黑土区典型小流域不同时空尺度的泥沙来源研究

项目名称： 黑土区典型小流域不同时空尺度的泥沙来源研究

项目编号： No.41501299

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 地质学

项目作者： 杜鹏飞

作者单位： 中国水利水电科学研究院

项目金额： 20万元

中文摘要： 泥沙来源研究对流域泥沙平衡计算、河流泥沙减控、土壤侵蚀预报模型验证和水土保持效益评价都具有非常重要的意义，是土壤侵蚀和泥沙输移研究的重点与热点问题之一。本项目以东北黑土区典型小流域为研究对象，拟建立潜在侵蚀物源和“指纹”因子间的联系，提出反映潜在物源代表性样品的采集方法；通过“指纹识别”技术，分析子流域尺度上次洪水事件不同产沙源地的侵蚀贡献比和泥沙沿程输移特点；结合放射性元素Cs-137和Pb-210测年技术，建立子流域和小流域空间尺度上不同物源泥沙的空间输移沉积关系，研究中等时间尺度（10-100年）上泥沙来源的动态变化。研究成果对推广应用“指纹识别”方法和揭示东北黑土区典型小流域泥沙输移规律有重要意义，对该区生态建设与保护由“事后治理”向“事前预防”的战略性转变具有指导价值。

中文关键词： 泥沙来源；指纹识别；核素示踪；黑土区；时空对比

英文摘要： Sediment source study is valuable for watershed sediment budget, sediment control in channels, soil erosion model validation and benefits evaluation of soil and water conservation, and hence become one of the key and hot spots. Take a typical watershed located in the northeast black soil region of China as study area, the specific objective for this study as follows: (1) to propose efficient and effective sampling strategies through linking sediment source and fingerprint properties by collection and analysis of a number of samples in sub-watershed; (2) to analyze sedimentation characteristics and sediment sources in flood scale and medium time (10-100 yrs) scale; (3) to make clear the dynamic change of sediment source in different spatial scales (sub-watershed and watershed) in past several decades through estimating sedimentation rate using radionuclides 137Cs and 210Pb. This study is meaningful in application of fingerprint technique and in revealing of transportation and sedimentation mechanism in typical watershed of northeast black soil region, and will provide valuable reference for ecological protection strategy change from treatment to prevention.

英文关键词： sediment source;fingerprinting;radiounclides tracing;black soil region;comparison of different temporal and spacial scales