TY - JOUR

T1 - Carbon turnover in a crop rotation under free air CO 2 enrichment (FACE)

AU - Weigel, Hans-Joachim

AU - Pacholski, A.

AU - Burkart, S.

AU - Helal, M.

AU - Heinemeyer, Otto

AU - Kleikamp, B.

AU - Manderscheid, Remigius

AU - Frühauf, Cathleen

AU - Hendrey, G.F.

AU - Lewin, K.

AU - Nagy, J.

PY - 2005/12/1

Y1 - 2005/12/1

N2 - Mostly based on assumptions derived from controlled-environment studies, predicted future atmospheric CO 2 concentrations [CO 2] are expected to have considerable impacts on carbon (C) turnover in agro-ecosystems. In order to allow the in situ examination of C-transformations in the plant-soil system of arable crop rotations under future [CO 2], a free air carbon dioxide enrichment (FACE) experiment (550 μmol mol -1 CO 2) was started at Braunschweig, Germany in 1999. The crop rotation under investigation comprised winter barley, a cover crop (ryegrass), sugar beets and winter wheat. Assessments of CO 2 effects included the determination of above- and belowground biomass production, measurements of canopy CO 2- and H 2O- fluxes, soil microbial biomass and in situ soil respiration. The results obtained during the 1st crop rotation cycle (3 years) showed that for the selected crops elevated [CO 2] entailed significant positive effects (P < 0.05) on aboveground (6%-14% stimulation) and belowground biomass production (up to 90% stimulation), while canopy evapotranspiration was reduced. This resulted in increased soil water content. Also, depending on crop type and season, high CO 2 stimulated in situ soil respiration (up to 30%), while soil microbial biomass did not show significant responses to elevated [CO 2] during the first rotation cycle.

AB - Mostly based on assumptions derived from controlled-environment studies, predicted future atmospheric CO 2 concentrations [CO 2] are expected to have considerable impacts on carbon (C) turnover in agro-ecosystems. In order to allow the in situ examination of C-transformations in the plant-soil system of arable crop rotations under future [CO 2], a free air carbon dioxide enrichment (FACE) experiment (550 μmol mol -1 CO 2) was started at Braunschweig, Germany in 1999. The crop rotation under investigation comprised winter barley, a cover crop (ryegrass), sugar beets and winter wheat. Assessments of CO 2 effects included the determination of above- and belowground biomass production, measurements of canopy CO 2- and H 2O- fluxes, soil microbial biomass and in situ soil respiration. The results obtained during the 1st crop rotation cycle (3 years) showed that for the selected crops elevated [CO 2] entailed significant positive effects (P < 0.05) on aboveground (6%-14% stimulation) and belowground biomass production (up to 90% stimulation), while canopy evapotranspiration was reduced. This resulted in increased soil water content. Also, depending on crop type and season, high CO 2 stimulated in situ soil respiration (up to 30%), while soil microbial biomass did not show significant responses to elevated [CO 2] during the first rotation cycle.

KW - Ecosystems Research

KW - Agroecosystems

KW - Carbon

KW - Elevated CO

KW - FACE

KW - Soil

UR - http://www.scopus.com/inward/record.url?scp=28844455007&partnerID=8YFLogxK

M3 - Journal articles

AN - SCOPUS:28844455007

VL - 15

SP - 728

EP - 738

JO - Pedosphere

JF - Pedosphere

SN - 1002-0160

IS - 6

ER -