听力与言语-语言病理学

行为科学

医学伦理学

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  • Seasonal changes of fine root density in the Southern Californian chaparral.

    abstract::Fine root extractions from soil cores of a south facing slope in the Southern Californian chaparral were used to study the dynamics of feeder root growth in a summer-dry area. The studies were concentrated on the root systems of Adenostoma fasciculatum, Arctostaphylos glauca, Ceanothus greggii, and Rhus ovata. The tot...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00344991

    authors: Kummerow J,Krause D,Jow W

    更新日期:1978-01-01 00:00:00

  • Seed predation in the legume Crotalaria : II. Correlates of interplant variability in predation intensity.

    abstract::Correlates of individual plant escape from seed predation were investigated for an East African population of the shrub Crotalaria pallida (Papilionaceae) in which seed mortality due to chewing insects is high and varies among neighboring individuals. Several plant properties expected to influence phytophagous insect ...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345167

    authors: Moore LR

    更新日期:1978-01-01 00:00:00

  • Carbon dioxide exchange in Cladina lichens from subarctic and temperate habitats.

    abstract::The survival potential of lichens in a given habitat is determined by the response of CO2 exchange to photosynthetically active radiation (PhAR), thallus temperature, and thallus relative water content (RWC). Therefore morphologically similar lichens from contrasting climatic environments 1) should differ in their CO2...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00366074

    authors: Lechowicz MJ

    更新日期:1978-01-01 00:00:00

  • The temperature-related photosynthetic capacity of plants under desert conditions : III. Ecological significance of the seasonal changes of the photosynthetic response to temperature.

    abstract::As described earlier, the native arido-active perennial Hammada scoparia and the cultivated Prunus armeniaca exhibit characteristic seasonal shifts of their temperature optimum of net photosynthesis (OP) under desert conditions in the Negev. In the present paper the OP values were compared with the actual tissue tempe...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00346243

    authors: Lange OL,Schulze ED,Evenari M,Kappen L,Buschbom U

    更新日期:1978-01-01 00:00:00

  • The probable basis of the relationship between growth rate and winter mortality in the lizard Amphibolurus ornatus (Agamidae).

    abstract::At Bakers Hill, differential winter mortality of juvenile slowgrowing Amphibolurus ornatus is correlated with the incidence of frosts (Bradshaw, 1971). The present study shows that the probability an individual will spend the night in a refuge that is safe from the lethal effect of a frost is directly related to the i...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00349996

    authors: Baverstock PR

    更新日期:1978-01-01 00:00:00

  • Microfungal variations relative to post-fire changes in soil environment.

    abstract::Soils of three Picea mariana-Cladina stellaris woodland sites, aged 2, 104 and 137 years after fire, were sampled at 3 cm intervals to 9 cm depth for soil microfungi. Mortierella, Mucor, Penicillium and Trichoderma were the most frequently isolated genera. The species composition of the microfungi remained much the sa...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00349986

    authors: Lucarotti CJ,Kelsey CT,Auclair AN

    更新日期:1978-01-01 00:00:00

  • A mechanism for resource allocation among sympatric heteromyid rodent species.

    abstract::Laboratory feeding experiments were conducted with Dipodomys ordii and Perognathus flavus in an attempt to discover a mechanism which might result in seed size selection. There was no marked difference in the proportions of four seed types collected whether the rodents foraged in the presence or absence of one another...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00377000

    authors: Hutto RL

    更新日期:1978-01-01 00:00:00

  • Artificial oases in a lacustrine desert.

    abstract::1. Aspects of colonization by freshwater invertebrates on artificial substrata (macrophyte models) placed in the benthos of a eutrophic lake were studied. 2. Colonization was rapid, with equilibrium occuring at about 35 days. The colonization rate curve decreased with time but extinction rate remained constant. 3. Pre...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00344574

    authors: Mason CF

    更新日期:1978-01-01 00:00:00

  • An empirical model for estimating CO2 exchange of Bouteloua gracilis (H.B.K.) Lag. in the shortgrass prairie.

    abstract::An empirical model for predicting net photosynthesis (P N ) and dark respiration (R D ) in the field was developed and tested for Bouteloua gracilis (H.B.K.) Lag., the dominant C4 grass of the North American shortgrass prairie. P N is predicted as a function of soil water potential, canopy air temperature, irradiance,...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00344844

    authors: Detling JK,Parton WJ,Hunt HW

    更新日期:1978-01-01 00:00:00

  • Carbon balance, productivity, and water use of cold-winter desert shrub communities dominated by C3 and C4 species.

    abstract::Common generalizations concerning the ecologic significance of C4 photosynthesis were tested in a study of plant gas exchange, productivity, carbon balance, and water use in monospecific communities of C3 and C4 salt desert shrubs. Contrary to expectations, few of the hypotheses concerning the performance of C4 specie...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345803

    authors: Caldwell MM,White RS,Moore RT,Camp LB

    更新日期:1977-12-01 00:00:00

  • Nitrogen fixation by Cercocarpus ledifolius (Rosaceae) in pioneer habitats.

    abstract::Soil properties of pioneer Pinus flexilis stands with similar topography and climate were investigated. Soils supporting this tree in association with Cercocarpus ledifolius were found to have higher percentages of total nitrogen than soils beneath similar stands lacking Cercocarpus.An excavated Cercocarpus ledifolius...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345566

    authors: Lepper MG,Fleschner M

    更新日期:1977-12-01 00:00:00

  • Call differences and calling site segregation in anuran species from central Amazonian floating meadows.

    abstract::The acoustic behaviour of 15 sympatric and synchronically breeding species of frogs in an area of floating meadows near Manaus (Brazil) was studied for a period of 8 months. The calling positions of each species can be identified with certain physiognomic types of vegetation.Sound analyses were used to compare the mat...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345990

    authors: Hödl W

    更新日期:1977-12-01 00:00:00

  • The resistance of Pteridium aquilinum (L.) Kuhn to insect attack by Trichoplusia ni (Hübn.).

    abstract::Resistance of Pteridium aquilinum to insect attack was studied by incorporating air dried bracken leaf meal and extracts of bracken leaf meal into an artificial diet for Trichoplusia ni (Lepidoptera: Noctuidae). When larvae are reared on diets containing 6% bracken leaf meal, they do not mature past the second instar ...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345534

    authors: Hendrix SD

    更新日期:1977-12-01 00:00:00

  • Variable carbon isotope ratios of Dudleya species growing in natural environments.

    abstract::Measurements are reported of carbon isotope ratios of Dudleya species growing in natural plant communities. Considerable variation in the δ13C values are interpreted as indicating substantial flexibility of the photosynthetic pathways between C3 and CAM. The variability in photosynthetic pathway was in response to gen...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00399763

    authors: Troughton JH,Mooney HA,Berry JA,Verity D

    更新日期:1977-12-01 00:00:00

  • Some factors effecting algal densities in a eutrophic farmland stream.

    abstract::Population dynamics of attached algae in a eutrophic farmland stream (Wellow Brook, England) were correlated through multiple regression analyses with changes in 7 physico-chemical parameters (temperature, light, water velocity, pH, NO3-N, P2O5-P, SiO2-Si). Samples were taken every 2 weeks for 25 consecutive months be...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345700

    authors: Moore JW

    更新日期:1977-09-01 00:00:00

  • The value of clumping to prey : Experiments with a mammalian predator.

    abstract::Southern grasshopper mice (Onychomys torridus) were allowed to junt buried mealworms in a laboratory arena. The prey were arranged in two patterns, one aggregated and one relatively dispersed. Mice captured more prey from the dispersed treatment in the 2 h experiment, a result that can be attributed to both the greate...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF01833636

    authors: Taylor RJ

    更新日期:1977-09-01 00:00:00

  • Ecophysiological investigations on lichens of the Negev desert : V. A model to simulate net photosynthesis and respiration ofRamalina maciformis.

    abstract::Previous publications have reported on investigations of CO2 exchange in the desert lichenRamalina maciformis both in its natural habitat in the Negev and in the laboratory. Utilizing laboratory data, net photosynthesis and dark respiration were expressed as mathematical functions of the most important environmental f...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00751603

    authors: Lange OL,Geiger IL,Schulze E-

    更新日期:1977-09-01 00:00:00

  • Feeding in the rotifer Brachionus calyciflorus : I. Regulatory Mechanisms.

    abstract::Feeding behavior in B. calyciflorus was observed in both constrained and unconfined individuals. There are at least three mechanisms by which the ingestion of suspended particles may be regulated. First, the cirri of the pseudotrochus may be extended, allowing particles to enter the funnel-shaped buccal field, or they...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345247

    authors: Gilbert JJ,Starkweather PL

    更新日期:1977-06-01 00:00:00

  • Population dynamics of the chestnut gall wasp, Dryocosmus kuriphilus Yasumatsu (Hymenoptera: Cynipidae) : V. Estimation of the effect of predation by spiders on the mortality of imaginal wasps based on the precipitin test.

    abstract::During the course of a 10-year investigation on the population dynamics of Dryocosmus kuriphilus, a rapid decrease in the number of individuals was noticed in the adult stage. To detect the role of predation by spiders in causing this high adult mortality, spiders collected from the survey station were tested for thei...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345816

    authors: Nakamura M,Nakamura K

    更新日期:1977-06-01 00:00:00

  • Streuabbau in Laubwäldern : Untersuchungen in kalk- und sauerhumusbuchenwäldern.

    abstract::In the "Solling-Projekt" (IBP) of the "Deutsche Forschungsgemeinschaft" the decomposition of different qualities of leaves in acid soil (Solling) and in lime soil (Göttinger Wald) was studied under various conditions (October 1973-October 1974).Plastic rings were used as litter bags in the following way: on the bottom...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345418

    authors: Herlitzius R,Herlitzius H

    更新日期:1977-06-01 00:00:00

  • Statistical analysis of the lichen vegetation of an avenue in freiburg (South-West Germany), with regard to injurious anthropogenous influences.

    abstract::This paper describes the epiphytic lichen vegetation on maple trees along an 1.1-km avenue leading from the outer suburbs of Freiburg toward the city center. A special aim of this investigation was to examine the variation in the coverage by lichens altogether and by each lichen species as a function of increasing dis...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00346838

    authors: Wirth V,Brinckmann B

    更新日期:1977-03-01 00:00:00

  • Correlation between the feeding time of the pike (Esox lucius) and the dispersion of a school of Leucaspius delineatus.

    abstract::The illumination level at which the pike (Esox lucius) eats most Leucaspius delineatus was compared to that at which the school of Leucaspius disperses.The pike easts Leucaspius predominantly when there is little light (50-75% of its entire prey at less than 1 Lux).The school of Leucaspius gradually disperses at less ...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345687

    authors: Dobler E

    更新日期:1977-03-01 00:00:00

  • The allelopathic potential of Erica scoparia L.

    abstract::The phytochemical action of Erica scoparia L. upon its environment was studied. The toxicity of biogenic heath products on red clover seedlings was demonstrated by biological tests. Ten phenolic hydrosoluble compounds were identified; p-Hydroxybenzoic, vanillic, syringic, caffeic, ferulic, p-coumaric, protocatechuic, ...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00344891

    authors: Ballester A,Albo JM,Vieitez E

    更新日期:1977-03-01 00:00:00

  • Frerea indica, a stem succulent CAM plant with deciduous C3 leaves.

    abstract::During the winter in greenhouse culture, Frerea indica(Asclepiadaceae) is a leafless stem succulent resembling the other members of the Stapelieae subfamily. However, in spring it produces leaves which persist during the summer period. CO2 exchange measurements were carried out with Frerea indica at its different seas...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00348709

    authors: Lange OL,Zuber M

    更新日期:1977-01-01 00:00:00

  • Formation and ecological significance of aggregations in collembola : An experimental study.

    abstract::Spatial distribution in the two collembolan species Tomocerus minor and Orchesella cincta is greatly influenced by the distribution of the environmental factors water and food. T. minor is totally restricted in distribution to water-saturated places, where it forms spaced-out aggregations. O. cincta assembles in water...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00346922

    authors: Verhoef HA,Nagelkerke CJ

    更新日期:1977-01-01 00:00:00

  • A climate room for precise regulation of temperature and humidity in connection with a temperature-regulated nest site for wood ants.

    abstract::A climate room is described for precise regulation of temperature and humidity. Humidity is regulated by regulation of the dew-point temperature of the air. The ranges for both dew-point and air temperature are from 2°C to 45°C. The precision of regulation for the temperature is ±0.05°C, for the dew-point temperature ...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00381139

    authors: Bruin MK,Brandt DC,Körner FJ

    更新日期:1976-12-01 00:00:00

  • Distributional pattern of water relations and net photosynthesis of Hammada scoparia (Pomel) Iljin in a desert environment.

    abstract::In the Central Negev, the arido-active Hammada scoparia (Chenopodiaceae) is mainly distributed in runnels and loessial plains of the wadis and exists with fewer and smaller individuals on slopes and tops of the neighboring hills. At the end of the dry season, water relations and chloride content of plants from these h...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345961

    authors: Kappen L,Lange OL,Schulze ED,Evenari M,Buschbom U

    更新日期:1976-12-01 00:00:00

  • The natural history of a fugitive prairie plant (Mirabilis hirsuta (Pursh) MacM.).

    abstract::Some perennial fugitive plants that colonize badger disturbances in xeric prairies have a limited dispersal capacity, and consequently propagules are dispersed over a small area. I hypothesized that high density-dependent mortality might occur early in the life history of such species, and thus increased survival migh...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345316

    authors: Platt WJ

    更新日期:1976-12-01 00:00:00

  • Carbon isotope ratios of crassulacean acid metabolism species in relation to climate and phytosociology.

    abstract::The δ 13C, ‰ values of the two principal, widely distributed CAM species in Big Bend National Park, Texas, were examined and related to phytosociologic and macroclimatic parameters. Samples of Agave lecheguilla and Opuntia engelmannii were collected along an elevational gradient covering 1370 m, and δ values for both ...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345607

    authors: Eickmeier WG,Bender MM

    更新日期:1976-12-01 00:00:00

  • Efficiency of energy utilization of the House Sparrow, Passer domesticus.

    abstract::Multiple regression analyses were made of the effect of food composition upon energetic efficiency and existence energy of House Sparrows, Passer domesticus. Protein content of experimental food is the most important of eleven independent variables tested in the prediction of energetic efficiency. Other variables sign...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345102

    authors: Blem CR

    更新日期:1976-09-01 00:00:00

  • Energy flow in four different field populations of Ancylus fluviatilis (Gastropoda-Basommatophora).

    abstract::Four brook-dwelling populations of Ancylus fluviatilis were studied. Data on life-cycle, specimen number, biomass and egg capsule biomass are reported. By means of experimental data on ingestion, assimilation, growth and egg-production, energy balances are calculated for whole populations.Mean annual biomass turned ou...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00344796

    authors: Streit B

    更新日期:1976-09-01 00:00:00

  • The life-cycle of Cyprideis torosa (Crustacea, Ostracoda).

    abstract::The life-cycle of the dominant brackish water ostracod Cyprideis torosa (Jones, 1850) has been studied during 4 years. The species has only one generation anually. Reproduction is fairly similar throughout the years and appears to be tuned in to temperature. The number of adults has one peak every year and can be desc...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345475

    authors: Heip C

    更新日期:1976-09-01 00:00:00

  • Avian community structure along elevational gradients in the northeastern United States.

    abstract::Breeding birds were censused along four elevational gradients in the Adirondack Mountains, New York, and the Green Mountains, Vermont. The bird communities of the four gradients were basically similar in species composition, richness and amplitude patterns. Three measures of species diversity decreased with increasing...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345296

    authors: Able KP,Noon BR

    更新日期:1976-09-01 00:00:00

  • Interpretation of global differences in plant calorific values : The significance of desert and arid woodland vegetation.

    abstract::Calorific values for the vegetative tissues of a group of perennial desert and arid woodland plants ranged from 3,191 to 5,375 calories per gram, oven dry weight. These span the range of comparable values reported earlier for plants in other environments, and reflect variety in adaptations to dry environments. Tissues...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00557851

    authors: Darling MS

    更新日期:1976-06-01 00:00:00

  • The occurrence rate of ants from the Formica rufa-group in various phytosociologic associations.

    abstract::During the inventory of ant heaps of the group Formica rufa, performed in the years 1972-73 in the Wielkopolski National Park near Poznań, it was found that the vegetal cover composition, determining to a large extent phytosociologic associations, is likely not so important to ants as the dominant stand. First of all,...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00368854

    authors: Wiśniewski J

    更新日期:1976-06-01 00:00:00

  • Repopulation of the polychaete fauna of an intertidal habitat following natural defaunation: Species equilibrium.

    abstract::During summer, 1971, a massive outbreak of red tide resulted in defaunation of a previously characterized sandy, intertidal habitat in upper Old Tampa Bay, Tampa, Florida. Repopulation of the polychaete fauna was studied from August, 1971, to July, 1973. A transect composed of 4 stations running from just below mean h...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00344711

    authors: Dauer DM,Simon JL

    更新日期:1976-06-01 00:00:00

  • The periodicity of daily activity and its seasonal changes in free-ranging and captive kangaroo rats.

    abstract::Populations ofDipodomys microps andD. merriami in eastern California (37°11'N. Lat.) are active on the surface throughout the night and during the whole year. These two species, and the males and females within each species, show no significant differences in times of beginning or end of activity. Beginning and end of...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00572754

    authors: Kenagy GJ

    更新日期:1976-06-01 00:00:00

  • Natural food requirements of the large milkweed bug,Oncopeltus fasciatus (Hemiptera: Lygaeidae), and their relation to gregariousness and host plant morphology.

    abstract::The life ofOncopeltus fasciatus centers on the seeds of milkweeds (Asclepiadaceae,Asclepias syriaca in this study). Adults reproduce prolifically on these seeds, but they engage in only half as much copulation and lay only a few eggs when fed milkweed buds and flowers instead. They can not maintain body weight on a di...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00582894

    authors: Ralph CP

    更新日期:1976-06-01 00:00:00

  • Forest size and avian diversity in New Jersey woodlots with some land use implications.

    abstract::The effect of forest size on avian diversity was studied in oak forest patches in rural New Jersey. Number of bird species continued to increase significantly in old oak woods up through 40 ha. This was due to the progressive addition of carnivorous species with increasing minimum forest size requirements. One large w...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00345649

    authors: Forman RT,Galli AE,Leck CF

    更新日期:1976-03-01 00:00:00

  • Distribution and dispersal in populations capable of resource depletion : A field study on Cinnabar moth.

    abstract::Theoretical predictions from a simulation model of insect distributions and dispersal among isolated food plants have been tested with data gathered from 13 Cinnabar moth populations. Agreement with the predictions was good. Egg batch size was equal to or slightly larger than the number which could be supported by the...

    journal_title:Oecologia

    pub_type: 杂志文章

    doi:10.1007/BF00545484

    authors: Myers JH,Campbell BJ

    更新日期:1976-03-01 00:00:00

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