解剖学和形态学
麻醉学
听力与言语-语言病理学
行为科学
心脏和心血管系统
细胞和组织工程学
临床神经病学
危重症监护医学
牙科,口腔外科和医学
皮肤病学
急诊医学
内分泌学和新陈代谢
肠胃学和肝脏学
老人病学和老年医学
卫生保健科学和服务
血液学
免疫学
传染病
综合和补充性医学
医学伦理学
医学信息学
医学实验室技术
医学,全科和内科
医学,法律
医学,研究和试验
神经系统科学
护理
营养学和饮食学
产科医学和妇科医学
肿瘤学
眼科学
整形外科学
耳鼻喉科学
病理学
儿科学
周围血管疾病
药理学和药剂学
生理学
基本医疗保健
精神病学
公共、环境和职业卫生
放射学,核医学和医学成像
康复学
生殖生物学
呼吸系统
风湿病学
运动科学
外科学
毒理学
热带医学
泌尿学和肾脏学
病毒学
老年医学
健康政策和服务
心理学,临床
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
更新日期:1978-01-01 00:00:00
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
更新日期:1978-01-01 00:00:00
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
更新日期:1978-01-01 00:00:00
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
更新日期:1978-01-01 00:00:00
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
更新日期:1978-01-01 00:00:00
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
更新日期:1978-01-01 00:00:00
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
更新日期:1978-01-01 00:00:00
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
更新日期:1978-01-01 00:00:00
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
更新日期:1978-01-01 00:00:00
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
更新日期:1977-12-01 00:00:00
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
更新日期:1977-12-01 00:00:00
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
更新日期:1977-12-01 00:00:00
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
更新日期:1977-12-01 00:00:00
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
更新日期:1977-12-01 00:00:00
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
更新日期:1977-09-01 00:00:00
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
更新日期:1977-09-01 00:00:00
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
更新日期:1977-09-01 00:00:00
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
更新日期:1977-06-01 00:00:00
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
更新日期:1977-06-01 00:00:00
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
更新日期:1977-06-01 00:00:00
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
更新日期:1977-03-01 00:00:00
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
更新日期:1977-03-01 00:00:00
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
更新日期:1977-03-01 00:00:00
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
更新日期:1977-01-01 00:00:00
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
更新日期:1977-01-01 00:00:00
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
更新日期:1976-12-01 00:00:00
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
更新日期:1976-12-01 00:00:00
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
更新日期:1976-12-01 00:00:00
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
更新日期:1976-12-01 00:00:00
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
更新日期:1976-09-01 00:00:00
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
更新日期:1976-09-01 00:00:00
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
更新日期:1976-09-01 00:00:00
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
更新日期:1976-09-01 00:00:00
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
更新日期:1976-06-01 00:00:00
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
更新日期:1976-06-01 00:00:00
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
更新日期:1976-06-01 00:00:00
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
更新日期:1976-06-01 00:00:00
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
更新日期:1976-06-01 00:00:00
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
更新日期:1976-03-01 00:00:00
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
更新日期:1976-03-01 00:00:00