Xylem and soil CO2 fluxes in a Quercus pyrenaica Willd. coppice: root respiration increases with clonal size

Table 5 Fluxes of root-respired CO₂ through xylem (F _T, mmol CO₂ stem⁻¹ day⁻¹) and root-respired CO₂ diffused through soil to the atmosphere (F _S16-root, mmol CO₂ stem⁻¹ day⁻¹). To compare magnitudes between fluxes, the ratio F _T/F _S16-root is shown on a percentage basis. F_S16-root was estimated at 16 °C for comparison

	F _T	F _S16-root	F _T/F _S16-root (%)
Average fluxes among clones^a	8.21 (2.89)	333.47 (53.69)	2.46
Average fluxes within clone LARGE1^a	15.63 (10.45)	881.85 (231.99)	1.77
Average fluxes within clone LARGE2^a	9.35 (1.31)	511.92 (192.42)	1.83
Average fluxes over the sampled range of clonal extension^b	7.08 (0.90)	399.53 (53.96)	1.77

^aMeasured values (F _S16-root was not measured in clones SMALL1 and SMALL2)
^bFluxes predicted from F _T and F _S16-root relationships with clonal extension (Fig. 4 (c, e))

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