Effects of human-caused disturbance on nitrous oxide flux from Cyperus malaccensis marsh in the Minjiang River estuary
N2O fluxes from the Cyperus malaccensis var. brevifolius marsh were measured using enclosed dark static chamber and float chamber technique during three periods (before flood, in course of flooding and ebbing, and after ebb), and N2O fluxes from the invasive Spartina alterniflora Loisel marsh, C. malaccensis marsh added nutrient and bare marsh treaded by peoples were also determined before flood and after ebb in the intertidal zones Minjiang River estuary. The results showed that N2O fluxes from invasive S. alterniflora marsh and C. malaccensis marsh were 15.37μg/(m2·h) and 18.77μg/(m2·h), respectively, S. alterniflora invasion decreased N2O fluxes from C. malaccensis marsh, and the reduction effect on N2O fluxes from C. malaccensis marsh related closely to tide, and not to seasonal variation. N2O fluxes from C. malaccensis marsh increased after adding nutrient. The average N2O flux was 163.72μg/(m2·h) after adding the nutrient in autumn, and were 227.62μg/(m2·h) and 1178.64μg/(m2·h) in submerged and exposed periods in C. malaccensis marsh at high tide dates in spring, respectively. The peak of N2O emission occurred earlier during tidal inundation period. Average N2O flux was -0.76μg/(m2·h) from bare marsh, which suggested that N2O fluxes from C. malaccensis marsh was decreased by tread, and the reducing range was relevant to seasons and changes of environment factors resulting from flood and ebb.
human-caused disturbancenitrous oxide fluxnutrient inputMinjiang River estuary
NETL
NSTL
万方数据
