7^Be在示踪土壤侵蚀和沉积物中的研究探讨  

Study on Application on Fallout Beryllium-7 as a Tracer in Soil Erosion and Sediment

作　　者：高明[1] 杨浩[1] 刘磊[1] 唐敏[1] 

机构地区：[1]南京师范大学地理科学学院,南京210097

出　　处：《水土保持研究》2006年第5期282-285,287,共5页Research of Soil and Water Conservation

基　　金：国家自然科学基金重点项目(40473052)

摘　　要：环境放射性核素137Cs和210Pb为测量土壤侵蚀和沉积速率提供了一种重要的方法。然而这两种核素只能提供中长期(45年和100年)的土壤再分配的速率,因此有必要研究示踪个别事件或短周期的土壤再分配的速率作为示踪中长期土壤再分配速率的有益补充,7Be(半衰期53.3 d)作为自然放射性核素,能够满足示踪个别事件或短周期的土壤再分配的需要,越来越受到广泛的关注。土壤再分配过程一般是自然和人为因素共同引起的,需要评价他们各自对土壤再分配过程的影响程度,用于评价土地利用和水土保持措施的效果,更为重要的是用于土地资源可持续利用和环境保护。讨论了7Be产生规律以及沉降特点,阐述了7Be在土壤再分配过程中的示踪原理,并对现有土壤侵蚀定量估算模型进行阐述并改进了模型,提出了今后应用7Be技术的研究方向。：The environmental radionuclides 137^ Cs and 210^ Pb for documenting soil erosion and sendiment rates provide an important method. However, measurements of these radlonuclides provide estimates of medium-term soil redistribution rates and there is a need to use complementary radionuclides to estimate redistribution rates associated with individual events or short-term. Beryllium=7（t0.5 =53.3 days）,as natural radionuclide,can fulfill requirements. Natural and man-made activities processes arose soil redistribution. The authors assess their influences on redistribution, respectively, and evaluate effection on land use and water and soil conservation,more important for sustainable land use and environment protection. The fallout 7^ Be, principles and hypothesises on tracer in soil redistribution are discussesd. The existing quantitative models for soil erosion estimate using tracer technology was reviewed and advancing an improved model. Lastly, the environmental radionuclides ratios may be better advanced.

关 键 词：土壤再分配 7^Be 示踪原理 

分 类 号：S157[农业科学—土壤学]