| 摘要: |
| 【 目的】研究冻融条件下坡面水沙过程和速效氮磷流失规律，以揭示两者之间的时滞效应，为坡面水土-养分流失防治提供重要的参考依据。【 方法】通过室内模拟降雨和冻融试验，分析不同初始含水量条件下未冻融 （LS）和冻融（FTS）坡面径流和泥沙中速效氮（AN）和速效磷（AP）的迁移规律及流失途径，阐明冻融作用下坡面水沙 过程与速效氮磷流失的时滞效应。【 结果】冻融作用明显延长了坡面达到稳定入渗所需的时间，影响了坡面产流产沙过程。当初始含水量为30%时，冻融坡面总产流量最大，但是总产沙量相对较小。两种处理坡面下AN和AP随径流 和泥沙的流失比例在不同初始含水量下具有明显差异，但是主要流失途径均以径流为主。未冻融坡面AN流失与产流量保持同步；而在冻融坡面，当初始含水量为10%时，AN流失与产流过程存在45 min的滞后；当初始含水量为30%时，滞后时间缩短至30 min。【 结论】冻融作用改变了坡面速效氮磷迁移与产流过程的时滞效应，对速效磷流失与产沙过程的响应影响不显著。 |
| 关键词: 坡面水沙过程 有效氮 有效磷 冻融作用 时滞效应 黄土高原 |
| DOI：10. 13207/j. jnwafu. 2026. 11. 016 |
| 分类号: |
| 基金项目:国家自然科学基金项目（42167007） |
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| Time⁃lag effect of runoff⁃sediment process and available nitrogen and phosphorus loss under freeze⁃thaw conditions |
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CHENG Yuting1, WANG Ziyang1, ZHANG Yi1, HAO Shuhao2, LI Peng2, XU Guoce2, DANG Xiaohu1
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1.College of Geology and Environment，Xi'an University of Science and Technology，Xi’an，Shannxi 710054，China;2.School of Water Resources and hydro-electric Engineering，Xi'an University of Technology，Xi’an，Shaanxi 710048，China
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| Abstract: |
| 【 Objective】This research aims to investigate the slope runoff-sediment processes and the patterns of available nitrogen（AN） and phosphorus（AP） loss under freeze-thaw conditions，in order to reveal the time-lag effect between them，and to provide an important reference for soil and water conservation and prevention of nutrient loss during the freeze-thaw period on the Loess Plateau.【Method】Indoor simulated rainfall and freeze-thaw experiments were conducted to analyze the migration patterns and loss pathways of AN and AP in runoff and sediment under different initial water content conditions for two slope treatments：unfrozen-thawed slope（LS） and frozen-thawed slope（FTS）.And the time-lag effect between slope runoff-sediment processes and available nitrogen-phosphorus loss under freeze-thaw was clarified.【Result】Freeze-thaw significantly pro-longed the time required for the slope to reach stable infiltration and affected the slope runoff and sediment yield processes. When the water content was 30%，the total runoff of FTS slope was the highest，but the total sedi?ment yield was relatively low. Under different water content conditions，significant difference was observed in the ratios of AN and AP lost via runoff and sediment in LS and FTS treatments，with the runoff being the main loss pathway in both cases. Freeze-thaw altered the time-lag effect between available nitrogen migration and run-off processes on slopes. AN loss in LS slope occurred synchronically with runoff，while in FTS slope，there was a 45-minute lag between AN loss and runoff processes under the water content condition of 10%. And the lag time was shortened to 30 minutes under the water content condition of 30%.【Conclusion】Freeze-thaw altered the time-lag effect between the migration of available nitrogen and phosphorus on slopes and the runoff generation process，but showed no significant effect on that between available phosphorus loss and the sediment yield process. |
| Key words: slope runoff-sediment process available nitrogen available phosphorus freeze-thaw action time-lag effect Loess Plateau |
