Measuring in situ soil fluxes of carbon dioxide ( COsub2/sub ), methane ( CHsub4/sub ), and nitrous oxide ( Nsub2/subO ) continuously at high frequency requires appropriate technology. We tested the combination of a commercial automated soil COsub2/sub flux chamber system (LI-8100A) with a CHsub4/sub and Nsub2/subO analyzer (Picarro G2308) in a tropical rainforest for 4?months. A chamber closure time of 2?min was sufficient for a reliable estimation of COsub2/sub and CHsub4/sub fluxes (100?% and 98.5?% of fluxes were above minimum detectable flux – MDF, respectively). This closure time was generally not suitable for a reliable estimation of the low Nsub2/subO fluxes in this ecosystem but was sufficient for detecting rare major peak events. A closure time of 25?min was more appropriate for reliable estimation of most Nsub2/subO fluxes (85.6?% of measured fluxes are above MDF ± 0.002?nmol?m sup?2/sup s sup?1/sup ). Our study highlights the importance of adjusted closure time for each gas.
展开▼
