Soil respiration is a primary component of the terrestrial carbon cycle. However, predicting the response of soil respiration to climate change remains a challenge due to the complex interactions between environmental drivers, especially plant phenology, temperature, and soil moisture. In this study, we use a 1‐D diffusion‐reaction model to calculate depth‐resolved CO₂ production rates from soil CO₂ concentrations and surface efflux observations in a subalpine meadow in the East River watershed, CO. Modeled rates are compared to in situ soil temperature and moisture conditions and MODIS satellite enhanced vegetation index (EVI) representing plant phenology across three hydrologically distinct growing seasons from 2016–2018. While soil respiration correlated with temperature on diel timescales (p < 0.05), seasonal variability was dominated by soil moisture and plant phenology (p < 0.05). We observed significant respiration increases in response to precipitation events; however, magnitude and duration were significantly higher in 2017 than 2016 despite similar wetting characteristics. Based on MODIS EVI, we suggest that the respiration response to rainfall is controlled by plant phenology, which in turn reflects the capacity of plants to respond to precipitation via increased photosynthesis and autotrophic respiration, behavior that is not captured in typical soil respiration pulse models. Projected changes in montane climate such as earlier snowmelt and prolonged fore‐summer drought may decrease soil respiration fluxes by decreasing the overlap between peak productivity and the summer monsoon. Finally, we observed significant late season CO₂ fluxes from the deep subsoil (>165 cm) that support growing evidence for the importance of subsoil processes in driving integrated respiration fluxes.

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在美国科罗拉多州东河的山地草地上，植物物候学对降雨对土壤呼吸的响应

土壤呼吸是地球碳循环的主要组成部分。然而，由于环境驱动因素之间的复杂相互作用，尤其是植物物候，温度和土壤湿度之间的相互作用，预测土壤呼吸对气候变化的响应仍然是一个挑战。在这项研究中，我们使用一维扩散反应模型从土壤CO _2中计算深度分辨的CO ₂生产率。密歇根州东河流域亚高山草甸的水浓度和表面外排观测。将模型化速率与原地土壤温度和湿度条件以及MODIS卫星增强植被指数（EVI）进行了比较，这些指数代表了自2016年以来三个水文不同生长期的植物物候2018。虽然土壤呼吸与温度在diel时间尺度上相关（p  <0.05），但季节变化主要由土壤水分和植物物候（p <0.05）。我们观察到响应降水事件的呼吸显着增加。然而，尽管具有类似的润湿特性，2017年的强度和持续时间仍显着高于2016年。基于MODIS EVI，我们建议通过植物物候控制降雨对呼吸的响应，这反过来又反映了植物通过增加光合作用和自养呼吸来响应降水的能力，这在典型的土壤呼吸脉冲模型中是无法捕获的。预计山地气候的变化，例如较早的融雪和长期的前夏干旱，可能会通过减少峰值生产力和夏季风之间的重叠来减少土壤呼吸通量。最后，我们观察到明显的后期CO ₂ 来自深层土壤（> 165厘米）的通量，这为越来越多的证据表明了地下土壤过程在驱动综合呼吸通量中的重要性。