Increases in the flux of carbon belowground stimulate nitrogen uptake and sustain the long-term enhancement of forest productivity under elevated CO2

TY - JOUR

T1 - Increases in the flux of carbon belowground stimulate nitrogen uptake and sustain the long-term enhancement of forest productivity under elevated CO2

AU - Drake, John E.

AU - Gallet-Budynek, Anne

AU - Hofmockel, Kirsten S.

AU - Bernhardt, Emily S.

AU - Billings, Sharon A.

AU - Jackson, Robert B.

AU - Johnsen, Kurt S.

AU - Lichter, John

AU - McCarthy, Heather R.

AU - McCormack, M. Luke

AU - Moore, David J. P.

AU - Oren, Ram

AU - Palmroth, Sari

AU - Phillips, Richard P.

AU - Pippen, Jeffrey S.

AU - Pritchard, Seth G.

AU - Treseder, Kathleen K.

AU - Schlesinger, William H.

AU - DeLucia, Evan H.

AU - Finzi, Adrien C.

PY - 2011/4

Y1 - 2011/4

N2 - P>The earth's future climate state is highly dependent upon changes in terrestrial C storage in response to rising concentrations of atmospheric CO2. Here we show that consistently enhanced rates of net primary production (NPP) are sustained by a C-cascade through the root-microbe-soil system; increases in the flux of C belowground under elevated CO2 stimulated microbial activity, accelerated the rate of soil organic matter decomposition and stimulated tree uptake of N bound to this SOM. This process set into motion a positive feedback maintaining greater C gain under elevated CO2 as a result of increases in canopy N content and higher photosynthetic N-use efficiency. The ecosystem-level consequence of the enhanced requirement for N and the exchange of plant C for N belowground is the dominance of C storage in tree biomass but the preclusion of a large C sink in the soil.

AB - P>The earth's future climate state is highly dependent upon changes in terrestrial C storage in response to rising concentrations of atmospheric CO2. Here we show that consistently enhanced rates of net primary production (NPP) are sustained by a C-cascade through the root-microbe-soil system; increases in the flux of C belowground under elevated CO2 stimulated microbial activity, accelerated the rate of soil organic matter decomposition and stimulated tree uptake of N bound to this SOM. This process set into motion a positive feedback maintaining greater C gain under elevated CO2 as a result of increases in canopy N content and higher photosynthetic N-use efficiency. The ecosystem-level consequence of the enhanced requirement for N and the exchange of plant C for N belowground is the dominance of C storage in tree biomass but the preclusion of a large C sink in the soil.

U2 - 10.1111/j.1461-0248.2011.01593.x

DO - 10.1111/j.1461-0248.2011.01593.x

M3 - Letter

VL - 14

SP - 349

EP - 357

JO - ECOLOGY LETTERS

JF - ECOLOGY LETTERS

IS - 4

ER -