Cover crop (CC) decomposition and subsequent release of nitrogen (N) are highly influenced by residue water potential (ψ) and temperature (T). To evaluate how carbon (C) and N mineralization from surface-applied CC residues responds to changes in ψ and T, a controlled microcosm experiment was conducted for 150 days with three CC residues (early-killed cereal rye (Secale cereale L.), late-killed cereal rye, late-killed crimson clover (Trifolium incarnatum L.), and a soil-alone control) under different ψ (−0.03, −1.5, −5, and −10 MPa) and T (15, 25, and 35 °C) conditions. Headspace gas was sampled periodically to determine carbon dioxide (CO₂) and nitrous oxide (N₂O) emissions. Soil inorganic N was determined by destructive sampling at 15, 30, 60, 100, and 150 days. Temporal dynamics in C and N mineralization from surface-applied CC residues were adequately described by first-order rate kinetic models. Early-killed rye and crimson clover (low C:N) residues decomposed quickly and mineralized N, whereas, late-killed rye residue (high fiber content and C:N) immobilized N. The normalized values of C and N mineralized from surface-applied CC residues increased exponentially with increasing ψ from −10.0 to −0.03 MPa. Increasing T from 15 to 35 °C further amplified the effect of ψ, suggesting a strong interactive effect of ψ and T on C and N mineralization from CC residues. Mathematical equations were developed to describe these interactive effects. Existing computer simulation models (e.g., CERES-N) could be improved by integrating these equations to simulate the effect of environmental conditions on surface-applied CC residue decomposition and N mineralization.

残留作物水势（ψ）和温度（T）对覆盖作物（CC）的分解和随后释放的氮（N）产生很大影响。为了评估表面施用CC残留物中碳（C）和N矿化如何响应ψ和T的变化，我们对三种CC残留物（早熟谷类黑麦（Secale graine L.））进行了150天的受控微观实验，在ψ（-0.03，-1.5，-5和-10 MPa）和T分别不同的条件下，晚熟谷物黑麦，晚熟深红色三叶草（Trifolium incarnatum L.）和土壤单独对照）（15、25和35°C）条件下。定期采样顶空气体，以确定二氧化碳（CO ₂）和一氧化二氮（N ₂ O）的排放量。在15、30、60、100和150天通过破坏性采样确定土壤无机氮。通过一级速率动力学模型充分描述了表面施用CC残留物中碳和氮矿化的时间动态。早期杀死的黑麦和深红色三叶草（低C：N）残留物迅速分解并矿化N，而晚期杀死的黑麦残留物（高纤维含量和C：N）固定N。从表面矿化的C和N归一化值施加的CC残留量随ψ从-10.0到-0.03 MPa呈指数增加。T增加在15至35°C的温度下，ψ的作用进一步增强，表明ψ和T对CC残留物中C和N矿化的强烈相互作用。开发了数学方程式来描述这些交互作用。通过集成这些方程来模拟环境条件对表面施加的CC残留物分解和N矿化的影响，可以改善现有的计算机模拟模型（例如CERES-N）。