Denitrification removes reactive nitrogen (N) from ecosystems by transforming nitrate (NO₃⁻) to dinitrogen (N₂) gas. Incomplete denitrification produces nitrous oxide (N₂O), a potent greenhouse gas. In salt marshes, denitrification, N₂O production, and N₂O yield (the fraction of denitrification that produces N₂O) have implications for N load reduction and greenhouse gas emissions. We collected soil cores from three salt marsh zones (low marsh, high marsh, and invasive Phragmites australis) on five sampling dates that spanned the growing season (May through October) to quantify seasonal patterns of potential denitrification, N₂O production, and N₂O yield. Potential denitrification peaked at the beginning and end of the growing season, with rates several times higher in May and October than in June, but we found no significant differences among salt marsh zones. In contrast, seasonal patterns of potential N₂O production depended on marsh zone; N₂O production was aseasonal in high marsh and P. australis zones, but in the low marsh, N₂O production was lower in July compared to all other months sampled. In this salt marsh, seasonal variation of potential denitrification and N₂O production was greater than spatial variation over the marsh zones, highlighting the importance of understanding temporal patterns of salt marsh N cycling.

（NO脱氮通过变换硝酸盐去除从生态系统中活性氮（N）₃ ^- ），以二氮（N ₂）气体。反硝化作用不完全会产生一氧化二氮（N ₂ O），这是一种有力的温室气体。在盐沼中，反硝化作用，N ₂ O的产生和N ₂ O产量（产生N ₂ O的反硝化的比例）对减少氮负荷和温室气体排放都有影响。我们在整个生长季节（5月至10月）的五个采样日期收集了三个盐沼地区（低沼泽，高沼泽和侵入性芦苇）的土壤核心，以量化潜在反硝化的季节性模式N ₂O的产生和N ₂ O的产率。潜在的反硝化作用在生长季节的开始和结束时达到顶峰，5月和10月的反硝化率比6月高出几倍，但我们发现盐沼地区之间没有显着差异。相反，潜在的N ₂ O产生的季节模式取决于沼泽地带。N ₂ O的生产在高沼泽地带和P. australis地区是反季节的，但在低沼泽地带，与所有其他采样月份相比，7月份N ₂ O的生产量要低。在该盐沼中，潜在反硝化和N _2的季节变化O的产生大于沼泽地带的空间变化，突显了理解盐沼N循环时空模式的重要性。