Abstract Recent studies showed great variations in both soil inorganic carbon (SIC) and organic carbon (SOC) in cropland across the North China Plain. This work was designed to test the hypothesis that hydrological processes associated with the Yellow River may be responsible for the differences in soil carbon dynamics over space. We selected 22 sites from the wheat-maize cropland across the Yellow River in the south North China Plain, and measured SOC, SIC, water-extractable organic carbon (WEOC) and other soil properties over 0–20, 20–40, 40–60, 60–80 and 80−100 cm. Our results showed that SOC and SIC stocks were 5.82 ± 1.26 kg C m−2 and 13.7 ± 8.50 kg C m−2 in the 0−100 cm, respectively. SIC stock showed a positive correlation with SOC stock (P 7.8 soils. SOC content was lower (1.67-1.78 g kg-1), but WEOC:SOC ratio (4.45–5.18 %) was higher over 60−100 cm in the Fluvo-aquic soils near the Yellow River. Our findings indicated that low SOC content near the Yellow River may reflect weak protection of SOC, which was probably linked to hydrological processes and soil characteristics such as sand and SIC contents.

中文翻译：

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华北平原农田土壤性质和水文过程对土壤碳动态的影响

摘要 最近的研究表明，华北平原农田土壤无机碳（SIC）和有机碳（SOC）变化很大。这项工作旨在检验与黄河相关的水文过程可能是造成土壤碳动态在空间上的差异的假设。我们从华北平原南部横跨黄河的小麦-玉米农田中选取了 22 个样点，测量了 0-20、20-40、40-的 SOC、SIC、水溶有机碳（WEOC）等土壤性质。 60、60-80 和 80-100 厘米。我们的结果表明，在 0-100 cm 范围内，SOC 和 SIC 储量分别为 5.82 ± 1.26 kg C m-2 和 13.7 ± 8.50 kg C m-2。SIC 储量与 SOC 储量呈正相关（P 7.8 土壤。SOC 含量较低（1.67-1.78 g kg-1），但 WEOC:SOC 比率（4.45-5. 18 %) 在黄河附近的潮土土壤中高于 60-100 cm。我们的研究结果表明，黄河附近的 SOC 含量低可能反映了对 SOC 的保护较弱，这可能与水文过程和土壤特性（如沙子和 SIC 含量）有关。