资源环境科技发展态势分析平台

Methane (CH₄) and nitrous oxide (N₂O) dynamics in coastal coral reef areas are poorly understood. We measured dissolved carbon dioxide (CO₂), and CH₄ (with δ¹³C-CO₂ and δ¹³C-CH₄ isotope fractions) and N₂O in the Great Barrier Reef (GBR) to determine spatial distributions and emissions. CO₂ (379-589μatm) was oversaturated from calcification and riverine sources, as indicated by depleted δ¹³C-CO₂ values. CH₄ (1.5-13.5nM) was also oversaturated from nearshore biogenic sources indicated by depleted δ¹³C-CH₄ and probable offshore aerobic production . N₂O (5.5-6.6nM) was generally undersaturated, with uptake highest near the coast. Daily CO₂ emissions were 5826 ±1191 tonnes, with CO₂ equivalent (_eq) N₂O uptake (191 ±44 tonnes) offsetting 3.3% of CO₂ or 89% of CH_4eq (214 ±45 tonnes) emissions based on 20-year global warming potentials. The GBR was a slight CO₂ and CH₄ source and N₂O sink during our study. However, further work is required to constrain diurnal, seasonal, and spatial dynamics.