Effects of clipping and soil compaction on growth, morphology and mycorrhizal colonization of Schizachyrium scoparium, a C4 bunchgrass.


:A factorial design of clipping and compaction was used to study the responses of Schizachyrium scoparium and its mycorrhizal symbionts to these stresses. All treatment combinations significantly reduced the growth and biomass of plants relative to controls. Compaction significantly reduced tillering and crown expansion while clipping increased tillering early in the growing season and reduced it later. Mycorrhizal colonization of roots was highest in the clipped plots and lowest in compacted plots. Spore number was highest in compacted plots and lowest in clipped plots. It appears that spore number may be negatively correlated with root growth since any treatment that reduced plant growth yielded higher spore numbers. The combination of clipping and compaction reduced plant growth the most, but had intermediate effects on mycorrhizal colonization and spore number.






Wallace LL




Has Abstract


1987-06-01 00:00:00














  • Foraging behavior of a freshwater copepod: Frequency changes in looping behavior at high and low prey densities.

    abstract::The foraging behavior of Mesocyclops edax in artificial patches of high and low prey density was examined. In low density patches Mesocyclops swam in an irregular curvilinear path with little or no looping behavior. In high density patches Mesocyclops exhibited extensive horizontal and vertical looping behavior. Horiz...


    pub_type: 杂志文章


    authors: Williamson CE

    更新日期:1981-09-01 00:00:00

  • Palearctic predator invades North American Great Lakes.

    abstract::Bythotrephes cederstroemii Schoedler, a predatory freshwater zooplankter (Crustacea: Cladocera), was first found in the Laurentian Great Lakes in December 1984. The first individuals were from Lake Huron, followed in 1985 with records from Lakes Erie and Ontario. By late August, 1986 the species had spread to southern...


    pub_type: 杂志文章


    authors: Lehman JT

    更新日期:1987-12-01 00:00:00

  • The spatial and temporal distribution pattern of the stoat (Mustela erminea L.).

    abstract::The distribution and movements of two stoat populations were studied by capture-recapture and tracking in the Swiss Jura Mountains. On the Brévine area in summer 1977 the population was at a high density phase and evenly distributed. A well established intrasexual territorial system was observed, with a high degree of...


    pub_type: 杂志文章


    authors: Debrot S,Mermod C

    更新日期:1983-08-01 00:00:00

  • Effects of carotenoid availability during laying on reproduction in the blue tit.

    abstract::Carotenoids are antioxidant pigments involved in several physiological processes and signalling in animals that cannot synthesise them and therefore must acquire them from food. We experimentally investigated the effects of carotenoid availability in the diet during egg laying on antioxidant deposition in egg yolk and...


    pub_type: 杂志文章


    authors: Biard C,Surai PF,Møller AP

    更新日期:2005-06-01 00:00:00

  • The economics of escape behaviour in the pea aphid, Acyrthosiphon pisum.

    abstract::Pea aphids have several alternative responses to the detection of alarm pheromone produced by conspecifics. One of these, dropping from the feeding site to the ground, is potentially costly owing to the risk of desiccation-induced mortality on the ground before another host plant can be reached. Both dropping and walk...


    pub_type: 杂志文章


    authors: Dill LM,Fraser AH,Roitberg BD

    更新日期:1990-07-01 00:00:00

  • Indirect effects of mutualism: ant-treehopper associations deter pollinators and reduce reproduction in a tropical shrub.

    abstract::Animal-pollinated plants can be susceptible to changes in pollinator availability. Honeydew-producing treehoppers frequently occur on inflorescences, potentially enhancing ant-mediated negative effects on pollination services. However, the effect of ant-attended, honeydew-producing insects on plant reproduction remain...


    pub_type: 杂志文章


    authors: Ibarra-Isassi J,Oliveira PS

    更新日期:2018-03-01 00:00:00

  • Trade-off between tolerance and resistance to infections: an experimental approach with malaria parasites in a passerine bird.

    abstract::Avian malaria parasites are known to have negative effects on their hosts, including consequences for reproductive success and survival. However, the outcome of disease may vary greatly among individuals, due to their particular genetic background, their past history of exposure to infections, or the way they respond ...


    pub_type: 杂志文章


    authors: Arriero E,Pérez-Tris J,Ramírez A,Remacha C

    更新日期:2018-12-01 00:00:00

  • Ectoparasitism as a possible cost of social life: a comparative analysis using Australian passerines (Passeriformes).

    abstract::The hypothesis that cooperative breeding entails a cost in terms of transmission of ectoparasites was tested by a comparative analysis among sympatric Australian passerines. The general trend found using the allometry method and outgroup analysis indicates that contagious ectoparasites are not more common on cooperati...


    pub_type: 杂志文章


    authors: Poiani A

    更新日期:1992-12-01 00:00:00

  • Long term effects of naturally elevated CO2 on mediterranean grassland and forest trees.

    abstract::We investigated the carbon supply status in species-rich mediterranean plant communities growing in a bowl-shaped 1-ha "CO2 spring" area near Sienna, Italy. A geothermic "lime-kiln" has provided these communities, for as long as historical records are available, with pure CO2 that mixes with ambient air at canopy leve...


    pub_type: 杂志文章


    authors: Körner C,Miglietta F

    更新日期:1994-09-01 00:00:00

  • Coevolution of pierid butterflies and their cruciferous foodplants : V. Habitat selection, community structure and speciation.

    abstract::Early models of hostplant exploitation by phytophagous insects suffer from unwarranted assumptions and may not be generally applicable. Wordmodels of the co-evolutionary approach may assume unwarranted evolutionary stability in 'strategic' explanations, whilst mathematical models derived from earlier optimal-diet stud...


    pub_type: 杂志文章


    authors: Courtney SP

    更新日期:1982-01-01 00:00:00

  • Short-term fluctuations in cellular immunity of tree swallows feeding nestlings.

    abstract::We examined cellular immunity of adult tree swallows feeding nestlings under variable weather conditions. Birds received an injection of phytohaemagglutinin (PHA), which causes a local swelling, reflecting the strength of T-cell-mediated immunocompetence. There was a negative relationship between the immune response a...


    pub_type: 杂志文章


    authors: Lifjeld JT,Dunn PO,Whittingham LA

    更新日期:2002-01-01 00:00:00

  • Effects of experimental food supplementation on movements of juvenile northern goshawks (Accipiter gentilis atricapillus).

    abstract::Food availability is thought to strongly influence the leaving phase of natal dispersal in animals with condition-dependent dispersal. We conducted a food supplementation experiment to determine the influence of extra food on the onset of dispersal and early dispersal movement patterns of 42 radio-tagged northern gosh...


    pub_type: 杂志文章


    authors: Kennedy PL,Ward JM

    更新日期:2003-01-01 00:00:00

  • Metapopulation dynamics over 25 years of a beetle, Osmoderma eremita, inhabiting hollow oaks.

    abstract::Osmoderma eremita is a species of beetle that inhabits hollows in ancient trees, which is a habitat that has decreased significantly during the last century. In southeastern Sweden, we studied the metapopulation dynamics of this beetle over a 25 year period, using capture-mark-recapture. The metapopulation size had be...


    pub_type: 杂志文章


    authors: Lindman L,Larsson MC,Mellbrand K,Svensson GP,Hedin J,Tranberg O,Ranius T

    更新日期:2020-12-01 00:00:00

  • Natural history collections and the future legacy of ecological research.

    abstract::Natural history collections are now being championed as key to broad ecological studies, especially those involving human impacts in the Anthropocene. However, collections are going through a crisis that threatens their present and future value, going beyond underfunding/understaffing to a more damaging practice: curr...


    pub_type: 杂志文章


    authors: Salvador RB,Cunha CM

    更新日期:2020-03-01 00:00:00

  • Assessment of anadromous salmon resources in the diet of the Alexander Archipelago wolf using stable isotope analysis.

    abstract::The Alexander Archipelago wolf (Canis lupus ligoni) is unique to southeast Alaska, occurring on islands south of Frederick Sound and along the mainland between Dixon Entrance and Yakutat Bay. Sitka black-tailed deer (Odocoileus hemionus sitkensis) are an important prey species for wolves across the southern part of th...


    pub_type: 杂志文章


    authors: Szepanski MM,Ben-David M,Van Ballenberghe V

    更新日期:1999-08-01 00:00:00

  • Diabetes and myocarditis in voles and lemmings at cyclic peak densities--induced by Ljungan virus?

    abstract::Although it is well-documented from theoretical studies that pathogens have the capacity to generate cycles, the occurrence and role of pathogens and disease have been poorly empirically studied in cyclic voles and lemmings. In screening for the occurrence of disease in cyclic vole and lemming populations, we found th...


    pub_type: 杂志文章


    authors: Niklasson B,Nyholm E,Feinstein RE,Samsioe A,Hörnfeldt B

    更新日期:2006-11-01 00:00:00

  • A model of competition.

    abstract::The paper considers a model of competition, based upon the Lotka-Volterra equations, which explicitly considers the effect of density independent mortality upon the outcome of competition. The model's possible application to wild Drosophila species in Europe are considered. ...


    pub_type: 杂志文章


    authors: Shorrocks B,Begon M

    更新日期:1975-12-01 00:00:00

  • Female blue tits with brighter yellow chests transfer more carotenoids to their eggs after an immune challenge.

    abstract::Female ornaments are present in many species, and it is more and more accepted that sexual or social selection may lead to their evolution. By contrast, the information conveyed by female ornaments is less well understood. Here, we investigated the links between female ornaments and maternal effects. In birds, an impo...


    pub_type: 杂志文章


    authors: Midamegbe A,Grégoire A,Staszewski V,Perret P,Lambrechts MM,Boulinier T,Doutrelant C

    更新日期:2013-10-01 00:00:00

  • The influence of vines on an oligohaline marsh community: results of a removal and fertilization study.

    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...


    pub_type: 杂志文章


    authors: Gough L,Grace JB

    更新日期:1997-10-01 00:00:00

  • Variability in grape phylloxera preference and performance on canyon grape (Vitis arizonica).

    abstract::We tested the deme-formation hypothesis experimentally with four populations of leaf-galling grape phylloxera, Daktulosphaira vitifoliae, and its host, canyon grape (Vitis arizonica). An experiment designed to examine preference and performance showed that phylloxera populations did not significantly prefer their orig...


    pub_type: 杂志文章


    authors: Kimberling DN,Price PW

    更新日期:1996-09-01 00:00:00

  • Carbon export is facilitated by sea urchins transforming kelp detritus.

    abstract::With the increasing imperative for societies to act to curb climate change by increasing carbon stores and sinks, it has become critical to understand how organic carbon is produced, released, transformed, transported, and sequestered within and across ecosystems. In freshwater and open-ocean systems, shredders play a...


    pub_type: 杂志文章


    authors: Filbee-Dexter K,Pedersen MF,Fredriksen S,Norderhaug KM,Rinde E,Kristiansen T,Albretsen J,Wernberg T

    更新日期:2020-01-01 00:00:00

  • [The influence of exogen and endogen factors on the moulting of Pygnogonum litorale (Ström)].

    abstract::Pycnogonum litorale has a terminal anecdysis. After attaining maturity it does not moult again. Maturity can be attained at different body size, the female usually being larger than the male.The pre-adult instar can also be entered at various body sizes. The duration of the pre-adult instar depends upon body size: At ...


    pub_type: 杂志文章


    authors: Schmidt HW

    更新日期:1971-09-01 00:00:00

  • Resource allocation of beech seedlings (Fagus sylvatica L.) -relationship to earthworm activity and soil conditions.

    abstract::The physiological activity and C and N allocation of beech seedlings planted in two different beech forest soils (acid brown earth, rendzina) were studied over 80 days. One adult earthworm Octolasion lacteum (Örley) was placed in half of the containers. Transpiration, CO2, assimilation, chlorophyll synthesis and N inc...


    pub_type: 杂志文章


    authors: Wolters V,Stickan W

    更新日期:1991-09-01 00:00:00

  • Patterns of plant species diversity during succession under different disturbance regimes.

    abstract::I suggest that between-community variations in diversity patterns during succession in plant communities are due to the effects of selection on life history strategies under different disturbance regimes. Natural disturbances to plant communities are simultaneously a source of mortality for some individuals and a sour...


    pub_type: 杂志文章


    authors: Denslow JS

    更新日期:1980-07-01 00:00:00

  • Interactions of species in an Anabaena flos-aquae association from the Plußsee (East-Holstein, Federal Republic of Germany).

    abstract::Fluorescent probes have been applied to study by epifluorescence microscopy interactions between species in an Anabaena flos-aquae association, derived from a freshwater community. Glycoconjugates (macromolecules containing carbohydrate residues) have been shown to play a vital role in recognition processes and in for...


    pub_type: 杂志文章


    authors: Müller U,Sengbusch PV

    更新日期:1983-05-01 00:00:00

  • Hierarchical habitat selection by barren-ground grizzly bears in the central Canadian Arctic.

    abstract::Using resource selection functions, we examined habitat selection patterns of barren-ground grizzly bears (Ursus arctos) in the central Canadian Arctic among and within home ranges. There was no difference between the sexes with regard to habitat selection patterns at the home range level (Wilks' λ, approx. F 11,11=1....


    pub_type: 杂志文章


    authors: McLoughlin PD,Case RL,Gau RJ,Cluff DH,Mulders R,Messier F

    更新日期:2002-06-01 00:00:00

  • Simulated drought regimes reveal community resilience and hydrological thresholds for altered decomposition.

    abstract::Future climate scenarios forecast a 10-50% decline in rainfall in Eastern Amazonia. Altered precipitation patterns may change important ecosystem functions like decomposition through either changes in physical and chemical processes or shifts in the activity and/or composition of species. We experimentally manipulated...


    pub_type: 杂志文章


    authors: Rodríguez Pérez H,Borrel G,Leroy C,Carrias JF,Corbara B,Srivastava DS,Céréghino R

    更新日期:2018-05-01 00:00:00

  • Reduced resistance to sediment-trapping turfs with decline of native kelp and establishment of an exotic kelp.

    abstract::Understanding the strength and type of interactions among species is vital to anticipate how ecosystems will respond to ongoing anthropogenic stressors. Here, we examine the ecological function of native (Ecklonia radiata) and invasive (Undaria pinnatifida) kelps in resisting shifts to sediment-trapping turf on reefs ...


    pub_type: 杂志文章


    authors: Reeves SE,Kriegisch N,Johnson CR,Ling SD

    更新日期:2018-12-01 00:00:00

  • Effects of habitat characteristics and interspecific interactions on co-occurrence patterns of saproxylic beetles breeding in tree boles after forest fire: null model analyses.

    abstract::It is often suggested that habitat attributes and interspecific interactions can cause non-random species co-occurrence patterns, but quantifying their contributions can be difficult. Null models that systematically exclude and include habitat effects can give information on the contribution of these factors to commun...


    pub_type: 杂志文章


    authors: Azeria ET,Ibarzabal J,Hébert C

    更新日期:2012-04-01 00:00:00

  • Host visitation sequence as a determinant of search persistence in fruit parasitic tephritid flies.

    abstract::We tested, through field experiments and simulation models, the hypothesis that fruit-searching tephritid fruit flies adjust their within-tree search persistence according to the sequence and timing of encounters with parasitized (i.e. egg-infested) and unparasitized Crataegus sp. host fruit. In the field, we presente...


    pub_type: 杂志文章


    authors: Roitberg BD,Prokopy RJ

    更新日期:1984-04-01 00:00:00