
TY  - JOUR
A1  - Araus, JL 
A1  - Buxo, R 
T1  - Changes in Carbon Isotope Discrimination in Grain Cereals From the North-Western Mediterranean Basin During the Past Seven Millenia
JF  - Functional Plant Biology
JO  - Functional Plant Biol.
Y1  - 1993
VL  - 20
IS  - 1
SP  - 117
EP  - 128
KW  - 
UR  - https://doi.org/10.1071/PP9930117 
N2  - Carbon isotope discrimination (&#916;) was determined for kernels of six-row barley and durum wheat cultivated in the north-western Mediterranean basin during the last seven millennia. Samples from the Neolithic, Bronze, Iron and Middle Ages came from different archaeological sites in Catalonia. Samples for the period 1910-20 and 1990 were also analysed. There was a slight decrease (P=0.10, carbonisation-corrected values) in &#916; from the Neolithic to the Iron Age period and a much steeper decrease from the Middle Ages to 1910-20 (P<0.01). Since water-use efficiency and isotope discrimination are negatively correlated, from the pattern of change in &#916; it is suggested that there has been a progressive increase in the water-use efficiency (WUE) of these cereals. Since the Middle Ages this has coincided with increases in atmospheric CO2 concentration. Thus, for a given relative humidity and air temperature, the estimated WUE (measured as the ratio of CO2 assimilation to transpiration) from the Neolithic to the Middle Ages samples ranged between 65-70% of present time WUE values, whereas WUE for 1910-20 was about 86% of present values. 
ER  -

