川中丘陵区小流域产沙量与泥沙来源-塘库沉积调查与~(137)Cs示踪研究
文献类型：学位论文
| 作者 | 伏介雄 |
| 学位类别 | 硕士 |
| 答辩日期 | 2005 |
| 授予单位 | 中国科学院研究生院 |
| 授予地点 | 北京 |
| 导师 | 张信宝 |
| 关键词 | 塘库调查 ~(137)Cs含量 产沙量 相对产沙量 小流域 川中丘陵区 |
| 其他题名 | Sediment Yields and Sediment Sources of Small Catchments in the Hilly Sichuan Basin - by Using Pond and Reservoir Deposits and ~(137)Cs Technique |
| 学位专业 | 自然地理学 |
| 中文摘要 | 水土流失是中国头号环境问题。历次土壤侵蚀调查，均认为川中丘陵区是土壤侵蚀严重的地区。景可和张信宝等人，对用0．1左右的低泥沙输移比来解释该区3000-5000t·km~(-2)·a~(-1)的侵蚀模数与该区200-1000t·km~(-2)·a~(-1)的河流悬移质输沙模数的巨大差异提出了置疑。可靠的侵蚀模数及泥沙来源，对川中丘陵区土壤侵蚀和塘库来沙变化趋势的正确预测，水土保持方略及流域土地利用政策的制定，无疑具有重要的意义。传统的侵蚀研究方法需要大量资金和长期观测，都存在一定的局限性。~(137)Cs是土壤侵蚀研究的一种良好示踪源，在土壤侵蚀研究中~(137)Cs法已经取得了丰硕成果，但通过塘库沉积泥沙调查及结合~(137)Cs技术研究流域产沙的研究极少。论文以川中丘陵区流溪河小流域为例，运用塘库沉积泥沙调查和~(137)Cs示踪技术分析了流溪河小流域产沙量及其相对产沙量。主要研究结论如下：（1）利用~(137)Cs示踪法研究表明：天马湾流域1954-1963年期间的平均沉积速率、输沙模数分别为6.7·a~(-1)、2524t·km~(-2)·a~(-1)；1963-1981年期间的平均沉积速率、输沙模数分别为1.4cma-1、526t．km-2·a~(-1)；1954-1981年以来的平均沉积速率、平均输沙模数分别为3.15cm·a~(-1)、1192t·km~(-2)·a~(-1)。（2）天马湾塘库上游谷地内两个水稻田土壤剖面137cs深度分布表明，水稻田内基本无淤积；野外调查表明，塘库以上的其他谷地内无明显泥沙沉积。塘库上游流域的平均侵蚀速率可以认为接近于输沙模数，1954-1981年以来天马湾流域的平均输沙模数1192t·km~(-2)·a~(-1)远低于3000-5000t·km~(-2)·a~(-1)。（3）野外调查研究表明，水库和山湾塘上游来沙基本拦蓄于库内，调查所得流溪河水库和山湾塘的平均淤沙模数762t·km~(-2)·a~(-1)，可以代表当地小流域的输沙模数；流溪河小流域不同流域面积山湾塘和水库的淤沙模数差异不大，淤沙模数随流域面积增大而减少的趋势很不明显，~(137)Cs法研究也表明水稻田及塘库以上的其他谷地内无明显泥沙沉积，泥沙输移比应远大于前人报导的0.1-0.27。即使考虑一定的泥沙输移比，若用景可认为的丘陵宽谷区泥沙输移比最小值0.5，南充李子溪流域的侵蚀模数也应远低于3000t·km~(-2)·a~(-1)。（4）曹湖沟塘库泥沙~(137)Cs含量2.4±0.22Bq·kg~(-1)，低于农耕地耕作土~(137)Cs含量3.7±0.29Bq·kg~(-1)。流域内农耕地为泥沙的最主要来源，但裸坡和沟岸也是主要来源。 |
| 英文摘要 | Soil and Water Loss is the first important environmental problem in China. It was believe that the Hilly Sichuan Basin was one of the most severe soil erosion areas in China by every state soil erosion surveys using the remote sensing technique. Jing Ke and Zhang Xinbao et al. doubted that sediment delivery ratios of about 0.1 to explain the most diference between erosion yields of 3000-5000t·km~(-2)·a~(-1) and river specific sediment yield of 200- 1000t·km~(-2)·a~(-1) in the Hilly Sichuan Basin. Reliable sediment yields and sediment sources are very important to evaluate the change tendency of soil erosion and the inflow condition of pond and reservoir and to make implement improved land management policies and conservation strategies. Traditional methods on monitor soil erosion have some limitations in bill and time. The Cs technipue is now widely applied in soil erosion researches, because of its easy operation, low costs and high reliabity. However, few publications be consulted about sediment yields and sediment sources of small catchments by using pond and reservoir deposits and ~7Cs technique. Based on the analysis of several confused definitive and count way of soil erosion by many people, this thesis comprehensively introduced the progress of sediment yields and sediment sources in the Hilly Sichuan Basin. Taking a small catchment, Liuxi River, in the Hilly Sichuan Basin of China as a sample, sediment yields and sediment sources was analyed by using pond and reservoir deposits and ~(137)Cs technique. The main conclusions are as follows: 1. ~(137)Cs technique study showed that the mean deposits rate and the mean specific sediment yield in Tianma Gully were 6.7cm·a~(-1) and 2524t·km~(-2)·a~(-1) from 1954 to 1963, t·km~(-2)·a~(-1) and 526t·km~(-2)·a~(-1) from 1963 to 1981, and 3.15 cm-a"1 and 1192t·km~(-2)·a~(-1) from 1954 to 1981. 2. Two profiles of ~(137)Cs of two paddy fields over the catchment above the reservoir show that there are no deposits in paddy fields. Field investigation indicated that no significant deposition occurred in the other gully bottom upstream of the pand and reservoir. The average erosion rate over the catchment above the reservoir was suggested to be close to the specific sediment yield. The soil erosion rate of 1192t·km~(-2)·a~(-1) in the Tianma Gully from 1954 to 1981 should be much less than the values of 3000-5000 t-km'V1. 3. Field investigation indicated that inflow sediment over the catchment above the reservoir and Shanwan pond was trapped in the pond and reservoir. The difference of depositis yields is not apparent of different catchment areas Shanwan pond and reservoir in the Liuxi River catchemet. The tendency of sediment yield increase with catchment area increase is not apparent. ~(137)Cs technique study showed that paddy field and other gully bottom upstream of the pond and reservoir is not apparent sediment depositis, the sediment delivery ratio in the basin should be much higher than the reported values of 0.1-0.27. Using soil erosion rate of 0.5 reported by Jing Ke, the soil erosion rate of Nanchong Liuxi River should be much less than the values of 3000-5000t·km~(-2)·a~(-1). 4. 137Cs content of the deposited sediments in the pond of Caohu Gully is 2.4±0.22 Bq·kg~(-1). It is lower than I37Cs content of the cultivated terraces of Caohu Gully, which is 3.7±0.29Bq-kg'1. Cultivated terrace was the first important sediment source in catchment. However, bare slopes and channel banks were important sediment sources in catchment. |
| 语种 | 中文 |
| 公开日期 | 2013-08-22 |
| 源URL | [http://ir.imde.ac.cn/handle/131551/6221]  |
| 专题 | 成都山地灾害与环境研究所_成都山地所知识仓储（2009年以前） |
| 推荐引用方式 GB/T 7714 | 伏介雄. 川中丘陵区小流域产沙量与泥沙来源-塘库沉积调查与~(137)Cs示踪研究[D]. 北京. 中国科学院研究生院. 2005. |
入库方式： OAI收割
来源：成都山地灾害与环境研究所
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