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::While elaborate carotenoid-based traits in adult birds may have evolved as honest signals of individual quality in the context of sexual selection or other social interactions, the function of carotenoid-based colours in juveniles is less well understood. We investigated the hypothesis that carotenoid-based nestling c...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1812-z
更新日期:2005-04-01 00:00:00
abstract::Inter-specific competition, facilitation and predation influence herbivore assemblages, but no study has experimentally explored the interactions between large ungulates and small rodents. In a fully replicated, landscape scale experiment, we manipulated densities of domestic sheep in mountain pastures in Norway. We t...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1792-z
更新日期:2005-04-01 00:00:00
abstract::We measured the response of dark respiration (R(d)) to temperature and foliage characteristics in the upper canopies of tree species in temperate rainforest communities in New Zealand along a soil chronosequence (six sites from 6 years to 120,000 years). The chronosequence provided a vegetation gradient characterised ...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1803-0
更新日期:2005-03-01 00:00:00
abstract::Mixed infections, where more than one parasite genotype is present in a single host, have been suggested to be an important factor in host-parasite interactions. As the host represents a limited resource, co-infecting parasite genotypes are expected to be under resource competition. Competition will not only modify th...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1771-4
更新日期:2005-03-01 00:00:00
abstract::For organisms with restricted mobility, density dependence may occur on spatial scales much smaller than that of the whole population. Averaging densities over whole populations in such organisms gives a more or less inaccurate description of the real variation in competitive intensity over time and space. The potenti...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1793-y
更新日期:2005-03-01 00:00:00
abstract::Soil nutrient availability directly enhances vegetative growth, flowering, and fruiting in alpine ecosystems. However, the impacts of nutrient addition on pollinator visitation, which could affect seed output indirectly, are unknown. In a nutrient addition experiment, we tested the hypothesis that seed output in the i...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1780-3
更新日期:2005-03-01 00:00:00
abstract::Interspecific interactions of herbivores sharing a host plant may be important in structuring herbivore communities. We investigated host plant-mediated interactions of root (Hylobius transversovittatus) and leaf herbivores (Galerucella calmariensis), released to control purple loosestrife (Lythrum salicaria) in North...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1747-4
更新日期:2005-02-01 00:00:00
abstract::A trade-off between antimicrobial defences and palatability to dispersers may place limits on fruit persistence in nature. The retention times of ripe fruits on 34 wild plant species under natural conditions (unbagged persistence) and when fruits had been bagged with nylon mesh to exclude frugivores (bagged persistenc...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1730-0
更新日期:2005-01-01 00:00:00
abstract::In most animals, siblings from a given reproductive event emerge over a very short period of time. In contrast, many species of birds hatch their young asynchronously over a period of days or weeks, handicapping last-hatched chicks with an age and size disadvantage. Numerous studies have examined the adaptive signific...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1727-8
更新日期:2005-01-01 00:00:00
abstract::In this paper, we test the mid-domain hypothesis as an explanation for observed patterns of flowering diversity in two sub-alpine communities of insect-pollinated plants. Observed species richness patterns showed an early-season increase in richness, a mid-season peak, and a late-season decrease. We show that a "mid-d...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1694-0
更新日期:2005-01-01 00:00:00
abstract::Functional diversity has been identified as a key to understanding ecosystem and community functioning. However, due to the lack of a sound definition its nature and measurement are still poorly understood. In the same way that species diversity can be split into species richness and species evenness, so functional di...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1744-7
更新日期:2005-01-01 00:00:00
abstract::In highly dynamic and unpredictable environments such as the Southern Ocean, species that have evolved behaviors that reduce the effects of intra-specific competition may have a selective advantage. This is particularly true when juveniles face disadvantages when foraging due to morphological or physiological limitati...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1704-2
更新日期:2005-01-01 00:00:00
abstract::Floral visitors vary in their pollination efficiency and their preferences for floral traits. If low-efficiency pollinators decrease the amount of pollen available to higher efficiency visitors, then low-efficiency visitors may actually have negative fitness consequences for the plants that they visit. We used experim...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1677-1
更新日期:2004-12-01 00:00:00
abstract::Many native communities contain exotic plants that pose a major threat to indigenous vegetation and ecosystem functioning. Therefore the enemy release hypothesis (ERH) and biotic resistance hypothesis (BRH) were examined in relation to the invasiveness of the introduced dune grass Ammophila arenaria in South Africa. T...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1662-8
更新日期:2004-11-01 00:00:00
abstract::Diel vertical migration (DVM) of herbivorous zooplankton is a widespread behavioural phenomenon in freshwater ecosystems. So far only little attention has been paid to the impact of DVM on the phytoplankton community in the epilimnion. Some theoretical models predict that algal population growth in the epilimnion shou...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1645-9
更新日期:2004-11-01 00:00:00
abstract::Dormancy is a common way in which organisms survive environmental conditions that would be lethal to the active individual. However, while dormant, individuals forego reproduction. Hence theory suggests an optimal time in which to enter dormancy, depending on risks associated with both remaining active and entering do...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1657-5
更新日期:2004-11-01 00:00:00
abstract::Plant species and functionally related species groups from arid and semi-arid habitats vary in their capacity to take up summer precipitation, acquire nitrogen quickly after summer precipitation, and subsequently respond with ecophysiological changes (e.g. water and nitrogen relations, gas exchange). For species that ...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-003-1403-4
更新日期:2004-10-01 00:00:00
abstract::This paper gives the first reports on aphid effects on rhizosphere organisms as influenced by soil nutrient status and plant development. Barley plants grown in pots fertilized with N but without P (N), with N and P (NP), or not fertilized (0) were sampled in the early growth phase (day 25), 1 week before and 1 week a...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1651-y
更新日期:2004-09-01 00:00:00
abstract::In ant-plant symbioses, the behavior of ant inhabitants affects the nature of the interaction, ranging from mutualism to parasitism. Mutualistic species confer a benefit to the plant, while parasites reap the benefits of the interaction without reciprocating, potentially resulting in a negative impact on the host plan...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1601-8
更新日期:2004-08-01 00:00:00
abstract::Although an increase in competition is a common cost associated with intraspecific crowding, spatial aggregation across food-limited resource patches is a widespread phenomenon in many insect communities. Because intraspecific aggregation of competing insect larvae across, e.show $132#g. fruits, dung, mushrooms etc., ...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1629-9
更新日期:2004-08-01 00:00:00
abstract::Many mechanisms have been proposed to explain broad scale spatial patterns in species richness. In this paper, we evaluate five explanations for geographic gradients in species richness, using South American owls as a model. We compared the explanatory power of contemporary climate, landcover diversity, spatial climat...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1577-4
更新日期:2004-08-01 00:00:00
abstract::A number of studies at large scales have pointed out that abiotic factors and recolonization dynamics appear to be more important than biotic interactions in structuring stream-fish assemblages. In contrast, experimental and field studies at small scales show the importance of competition among stream fishes. However,...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1578-3
更新日期:2004-07-01 00:00:00
abstract::We sought to understand differences in tree response to meteorological drought among species and soil types at two ecotone forests in northern Arizona, the pinyon-juniper woodland/ponderosa pine ecotone, and the higher elevation, wetter, ponderosa pine/mixed conifer ecotone. We used two approaches that provide differe...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1585-4
更新日期:2004-07-01 00:00:00
abstract::Adaptive within-clutch allocation of resources by laying females is an important focus of evolutionary studies. However, the critical assumption of these studies, namely that within-clutch egg-size deviations affect offspring performance, has been properly tested only rarely. In this study, we investigated effects of ...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1568-5
更新日期:2004-06-01 00:00:00
abstract::We examined the effects of intraguild predation (IGP) and interference competition on an endangered dragonfly, Aeshna viridis Eversm. (Odonata: Anisoptera). A. viridis is rare in Europe due to the decrease in suitable habitats harboring the macrophyte Stratiotes aloides L. Stratiotes plants are the principal ovipositi...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1559-6
更新日期:2004-06-01 00:00:00
abstract::The aim of our study was to identify interactions between the decomposition of aboveground litter and rhizosphere activity. The experimental approach combined the placement of labelled litter (delta13C=-37.9 per thousand ) with forest girdling in a 35-year-old Norway spruce stand, resulting in four different treatment...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1540-4
更新日期:2004-05-01 00:00:00
abstract::We tested whether interspecific competition from Aedes albopictus had measurable effects on A. aegypti at the typical numbers of larval mosquitoes found in cemetery vases in south Florida. We also tested whether the effect of interspecific competition from A. albopictus on A. aegypti differed between sites where A. ae...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1532-4
更新日期:2004-05-01 00:00:00
abstract::Fungal feeding soil invertebrates feed on a wide spectrum of fungal species suggesting that mixed diets increase fitness. We investigated relationships between food preferences for seven saprophytic fungal species/forms and fitness parameters (mortality, growth, time to reproduction, reproduction, egg size) in two Col...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1513-7
更新日期:2004-05-01 00:00:00
abstract::Larvae of the sessile marine invertebrate Bugula neritina (Bryozoa) are protected by an effective chemical defense. From the larvae, we isolated three bryostatin-class macrocyclic polyketides, including the novel bryostatin 20, that deterred feeding by a common planktivorous fish that co-occurs with B. neritina. A uni...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1487-5
更新日期:2004-03-01 00:00:00
abstract::Plant resistance and tolerance to herbivores, parasites, pathogens, and abiotic factors may involve two types of costs. First, resistance and tolerance may be costly in terms of plant fitness. Second, resistance and tolerance to multiple enemies may involve ecological trade-offs. Our study species, the stinging nettle...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-004-1488-4
更新日期:2004-03-01 00:00:00
abstract::Seeds dispersed by tropical, arboreal mammals are usually deposited singly and without dung or in clumps of fecal material. After dispersal through defecation by mammals, most seeds are secondarily dispersed by dung beetles or consumed by rodents. These post-dispersal, plant-animal interactions are likely to interact ...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-003-1480-4
更新日期:2004-03-01 00:00:00
abstract::Generalist parasites may disproportionately use certain hosts because of different benefits associated with each host species. I measured the growth rate of the marine snail Trichotropis cancellata, a facultative kleptoparasite that can suspension feed and steal food, on different hosts to determine the relative nutri...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-003-1467-1
更新日期:2004-03-01 00:00:00
abstract::Recent discussions on scaling issues in ecology have emphasized that processes acting at a wide range of spatial and temporal scales influence ecosystems and thus there is no appropriate single scale at which ecological processes should be studied. This may be particularly true for environmental disturbances (e.g. El ...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-003-1452-8
更新日期:2004-02-01 00:00:00
abstract::There is an increasing ecological interest in understanding the gradients in H(2)(18)O enrichment in leaf water (i.e. a Péclet effect), because an appreciation of the significance of the Péclet effect is important for improving our understanding of the mechanistic processes affecting the (18)O composition of leaf wate...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-003-1449-3
更新日期:2004-02-01 00:00:00
abstract::We examined under laboratory conditions the thermopreference of the migratory locust, Locusta migratoria migratorioides, following infection by the entomopathogenic fungus Metarhizium anisopliae var. acridum and its influence on mycosis. Infected locusts raised their body temperature more frequently than healthy consp...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-003-1431-0
更新日期:2004-01-01 00:00:00
abstract::Stable isotope analyses are often used to calculate relative contributions of multiple food sources in an animal's diet. One prerequisite for a precise calculation is the determination of the diet-tissue fractionation factor. Isotopic ratios in animals are not only affected by the composition of the diet, but also by ...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-003-1429-7
更新日期:2004-01-01 00:00:00
abstract::Carbon and nitrogen stable isotopes were used to examine variation in ant use of plant resources in the Cecropia obtusifolia / Azteca spp. association in Costa Rica. Tissue of ants, host plants and symbiotic pseudococcids were collected along three elevation transects on the Pacific slope of Costa Rica's Cordillera Ce...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-003-1406-1
更新日期:2004-01-01 00:00:00
abstract::Activity of soil decomposer microorganisms is generally limited by carbon availability, but factors controlling saprophagous soil animals remain largely unknown. In contrast to microorganisms, animals are unable to exploit mineral nutrient pools. Therefore, it has been suggested that soil animals, and earthworms in pa...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-003-1391-4
更新日期:2004-01-01 00:00:00
abstract::The decision how to allocate marginal resources to reproduction and growth can have important effects on associated life-history parameters as well as on population dynamics. In addition to showing variation among individuals in a population, such allocation rules may be either condition-dependent or fixed in differen...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-003-1390-5
更新日期:2003-12-01 00:00:00
abstract::The effect of the community composition of soil microbes on ecosystem processes has received relatively little attention. Here we examined the variation in soil microbial composition in a Yellowstone National Park grassland and the effect of that variation on the growth, in a greenhouse, of the dominant grass in the c...
journal_title:Oecologia
pub_type: 杂志文章
doi:10.1007/s00442-003-1385-2
更新日期:2003-12-01 00:00:00