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13 7Cs示踪技术目前已被广泛用于长期的土壤侵蚀 (水蚀 )估算。该技术要解决的两个关键问题是土壤13 7Cs基准值的确定 ,以及土壤的13 7Cs损失量与土壤侵蚀量之间的定量模型的建立。对现有的主要的定量模型进行了简述 ,并提出了各自的局限性。这些模型可分为经验模型和理论模型两大类 ,其中以理论模型中的质量平衡模型较为成熟 ,综合考虑了较多的侵蚀因子 ,如13 7Cs年沉降分量、土壤颗粒粒径分布差异、地表富集作用、耕作土壤在耕作活动前新沉降13 7Cs的侵蚀损失等。对现有模型的改进也进行了探讨 ,并提出了今后的一些研究重点。
13 7Cs tracer technology is now widely used for long-term soil erosion (water erosion) estimation. The two key issues to be addressed by this technique are the determination of the baseline value of 13 7 Cs in soil and the establishment of a quantitative model of soil loss from 13 7 Cs and soil erosion. The existing major quantitative models are briefly described and their respective limitations are proposed. These models can be divided into two major categories: empirical model and theoretical model. Among them, the model of mass balance in the theoretical model is relatively mature, and more factors of erosion are comprehensively considered. For example, the sedimentation component of 137Cs, the distribution of soil particle size, Enrichment, erosion loss of newly-settled 13 7Cs before tillage activities in tillage soils. The improvement of the existing model is also discussed, and some future research focuses are put forward.