Are rivers just big streams? A pulse method to quantify nitrogen demand in a large river.


:Given recent focus on large rivers as conduits for excess nutrients to coastal zones, their role in processing and retaining nutrients has been overlooked and understudied. Empirical measurements of nutrient uptake in large rivers are lacking, despite a substantial body of knowledge on nutrient transport and removal in smaller streams. Researchers interested in nutrient transport by rivers (discharge >10000 L/s) are left to extrapolate riverine nutrient demand using a modeling framework or a mass balance approach. To begin to fill this knowledge gap, we present data using a pulse method to measure inorganic nitrogen. (N) transport and removal in the Upper Snake River, Wyoming, USA (seventh order, discharge 12000 L/s). We found that the Upper Snake had surprisingly high biotic demand relative to smaller streams in the same river network for both ammonium (NH4+) and nitrate (NO3-). Placed in the context of a meta-analysis of previously published nutrient uptake studies, these data suggest that large rivers may have similar biotic demand for N as smaller tributaries. We also found that demand for different forms of inorganic N (NH4+ vs. NO3-) scaled differently with stream size. Data from rivers like the Upper Snake and larger are essential for effective water quality management at the scale of river networks. Empirical measurements of solute dynamics in large rivers are needed to understand the role of whole river networks (as opposed to stream reaches) in patterns of nutrient export at regional and continental scales.






Tank JL,Rosi-Marshall EJ,Baker MA,Hall RO Jr




Has Abstract


2008-10-01 00:00:00














  • Testing the evolution of increased competitive ability (EICA) hypothesis in a novel framework.

    abstract::The "evolution of increased competitive ability" (EICA) hypothesis proposes that escape from natural enemies, e.g., after transcontinental introductions, alters the selection regime because costly defenses no longer enhance fitness. Such an evolutionary loss of defenses enables resources to be directed toward growth o...


    pub_type: 杂志文章


    authors: Handley RJ,Steinger T,Treier UA,Müller-Schärer H

    更新日期:2008-02-01 00:00:00

  • Diffusion about the mean drift location in a biased random walk.

    abstract::Random walks are used to model movement in a wide variety of contexts: from the movement of cells undergoing chemotaxis to the migration of animals. In a two-dimensional biased random walk, the diffusion about the mean drift position is entirely dependent on the moments of the angular distribution used to determine th...


    pub_type: 杂志文章


    authors: Codling EA,Bearon RN,Thorn GJ

    更新日期:2010-10-01 00:00:00

  • Fish introductions and light modulate food web fluxes in tropical streams: a whole-ecosystem experimental approach.

    abstract::Decades of ecological study have demonstrated the importance of top-down and bottom-up controls on food webs, yet few studies within this context have quantified the magnitude of energy and material fluxes at the whole-ecosystem scale. We examined top-down and bottom-up effects on food web fluxes using a field experim...


    pub_type: 杂志文章


    authors: Collins SM,Thomas SA,Heatherly T 2nd,MacNeill KL,Leduc AO,López-Sepulcre A,Lamphere BA,El-Sabaawi RW,Reznick DN,Pringle CM,Flecker AS

    更新日期:2016-11-01 00:00:00

  • Responses of a bacterial pathogen to phosphorus limitation of its aquatic invertebrate host.

    abstract::Host nutrition is thought to affect the establishment, persistence, and severity of pathogenic infections. Nutrient-deficient foods possibly benefit pathogens by constraining host immune function or benefit hosts by limiting parasite growth and reproduction. However, the effects of poor elemental food quality on a hos...


    pub_type: 杂志文章


    authors: Frost PC,Ebert D,Smith VH

    更新日期:2008-02-01 00:00:00

  • Everybody loses: intraspecific competition induces tragedy of the commons in Allenby's gerbils.

    abstract::Interference competition may lead to a tragedy of the commons in which individuals driven by self-interest reduce the fitness of the entire group. We investigated this hypothesis in Allenby's gerbils, Gerbillus andersoni allenbyi, by comparing foraging behaviors of single vs. pairs of gerbils. We recorded strong inter...


    pub_type: 杂志文章


    authors: Berger-Tal O,Embar K,Kotler BP,Saltz D

    更新日期:2015-01-01 00:00:00

  • Ocean warming increases threat of invasive species in a marine fouling community.

    abstract::We addressed the potential for climate change to facilitate invasions and precipitate shifts in community composition by testing effects of ocean warming on species in a marine fouling community in Bodega Harbor, Bodega Bay, California, USA. First, we determined that introduced species tolerated significantly higher t...


    pub_type: 杂志文章


    authors: Sorte CJ,Williams SL,Zerebecki RA

    更新日期:2010-08-01 00:00:00

  • A distributed experiment demonstrates widespread sodium limitation in grassland food webs.

    abstract::Sodium (Na) has a unique role in food webs as a nutrient primarily limiting for plant consumers, but not other trophic levels. Environmental Na levels vary with proximity to coasts, local geomorphology, climate, and with anthropogenic inputs (e.g., road salt). We tested two key predictions across 54 grasslands in Nort...


    pub_type: 杂志文章


    authors: Welti EAR,Sanders NJ,de Beurs KM,Kaspari M

    更新日期:2019-03-01 00:00:00

  • Soil drivers of local-scale tree growth in a lowland tropical forest.

    abstract::Soil nutrients influence the distribution of tree species in lowland tropical forests, but their effect on productivity, especially at local scales, remains unclear. We used tree census, canopy occupancy, and soil data from the Barro Colorado Island (BCI; Panama) 50-ha forest dynamics plot to investigate the influence...


    pub_type: 杂志文章


    authors: Zemunik G,Davies SJ,Turner BL

    更新日期:2018-12-01 00:00:00

  • Allometric scaling predicts preferences for burned patches in a guild of East African grazers.

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    pub_type: 杂志文章


    authors: Sensenig RL,Demment MW,Laca EA

    更新日期:2010-10-01 00:00:00

  • Reduced pollinator service and elevated pollen limitation at the geographic range limit of an annual plant.

    abstract::Mutualisms are well known to influence individual fitness and the population dynamics of partner species, but little is known about whether they influence species distributions and the location of geographic range limits. Here, we examine the contribution of plant-pollinator interactions to the geographic range limit ...


    pub_type: 杂志文章


    authors: Moeller DA,Geber MA,Eckhart VM,Tiffin P

    更新日期:2012-05-01 00:00:00

  • Allochthonous aquatic subsidies alleviate predation pressure in terrestrial ecosystems.

    abstract::The input of external energy and matter in recipient ecosystems can act as a bottom-up force that subsidizes consumers, with subsequent cascading effects throughout the food web. Depending on the amount of input, dietary preference, and the strength of trophic links, allochthonous resources generally play a stabilizin...


    pub_type: 杂志文章


    authors: Recalde FC,Breviglieri CPB,Romero GQ

    更新日期:2020-08-01 00:00:00

  • Ecological impacts of genotypic diversity in the clonal seagrass Zostera marina.

    abstract::Genetic diversity, like species diversity, can have important consequences for communities and ecosystems. However, little is known about whether the effects of genetic diversity demonstrated in experimental assemblages are of sufficient strength to generate patterns in natural systems. We conducted a survey of eelgra...


    pub_type: 杂志文章


    authors: Hughes AR,Stachowicz JJ

    更新日期:2009-05-01 00:00:00

  • Variable intertidal temperature explains why disease endangers black abalone.

    abstract::Epidemiological theory suggests that pathogens will not cause host extinctions because agents of disease should fade out when the host population is driven below a threshold density. Nevertheless, infectious diseases have threatened species with extinction on local scales by maintaining high incidence and the ability ...


    pub_type: 杂志文章


    authors: Ben-Horin T,Lenihan HS,Lafferty KD

    更新日期:2013-01-01 00:00:00

  • Efficiency of crustacean zooplankton in transferring allochthonous carbon in a boreal lake.

    abstract::Increased incorporation of terrestrial organic matter (t-OM) into consumer biomass (allochthony) is believed to reduce growth capacity. In this study, we examined the relationship between crustacean zooplankton allochthony and production in a boreal lake that displays strong seasonal variability in t-OM inputs. Contra...


    pub_type: 杂志文章


    authors: Grosbois G,Vachon D,Del Giorgio PA,Rautio M

    更新日期:2020-06-01 00:00:00

  • Nikolaeva et al.'s reference book on seed dormancy and germination.

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    pub_type: 杂志文章


    authors: Rosbakh S,Baskin CC,Baskin JM

    更新日期:2020-07-01 00:00:00

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    pub_type: 杂志文章


    authors: Kasumovic MM,Bruce MJ,Herberstein ME,Andrade MC

    更新日期:2009-08-01 00:00:00

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    pub_type: 杂志文章


    authors: Petermann JS,Fergus AJ,Turnbull LA,Schmid B

    更新日期:2008-09-01 00:00:00

  • An incidence-based richness estimator for quadrats sampled without replacement.

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    pub_type: 杂志文章


    authors: Shen TJ,He F

    更新日期:2008-07-01 00:00:00

  • The stability of African savannas: insights from the indirect estimation of the parameters of a dynamic model.

    abstract::Savannas are characterized by a competitive tension between grasses and trees, and theoretical models illustrate how this competitive tension is influenced by resource availability, competition for these resources, and disturbances. How this universe of theoretical possibilities translates into the real world is, howe...


    pub_type: 杂志文章


    authors: Higgins SI,Scheiter S,Sankaran M

    更新日期:2010-06-01 00:00:00

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    pub_type: 杂志文章


    authors: LaRue EA,Holland JD,Emery NC

    更新日期:2018-08-01 00:00:00

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    pub_type: 杂志文章


    authors: Frick WF,Cheng TL,Langwig KE,Hoyt JR,Janicki AF,Parise KL,Foster JT,Kilpatrick AM

    更新日期:2017-03-01 00:00:00

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    pub_type: 杂志文章


    authors: HilleRisLambers J,Harpole WS,Schnitzer S,Tilman D,Reich PB

    更新日期:2009-07-01 00:00:00

  • When is a type III functional response stabilizing? Theory and practice of predicting plankton dynamics under enrichment.

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    pub_type: 杂志文章


    authors: Uszko W,Diehl S,Pitsch N,Lengfellner K,Müller T

    更新日期:2015-12-01 00:00:00

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    pub_type: 杂志文章


    authors: Thibaut LM,Connolly SR

    更新日期:2020-01-01 00:00:00

  • Chihuahuan Desert kangaroo rats: nonlinear effects of population dynamics, competition, and rainfall.

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    pub_type: 杂志文章


    authors: Lima M,Ernest SK,Brown JH,Belgrano A,Stenseth NC

    更新日期:2008-09-01 00:00:00

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    pub_type: 杂志文章


    authors: Brooks CP

    更新日期:2006-04-01 00:00:00

  • A depth refugium from catastrophic coral bleaching prevents regional extinction.

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    pub_type: 杂志文章


    authors: Smith TB,Glynn PW,Maté JL,Toth LT,Gyory J

    更新日期:2014-06-01 00:00:00

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    pub_type: 杂志文章


    authors: Lattuada M,Wilke T,Raes N

    更新日期:2020-09-01 00:00:00

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    pub_type: 杂志文章


    authors: Schmitt RJ,Holbrook SJ

    更新日期:2007-05-01 00:00:00

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    pub_type: 杂志文章


    authors: De Roos AM,Galic N,Heesterbeek H

    更新日期:2009-04-01 00:00:00