Dynamic change characteristics of carbon exchange on sown grass and no-tillage peach orchard

Plant carbon sequestration is an effective way to abate the global warming. However, the field-scale carbon exchange on a peach orchard remains yet unclear. Here, using an eddy covariance technique, the carbon exchange and energy balance were analyzed on a coarse-sand-field, no-tillage, 12-year-old-peach orchard. The results showed that during full flowering, the ability to sequestrate carbon was remarkable, it reached on the peak of -0.33 mg (CO2)/(m2·s). During rapid growth, the Bowen ratio was under 0.3 and daily net carbon sequestration reached on the peak of -25.1 g (CO2)/(m2·d). During the leaf fall stage, there was a great deal of CO2 emissions, the peak value of carbon sequestration reached 0.60 mg (CO2)/(m2·s). During monitoring period, the daily average of net carbon sequestration and Bowen ratio was (1.22±1.56) and (-2.90±6.63)g(CO2)/(m2·d), respectively. The net carbon sequestration could reach-1052 g(CO2)/(m2·a) in a year. These results revealed that there were high carbon sequestration on a coarse-sand-field, no-tillage peach orchard. This research provides basic data for evaluating carbon sink function of orchard.