caa a22 4500 477111580 CHVBK 20180405111610.0 cr unu---uuuuu 170330e19960301xx s 000 0 eng 10.1007/BF00015416 doi (NATIONALLICENCE)springer-10.1007/BF00015416 Carbon fluxes in the rhizosphere of sweet chestnut seedlings ( Castanea sativa ) grown under two atmospheric CO2 concentrations: 14C partitioning after pulse labelling [Elektronische Daten] [Hervé Rouhier, Georges Billès, Laurent Billès, Pierre Bottner] Partitioning of 14C was assessed in sweet chestnut seedlings (Castanea sativa Mill.) grown in ambient and elevated atmospheric [CO2] environments during two vegetative cycles. The seedlings were exposed to 14CO2 atmosphere in both high and low [CO2] environments for a 6-day pulse period under controlled laboratory conditions. Six days after exposure to 14CO2, the plants were harvested, their dry mass and the radioactivity were evaluated. 14C concentration in plant tissues, root-soil system respiratory outputs and soil residues (rhizodeposition) were measured. Root production and rhizodeposition were increased in plants growing in elevated atmospheric [CO2]. When measuring total respiration, i.e. CO2 released from the root/soil system, it is difficult to separate CO2 originating from roots and that coming from the rhizospheric microflora. For this reason a model accounting for kinetics of exudate mineralization was used to estimate respiration of rhizospheric microflora and roots separately. Root activity (respiration and exudation) was increased at the higher atmospheric CO2 concentration. The proportion attributed to root respiration accounted for 70 to 90% of the total respiration. Microbial respiration was related to the amount of organic carbon available in the rhizosphere and showed a seasonal variation dependent upon the balance of root exudation and respiration. The increased carbon assimilated by plants grown under elevated atmospheric [CO2] stayed equally distributed between these increased root activities. ei]H Lambers Kluwer Academic Publishers, 1996 Castanea sativa nationallicence 14C-labelled nationallicence carbon allocation nationallicence [CO2] enrichment nationallicence exudation nationallicence respiration nationallicence rhizosphere nationallicence Rouhier Hervé C.E.F.E.-C.N.R.S., Route de mende, BP 5051, F-34033, Montpellier Cedex, France aut Billès Georges C.E.F.E.-C.N.R.S., Route de mende, BP 5051, F-34033, Montpellier Cedex, France aut Billès Laurent C.E.F.E.-C.N.R.S., Route de mende, BP 5051, F-34033, Montpellier Cedex, France aut Bottner Pierre C.E.F.E.-C.N.R.S., Route de mende, BP 5051, F-34033, Montpellier Cedex, France aut Plant and Soil Kluwer Academic Publishers; gopher://gopher.wkap.nl 180/1(1996-03-01), 101-111 0032-079X 180:1<101 1996 180 11104 https://doi.org/10.1007/BF00015416 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00015416 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Rouhier Hervé C.E.F.E.-C.N.R.S., Route de mende, BP 5051, F-34033, Montpellier Cedex, France aut NATIONALLICENCE 700 1- Billès Georges C.E.F.E.-C.N.R.S., Route de mende, BP 5051, F-34033, Montpellier Cedex, France aut NATIONALLICENCE 700 1- Billès Laurent C.E.F.E.-C.N.R.S., Route de mende, BP 5051, F-34033, Montpellier Cedex, France aut NATIONALLICENCE 700 1- Bottner Pierre C.E.F.E.-C.N.R.S., Route de mende, BP 5051, F-34033, Montpellier Cedex, France aut NATIONALLICENCE 773 0- Plant and Soil Kluwer Academic Publishers; gopher://gopher.wkap.nl/ 180/1(1996-03-01), 101-111 0032-079X 180:1<101 1996 180 11104 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer