit fungal activity.4. There was little change in lignocellulose (LC) percentage of decaying leaves, although net loss of organic mass at the fallen, broken stage was estimated to be 59%, suggesting that LC was lost at rates proportional to those for total organics during decay. Monomers of fungal‐wall polymers (glucosamine and mannose) accumulated 2‐ to 4‐fold during leaf decay. This may indicate that an increase found for proximate (acid‐detergent) lignin could be at least partially due to accumulation of refractory fungal‐wall material, including melanin.5. A common sequence in decaying aquatic grasses is suggested: principally fungal alteration of LC during standing decay, followed by a trend toward bacterial decomposition of the LC after leaves fall and break into particles.
The effects of shoot age on colonization of an emergent macrophyte (Typha latifolia) by macroinvertebrates
Authors: OERTLI BEAT , LACHAVANNE JEAN‐BERNARD 
Published: May 2006

SUMMARY1. The colonization and dynamics of epiphytic aquatic macroinvertebrates are described on first‐year and second‐year shoots of an emergent macrophyte (Typha latifolia) in a Swiss pond. Effects of shoot senescence on composition, richness, density and biomass of the macroinvertebrates are quantified.2. There were two phases of colonization: a short‐term colonization process which corresponded with that usually observed on inert substrates and a longer term colonization process related to the attractiveness of the shoots for the colonizers. In this second process, the older shoots showed a higher attractiveness for most invertebrate taxa.3. Taxa colonized the shoots at different rates. Rapid colonizers included the limpet Ferrissia wautieri and the mayfly Cloeon dipterum. Conversely, Oligochaeta, Chironomidae and Ceratopogonidae were particularly slow colonizers.4. The older shoots supported a higher mean annual richness, abundance and biomass of invertebrates. Compared with younger shoots, the older shoots demonstrated a higher carrying capacity for most invertebrate taxa, as is the case for many other freshwater macrophytes.
Tissue accumulation and the moult cycle in juveniles of the Australian freshwater crayfish Cherax destructor
Authors: MUSGROVE R.J.B. , GEDDES M.C. 
Published: May 2006

SUMMARY1. This paper investigates moult stage and size‐specific changes in whole body composition during growth in juvenile crayfish in order to better describe the nature of growth and energy use.2. Composition is described in terms of moult stage and size‐specific wet, dry and ash‐free dry weight, water, carbon, protein nitrogen, non‐protein nitrogen, ash and energy. Dry weight and ash‐free dry weight (AFDW) peaked in the middle and in the later stages of premoult. Both peaks were about 2–2.3 times postmoult weight. Losses in tissue weight during ecdysis were substantial in the smallest crayfish but declined with size. Water was taken up between late premoult and early postmoult. Tissue accumulation occurred primarily between B and D1.3, with further weight gain largely the result of fluid uptake. Ash increased immediately postmoult with a major peak occurring during intermoult. Mean organic carbon varied between 33 and 35.5% of the body and 49% of the exuvia. Chitin varied between 9 and 17% of body AFDW and made up about 50.5% of the exuvia. Protein content varied between 47 and 62% of body AFDW and about 25% of the exuvia. Carbon, chitin and protein were not affected by moult stage but protein declined with ocular carapace length (OCL) in larger crayfish. Mean caloric content varied between 19 and 22 J mg‐1 AFDW depending on size and moult stage. Caloric content increased with OCL during premoult and early intermoult then declined with size until part of the way through premoult.3. Relationships between protein, chitin and remaining carbon (organic carbon minus chitin) were examined. It is suggested that protein and some carbon are catabolized during the moulting process, possibly to fuel metabolism. Models are presented showing changes in proximate composition over the moult cycle for two sizes of crayfish, and tissue and energy accumulation and loss over a series of moult cycles and sizes from 3.1 mm to 17 mm OCL.
Periodontal disease in a Rubinstein–Taybi syndrome patient: case report
Authors: FREITAS N. M. , IMBRONITO A. V. , LA SCALA C. S. K. , LOTUFO R. F. M. , PUSTIGLIONI F. E. 
Published: May 2006

Summary.  Introduction.  Rubinstein–Taybi syndrome (RTS) is a rare disorder affecting 1 of 300,000 people, characterized by growth, mental and motor retardation, small stature, broad thumbs and toes, characteristic face, high‐arched palate, and recurrent respiratory infections.Case report.  The present report describes the periodontal and immunological status of a 14‐year‐old female patient with RTS. Probing depth, clinical attachment level, bleeding on probing, and radiographic evaluation were performed. Periodontal examination revealed severe attachment loss in incisors and molars and generalized bleeding on probing. Periodontal treatment consisted of scaling and root planing and oral hygiene instructions. Periodontal treatment resulted in resolution of gingival inflammation and pocket depth reductions. The association of periodontal disease and RTS is previously undescribed.Conclusion.  This case report underscores the importance of periodontal clinical diagnosis and the possibility of successful periodontal treatment in RTS patients.
Rhabdomyosarcoma of the mandible in a 6‐year‐old boy
Authors: DAVIDSON L. E. , SOLDANI F. A. , NORTH S. 
Published: May 2006

Summary.  Introduction.  Rhabdomyosarcoma is an aggressive malignant tumour composed of neoplastic mesenchymal cells that infiltrate surrounding tissue structures, making their precise site of origin unclear. Although rare, this is highly aggressive and the most common soft‐tissue neoplasm of the head and neck in children. Regrettably by the time most cases are initially seen, the patients already have large tumours, due to rapid tumour growth and delayed medical consultation.Case Report.  This report describes a 6‐year‐old presenting with just such symptoms of facial swelling and pain but elicitation of further information and findings, including tooth mobility of 3 days duration, led to prompt referral and early treatment of an embryonal rhabdomyosarcoma.Conclusion.  General dental practitioners are frequently presented with a child with a swollen face and pain. Experience would suggest a dental abscess to be the most likely cause with treatment as appropriate. However, all swellings in children, should be thoroughly investigated and reviewed as particularly in this age group, tumour growth is rapid while early diagnosis allows successful treatment with multimodality therapy.
Attitudes about dental care among parents whose children suffer from severe congenital heart disease: a case‐control study
Authors: GRAHN K. , WIKSTRÖM S. , NYMAN L. , RYDBERG A. , STECKSÉN‐BLICKS C. 
Published: May 2006

Summary.  Objectives.  To examine attitudes and experiences of parents whose children have complex congenital heart disease (CHD) with respect to dental health information and advice, dental care, and service and to compare the results with data from an age‐ and gender‐matched control group without any medical problems.Setting.  Faculty of Medicine (Paediatric Cardiology and Paediatric Dentistry), Umeå University, Umeå, Sweden.Sample and method.  Each group comprised parents of 33 children; the children's mean age was 9·4 years. All the cases and the controls resided in the county of Västerbotten, northern Sweden. Data were collected with a questionnaire with 20 joint questions to both groups and four additional questions to the CHD group.Results.  Of the 20 joint questions, significant differences were displayed in the following areas: the professional group that provided the parents with dental health information and advice (P < 0·01), attitudes to reception at the dental clinic, and experience of sedation before operative dental treatment (P < 0·05). Parents to 11 children with CHD who were patients at a specialist clinic for paediatric dentistry scored the reception at the dental clinic as excellent in nine cases and satisfactory in two, compared to excellent (3), satisfactory (11), decent (4), and poor (4) among those who were patients in general dental practice (P < 0·01). No statistically significant differences in educational level or in parental experience of dental health were noted between the two groups (P > 0·05).Conclusion.  Children with CHD in northern Sweden mainly receive their dental health information from a physician or a dentist, and healthy children mainly receive information from a dental hygienist indicating that children with CHD are given priority in the dental care system. Parental attitudes to reception in the dental service differed, and parents of healthy children scored the reception at the dental clinic better than parents of children with CHD. It is suggested that children with severe CHD should receive dental care in clinics for paediatric dentistry, particularly at early ages.