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    • Plusieurs versions

    Lianas reduce carbon accumulation and storage in tropical forests

    Van Der Heijden, Geertje M F, Powers, Jennifer S, Schnitzer, Stefan A
    Proceedings of the National Academy of Sciences of the United States of America, 27 October 2015, Vol.112(43), pp.13267-71 [Revue évaluée par les pairs]

    • Livre
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    Shareholders' liability : the comparative law yearbook of international business, special issue, 1993

    Campbell, Dennis, 1939-, Powers, Jennifer
    Center for International Legal Studies
    London ; Dordrecht [etc.] : Graham & Trotman : M. Nijhoff
    1994
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    Titre: Shareholders' liability : the comparative law yearbook of international business, special issue, 1993 / published under the auspices of the Center for International Legal Studies ; general ed. Dennis Campbell ; ed. Jennifer Powers
    Auteur: Campbell, Dennis, 1939-; Powers, Jennifer
    Contributeur: Center for International Legal Studies
    Editeur: London ; Dordrecht [etc.] : Graham & Trotman : M. Nijhoff
    Date: 1994
    Collation: XVIII, 505 p. ; 24 cm
    Collection: Comparative law yearbook of international business ; 1993, special issue
    Documents dans cette collection: Comparative law yearbook of international business
    Sujet RERO: Responsabilité (droit) - Droit comparé - Actionnaires
    Classification: dr-sys A 81 h
    dr-sys A 79.1 h
    Identifiant: 1859660487 (ISBN)
    No RERO: 1810070
    Permalien:
    http://data.rero.ch/01-1810070/html?view=FR_V1

    • Plusieurs versions

    Short and Long-Term Soil Moisture Effects of Liana Removal in a Seasonally Moist Tropical Forest

    Reid, Joseph Pignatello, Schnitzer, Stefan A, Powers, Jennifer S
    PLoS ONE, 2015, Vol.10(11) [Revue évaluée par les pairs]

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    Geographic bias of field observations of soil carbon stocks with tropical land-use changes precludes spatial extrapolation

    Powers , Jennifer S., Corre , Marife D., Twine , Tracy E., Veldkamp , Edzo
    Proceedings of the National Academy of Sciences of the United States of America, 2011, Vol.108(15), pp.6318-6322 [Revue évaluée par les pairs]
    AGRIS (Food and Agriculture Organization of the United Nations)
    Disponible
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    Titre: Geographic bias of field observations of soil carbon stocks with tropical land-use changes precludes spatial extrapolation
    Auteur: Powers , Jennifer S.; Corre , Marife D.; Twine , Tracy E.; Veldkamp , Edzo
    Editeur: National Academy of Sciences
    Date: 2011
    Sujet: Land Use Change ; Land Cover ; Emissions ; Economic Incentives ; Land Degradation ; Atmospheric Precipitation ; Mineralogy ; Field Experimentation ; Tropics ; Carbon Dioxide ; Meta-Analysis ; Carbon Sinks ; Carbon ; Clay Soils ; Issues And Policy ; Greenhouse Gases ; Landscapes ; Deforestation
    Description: Accurately quantifying changes in soil carbon (C) stocks with land-use change is important for estimating the anthropogenic fluxes of greenhouse gases to the atmosphere and for implementing policies such as REDD (Reducing Emissions from Deforestation and Degradation) that provide financial incentives to reduce carbon dioxide fluxes from deforestation and land degradation. Despite hundreds of field studies and at least a dozen literature reviews, there is still considerable disagreement on the direction and magnitude of changes in soil C stocks with land-use change. We conducted a meta-analysis of studies that quantified changes in soil C stocks with land use in the tropics. Conversion from one land use to another caused significant increases or decreases in soil C stocks for 8 of the 14 transitions examined. For the three land-use transitions with sufficient observations, both the direction and magnitude of the change in soil C pools depended strongly on biophysical factors of mean annual precipitation and dominant soil clay mineralogy. When we compared the distribution of biophysical conditions of the field observations to the area-weighted distribution of those factors in the tropics as a whole or the tropical lands that have undergone conversion, we found that field observations are highly unrepresentative of most tropical landscapes. Because of this geographic bias we strongly caution against extrapolating average values of land-cover change effects on soil C stocks, such as those generated through meta-analysis and literature reviews, to regions that differ in biophysical conditions. ; p. 6318-6322.
    Fait partie de: Proceedings of the National Academy of Sciences of the United States of America, 2011, Vol.108(15), pp.6318-6322
    Identifiant: 0027-8424 (ISSN)

    • Plusieurs versions

    Geographic bias of field observations of soil carbon stocks with tropical land-use changes precludes spatial extrapolation

    Powers, Jennifer S, Corre, Marife D, Twine, Tracy E, Veldkamp, Edzo
    Proceedings of the National Academy of Sciences of the United States of America, 12 April 2011, Vol.108(15), pp.6318-22 [Revue évaluée par les pairs]

    • Plusieurs versions

    Overlooking what is underground: Root:shoot ratios and coarse root allometric equations for tropical forests

    Waring, Bonnie G, Powers, Jennifer S
    Forest ecology and management, 01 February 2017, Vol.385, pp.10-15 [Revue évaluée par les pairs]

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    Do legumes and non-legumes tree species affect soil properties in unmanaged forests and plantations in Costa Rican dry forests?

    Gei , Maria G., Powers , Jennifer S.
    Soil biology & biochemistry, 2013, Vol.57, pp.264-272 [Revue évaluée par les pairs]
    AGRIS (Food and Agriculture Organization of the United Nations)
    Disponible
    Plus…
    Titre: Do legumes and non-legumes tree species affect soil properties in unmanaged forests and plantations in Costa Rican dry forests?
    Auteur: Gei , Maria G.; Powers , Jennifer S.
    Sujet: Soil Nutrient Dynamics ; Nutrient Availability ; Swietenia Macrophylla ; Habitats ; Secondary Forests ; Leptolobium Panamense ; Nitrates ; Nitrogen Fixation ; Dalbergia Retusa ; Dry Forests ; Nitrogen ; Soil Water ; Plantations ; Gliricidia Sepium ; Soil Properties ; Nodulation ; Acid Phosphatase ; Carbon ; Quercus Oleoides ; Enzyme Activity ; Trees ; Mineralization ; Legumes ; Species Diversity
    Description: Legume tree species, which are abundant in tropical dry forests, may be a critical regulator of soil nutrient dynamics because of their high foliar nitrogen (N) and potential for symbiotic N fixation. We investigated whether three legume tree species (Acosmium panamense, Dalbergia retusa, and Gliricidia sepium) have distinct soil chemistry under their crowns compared to nearby non-legume species (Rehdera trinervis, Swietenia macrophylla, and Quercus oleoides) when grown in two habitats: a diverse secondary forest or in 18-yr old monoculture plantations in northwestern Costa Rica. We quantified soil moisture, pH, labile carbon (C), inorganic N (NH₄ ⁺ and NO₃ ⁻), net N mineralization rates, total C and N, δ¹⁵N signature and enzyme activity. We predicted that legumes would have higher soil nutrient availability under their crowns, but that this effect would be more pronounced in plantations, where tree species diversity is low. In the forest, soils under Dalbergia had the highest values of total C and N, and extractable nitrate, whereas soils under Acosmium the highest N mineralization rates. The activity of acid phosphatase enzymes varied among the soils under different species in both habitats, with the highest activity in the soils under the legume Acosmium at the forest site. In the plantations, Acosmium had the highest values for total soil C and N, labile C, and potential N mineralization rates. We conclude that 1) the legume species did not have consistent effects as a functional group, possibly due to different amounts of nodulation in individuals within species, and 2) as hypothesized, the magnitude of the species effect was more pronounced in the plantations than in the diverse secondary forest. ; p. 264-272.
    Fait partie de: Soil biology & biochemistry, 2013, Vol.57, pp.264-272
    Identifiant: 0038-0717 (ISSN)

    • Plusieurs versions

    Do legumes and non-legumes tree species affect soil properties in unmanaged forests and plantations in Costa Rican dry forests?

    Gei, Maria G, Powers, Jennifer S
    Soil biology & biochemistry, February 2013, Vol.57, pp.264-272 [Revue évaluée par les pairs]

    • Plusieurs versions

    Macro- and micronutrient effects on decomposition of leaf litter from two tropical tree species: inferences from a short-term laboratory incubation

    Powers, Jennifer, Salute, Stefani
    Plant and Soil, 2011, Vol.346(1), pp.245-257 [Revue évaluée par les pairs]

    • Plusieurs versions

    The influence of seasonality and species effects on surface fine roots and nodulation in tropical legume tree plantations

    Gei, Maria, Powers, Jennifer
    Plant and Soil, 2015, Vol.388(1), pp.187-196 [Revue évaluée par les pairs]