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本文在全面阐述 1 37Cs法技术原理的基础上 ,选择青海共和盆地作为研究区 ,探讨 1 37Cs法在土壤风蚀研究中应用的可行性。通过野外考察和大量 1 37Cs取样分析 ,初步查明了共和盆地 1 37Cs的区域和剖面分布特征 ,确定了区域 1 37Cs背景值 ,建立了风蚀速率的 1 37Cs评估模型 ,估算出土壤风蚀速率 ,并结合近 40年来区域环境变化的背景资料 ,综合分析现代风蚀过程及其与环境变化的关系。初步得出以下结果 :1.通过对共和盆地不同类型土壤剖面的 1 37Cs取样分析 ,基本查清了区域 1 37Cs分布的若干特性 ,分析了一些典型剖面的 1 37Cs深度分布及其机制。据测定 ,共和盆地 1 37Cs活度平均值为 (4.84± 0 .34 ) Bq· kg- 1 ,1 37Cs总量平均值为 (15 13.83± 10 8.37) Bq· m- 2。不同类型土地 1 37Cs活度的排序为 :林地 >干湖盆 >高寒草原 >旱作农田≈干草原 >固定沙丘 >荒漠草原 >流动沙丘 >风蚀地 ,1 37Cs总量的排序为 :干湖盆 >林地 >流动沙丘 >高寒草原 >旱作农田≈干草原 >固定沙丘 >荒漠草原 >风蚀地。2 .在所测 1 37Cs样品中 ,以沙丘砂的 1 37Cs含量最为典型 ,主要表现在 :一是含量小 ,平均值为 (1.6 3± 0 .15 ) Bq·kg- 1 ,接近 1 37Cs探测的最低下限 ;二是含量均匀 ,无论在区域上 ,还是在剖面分布上 ,大
Based on a comprehensive exposition of the technical principles of the 1 37Cs method, this paper chooses the Qinghai Gonghe Basin as a research area to investigate the feasibility of the application of the 1 37Cs method in soil erosion research. Through the field investigation and large amount of 1 37Cs sampling and analysis, the regional and section distribution characteristics of 1 37Cs in the Gonghe Basin were preliminarily identified, and the background value of 1 37Cs in the area was determined. The 1 37Cs assessment model of wind erosion rate was established to estimate the soil erosion rate. Combining with the background information of regional environmental change in the recent 40 years, a comprehensive analysis of the modern wind erosion process and its relationship with environmental changes is made. Preliminary results are as follows: 1. Based on the sampling and analysis of 1 37Cs in different types of soil profiles in the Gonghe Basin, some characteristics of the 1 37Cs distribution in the area were basically ascertained, and the depth distribution of 1 37Cs and its mechanism in some typical sections were analyzed. According to the determination, the average activity of 1 37Cs in the Gonghe basin was (4.84 ± 0.34) Bq · kg -1, and the average value of 1 37Cs was (15 13.83 ± 10 8.37) Bq · m -2. The order of activity of 1 37Cs in different types of land is as follows: forest land> dry lake> alpine steppe> dry farmland ≈ dry grassland> fixed sand dune> desert steppe> mobile dune> > Woodland> Mobile dunes> Alpine steppe> Dry farmland ≈ Steppes> Fixed dunes> Desert steppe> Wind erosion. The content of 1 37Cs in dune sand is the most typical among the 1 37Cs samples tested, mainly including: the content is small, the average is (1.6 3 ± 0.15) Bq · kg -1, which is close to the detection of 1 37Cs The minimum limit; Second, the content is uniform, both in the region, or in the profile distribution, large