Interest in novel perennial grain crops has increased as a sustainable alternative to conventional annual grain crops due to their improved carbon (C) sequestration and water use efficiency potentials. This study quantified carbon dioxide (CO₂) and water fluxes over contrasting cropping systems: a perennial crop (i.e., Secale cereale L. × S. montanum Guss cv. ACE-1 perennial rye) vs. an annual crop (i.e., S. cereale L. cv. Gazelle spring rye). The experiment was conducted over two growing seasons (May to October) using eddy covariance system measurements in two adjacent 4-ha fields in Breton, Alberta, Canada. Substantially greater uptake of atmospheric C was observed in the perennial crop compared to the annual crop, as shown by growing season net ecosystem CO₂ exchange of 556 g C m⁻² yr⁻¹ in the perennial crop vs. only 89 g C m⁻² yr⁻¹ in the annual crops. Net ecosystems carbon balances (NECB) of -60 and 448 g C m⁻² were either C neutral or C gain in perennial crops, while NECB of -263 and -336 g C m⁻² in annual crops were C losses during the two growing seasons. Overall, the ecosystem carbon use efficiency of the perennial crop was also greater than that of the annual crops. In addition to the longer growing period of the perennial crop, which enhanced the cumulative C captured via photosynthesis, the greater CO₂ sink was attributed to relatively lower ecosystem respiration, which was influenced by soil temperature sensitivity, reduced soil disturbance, and soil moisture factors. Despite the perennial crop registering higher evapotranspiration (ET) at the beginning of growing season, the overall cumulative ET and the associated ecosystems-water use efficiency were similar between the two crops. As such, the perennial crop enhanced atmospheric CO₂ sink compared to annual crop, whereas the terrestrial water balance was similar between two crops.

新型多年生粮食作物作为传统一年生粮食作物的可持续替代品，由于其碳 (C) 固存和水利用效率潜力得到改善，因此受到越来越多的关注。本研究定量二氧化碳（CO ₂）和水通量超过对比耕作系统：一种多年生作物（即，黑麦L. ×S. montanum摊铺CV ACE-1多年生黑麦。）对一个一年生作物（即，S.谷物L.简历 瞪羚春黑麦）。该实验是在加拿大艾伯塔省布列塔尼的两个相邻 4 公顷田地中使用涡流协方差系统测量在两个生长季节（5 月至 10 月）进行的。与一年生作物相比，观察到多年生作物对大气碳的吸收显着更多，如生长季节净生态系统 CO ₂交换在多年生作物中的 556 g C m ^-2 yr ^-1与仅 89 g C m ^{- 所示。}一年生作物²年^-1年。-60 和 448 g C m ^{-2 的}净生态系统碳平衡 (NECB) 是多年生作物的碳中性或碳增加，而 NECB 为 -263 和 -336 g C m ^-2一年生作物的碳损失在两个生长季节。总体而言，多年生作物的生态系统碳利用效率也高于一年生作物。除了多年生作物较长的生长期增加了通过光合作用捕获的累积碳外，较大的 CO ₂汇归因于相对较低的生态系统呼吸，这受到土壤温度敏感性、土壤干扰减少和土壤水分因素的影响. 尽管多年生作物在生长季节开始时记录了较高的蒸散量 (ET)，但两种作物之间的总体累积 ET 和相关的生态系统水利用效率相似。因此，多年生作物增强了大气 CO ₂ 与一年生作物相比下沉，而两种作物之间的陆地水平衡相似。