Foraging and leaf-cutting of the desert gardening ant Acromyrmex versicolor versicolor (Pergande) (Hymenoptera: Formicidae).

abstract：:Disturbance may play an important role in generating patterns of abundance and distribution of biotic assemblages, particularly if its impact differs among habitat patches. Despite much speculation concerning the probable importance of spatial variation in the response of stream fauna to flooding, empirical work on pa...

journal_title：Oecologia

authors： Palmer MA,Arensburger P,Martin AP,Denman DW

更新日期：1996-01-01 00:00:00

abstract：:Host plant use and availability were determined in early nymphal and adult-stage Schistocerca emarginata (=lineata) (Orthoptera: Acrididae) populations at six localities in Texas, USA. Early instar nymphal populations were feeding almost exclusively on either Ptelea trifoliata (Rutaceae) or Rubus trivialis (Rosaceae)....

journal_title：Oecologia

authors： Sword GA,Dopman EB

更新日期：1999-08-01 00:00:00

abstract：:Long-termed fumigation of pea seedlings with SO2 caused typical alterations of the concentration of free glutamate and glutamine as well as fluctuations of the activity of glutamate dehydrogenase and glutamine synthetase. Shortly after the beginning of the fumigation with low concentrations of SO2 (up to 0,3 ppm) the ...

journal_title：Oecologia

authors： Jäger HJ,Pahlich E

更新日期：1972-06-01 00:00:00

abstract：:A reanalysis of data presented by Henneman (1983) to examine the relationship between intrinsic rate of increase and basal metabolism suggests there is no statistically significant correlation between the two variables when both are treated with comparable statistical techniques. In addition, I suggest there is no the...

journal_title：Oecologia

authors： Hayssen V

更新日期：1984-11-01 00:00:00

abstract：:Severe droughts may alter the reproductive phenology of tropical tree species, but our understanding of these effects has been hampered by confounded variation in drought, light and other factors during natural drought events. We used a large-scale experimental reduction of throughfall in an eastern-central Amazon for...

journal_title：Oecologia

authors： Brando P,Ray D,Nepstad D,Cardinot G,Curran LM,Oliveira R

更新日期：2006-11-01 00:00:00

abstract：:The effects of competitive suppression by vines on the non-vine plant community have received little attention in temperate habitats. This study investigated the impact vines have on their herbaceous hosts in a wetland community at two soil fertility levels. Plots in an oligohaline marsh were treated in a 2 × 2 factor...

journal_title：Oecologia

authors： Gough L,Grace JB

更新日期：1997-10-01 00:00:00

abstract：:We performed a factorial combination of seed additions, surface soil disturbance, and protection from potential seed predation in experimental plots to elucidate the relative importance of each factor in the recruitment of scarlet gilia seedlings. We detected a significant interaction between seed addition and surface...

journal_title：Oecologia

authors： Juenger T,Bergelson J

更新日期：2000-05-01 00:00:00

abstract：:External hyphae of vesicular-arbuscular mycorrhizal (VAM) fungi were quantified over a growing season in a reconstructed tallgrass prairie and an ungrazed cool-season pasture. In both sites, hyphal lengths increased throughout the growing season. Peak external hyphal lengths were 111 m cm-3 of soil in the prairie and ...

journal_title：Oecologia

authors： Miller RM,Jastrow JD,Reinhardt DR

更新日期：1995-07-01 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

authors： Lange OL,Geiger IL,Schulze E-

更新日期：1977-09-01 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

authors： Lechowicz MJ

更新日期：1978-01-01 00:00:00

abstract：:From 1977 through 1983 we conducted experiments on a desert rodent community where supplemental seeds were added or certain rodent species and ants were removed from 0.25-ha fenced plots in a Chihuahuan Desert site in southeastern Arizona, USA. In this paper we examine the patterns of microhabitat use relative to vege...

journal_title：Oecologia

authors： Bowers MA,Thompson DB,Brown JH

更新日期：1987-04-01 00:00:00

abstract：:Holling's (1992) proposition that discontinuities in biotic and abiotic processes generate structure in ecological systems is examined experimentally by imposing size-specific perturbations on marine sediment assemblages. Two kinds of perturbations were applied: organic enrichment and predation, each at two levels. Pe...

journal_title：Oecologia

authors： Raffaelli D,Hall S,Emes C,Manly B

更新日期：2000-02-01 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

authors： Krist M,Remes V,Uvírová L,Nádvorník P,Bures S

更新日期：2004-06-01 00:00:00

abstract：:Although host preferences in phytophagous insects may be generated by several factors, few studies have simultaneously examined several potential host choice determinants. In this study we tested the impact of the following potential host choice determinants on host preference of the semi-aquatic lepidopteran Munroess...

journal_title：Oecologia

authors： Dorn NJ,Cronin G,Lodge DM

更新日期：2001-08-01 00:00:00

abstract：:Ecological stoichiometry has advanced food web ecology by emphasising the importance of food quality over food quantity for herbivores. Here, we focus on the effects of abiotic factors such as nutrients and light (known to influence food quality) on grazer growth rates. As model organism we used the mudsnail Potamopyr...

journal_title：Oecologia

authors： Liess A,Lange K

更新日期：2011-09-01 00:00:00

abstract：:Density-dependent mortality may regulate many populations, but due to an offshore larval phase in benthic marine organisms, it is often difficult to quantify the effects of mortality of arriving individuals. We added approximately 600 recruit-sized individuals onto coral reef that parallels patterns in naturally settl...

journal_title：Oecologia

authors： Brunton BJ,Booth DJ

更新日期：2003-11-01 00:00:00

abstract：:Predation pressure and resource availability often interact in structuring herbivore communities, with their relative influence varying in space and time. The operation of multiple ecological pressures and guild-specific herbivore responses may combine to override simple predictions of how the roles of plant quality a...

journal_title：Oecologia

authors： Zehnder CB,Stodola KW,Cooper RJ,Hunter MD

更新日期：2010-12-01 00:00:00

abstract：:Abiotic drivers of environmental stress have been found to induce CAM expression (nocturnal carboxylation) in facultative CAM species such as Mesembryanthemum crystallinum. The role played by biotic factors such as competition with non-CAM species in affecting CAM expression, however, remains largely understudied. Thi...

journal_title：Oecologia

authors： Yu K,D'Odorico P,Li W,He Y

更新日期：2017-06-01 00:00:00

abstract：:Spontaneous bleeding of sugar-rich sap from cambial-deep incisions in the bark of trunks was demonstrated for Eucalyptus globulus and other eucalypts across a range of localities and seasonal conditions in south-west Australia. High levels of sucrose and raffinose (up to 31% w/v total sugars) were present in the exuda...

journal_title：Oecologia

authors： Pate J,Shedley E,Arthur D,Adams M

更新日期：1998-12-01 00:00:00

abstract：:Data on soil nutrient availability for humid tropical forests are often reported, but are rarely integrated in an ecologically meaningful way with other measures of nutrient cycling. In this paper, estimates of soil nutrient availability and the inverse of litterfall nutrient concentrations (as an index of plant nutri...

journal_title：Oecologia

authors： Silver WL

更新日期：1994-08-01 00:00:00

abstract：:The model of Meats (1974a) is tested against Laughlin's (1967a) data on growth in the field. A good measure of agreement is found. The model is then used to investigate the consequences of the univoltine T. paludosa starting its life cycle (flight season) at various dates in the range quoted by Coulson (1962)-i.e. fro...

journal_title：Oecologia

authors： Meats A

更新日期：1975-06-01 00:00:00

abstract：:Myrmecophytic symbioses are widespread in tropical ecosystems and their diversity makes them useful tools for understanding the origin and evolution of mutualisms. Obligate ant-plants, or myrmecophytes, provide a nesting place, and, often, food to a limited number of plant-ant species. In exchange, plant-ants protect ...

journal_title：Oecologia

authors： Orivel J,Lambs L,Malé PJ,Leroy C,Grangier J,Otto T,Quilichini A,Dejean A

更新日期：2011-02-01 00:00:00

abstract：:Recent research has shown that many mutualistic communities display non-random structures. While our understanding of the structural properties of mutualistic communities continues to improve, we know little of the biological variables resulting in them. Mutualistic communities include those formed between ants and ex...

journal_title：Oecologia

authors： Chamberlain SA,Kilpatrick JR,Holland JN

更新日期：2010-11-01 00:00:00

abstract：:Ant metapleural glands secrete surface antibiotics that affect pollen as well as bacteria and fungi. This may be one reason why ant pollination is rare. It is predicted that pollination by ants is possible only in the presence of certain ant and/or plant traits. Two traits are investigated; first, absence of the metap...

journal_title：Oecologia

authors： Peakall R,Angus CJ,Beattie AJ

更新日期：1990-10-01 00:00:00

abstract：:Herbivores can have strong deleterious effects on plant growth, reproduction, and even survival. Because these effects might be strongly interrelated, the direct consumptive effects of herbivores and a variety of indirect effects are difficult to untangle. Reductions in growth, for example, may strongly impact the flo...

journal_title：Oecologia

authors： Brys R,Shefferson RP,Jacquemyn H

更新日期：2011-06-01 00:00:00

abstract：:Predation by Saduria entomon on the depositfeeding amphipods Monoporeia (=Pontoporeia) affinis and Pontoporeia femorata was studied in laboratory experiments. Prey vulnerabilities were compared in singleprey treatments and in mixed-prey treatments, where the proportions of the two species were varied at one total dens...

journal_title：Oecologia

authors： Hill C,Elmgren R

更新日期：1992-08-01 00:00:00

abstract：:The ribulose-1,5-bis-phosphate (RBPC) 14CO2 fixation rate was measured at four different temperatures, 5°, 15°, 25° and 35° C, in three populations of Espeletia schultzii at different altitudes, 3100, 3550 and 4200 ma.s.l. The fixation rate increased with temperature increase in the populations studied. The population...

journal_title：Oecologia

authors： Castrillo M

更新日期：1995-02-01 00:00:00

abstract：:The influence of irrigation and nitrogen fertilization in early summer on root and shoot growth of Atriplex confertifolia, a C4 shrub species, was examined in a cold-winter desert community in northern Utah. Soil water and xylem pressure potentials were monitored during the summer period.At the time of watering the su...

journal_title：Oecologia

authors： Hodgkinson KC,Johnson PS,Norton BE

更新日期：1978-01-01 00:00:00

abstract：:Plants of white clover Trifolium repens were grown under the canopies of three grass species, Lolium perenne, Agrostis tenuis and Holcus lanatus, and under simulated canopies of black polythene and controls were exposed to unfiltered natural radiation. The canopies were adjusted so that they transmitted equal intensit...

journal_title：Oecologia

authors： Thompson L,Harper JL

更新日期：1988-04-01 00:00:00

abstract：:Experiments are described which demonstrate that the seeds of the desert species Blepharis persica are capable of germinating within 50 min of being exposed to moisture. Their radicles reach a length of about 49 mm within the first 24 h from wetting. The seeds can germinate in light and dark at temperatures ranging fr...

journal_title：Oecologia

authors： Gutterman Y

更新日期：1972-06-01 00:00:00