CHEN Rui-ting,ZHANG Ming-li,YANG Hao.Dynamic Equilibrium Model of 210Pbex Background Value in Soil[J].Research of Soil and Water Conservation,2013,20(05):73-76.
土壤中210Pbex背景值含量动态平衡模型
- Title:
- Dynamic Equilibrium Model of 210Pbex Background Value in Soil
- 关键词:
- 210Pbex背景值; 大气沉降量; 年降水量
- 分类号:
- S157.1
- 摘要:
- 在利用土壤侵蚀模型估算侵蚀速率的过程中，背景值点选取的好坏直接关系到结论是否可靠，如果能通过科学计算得出研究区域背景值，将大大提高背景值的准确性，对研究土壤侵蚀具有重大意义。土壤未受到侵蚀和沉积的背景区，首先假设全球大气沉降量为定值，研究把210Pbex沉降过程以一年为时间尺度划分为n年，经过n年以后（n=0，1，2，…，∞），土壤中210Pbex沉降量和经过衰变减少量达到平衡，土壤中210Pbex含量趋于稳定。假设各地年平均降水量为定值，通过研究发现210Pbex的大气沉降通量与年降水量之间存在极显著相关（P < 0.01），区域年降水量是影响土壤中210Pbex量的主要因素，由于年平均降水量不同，全球各地土壤中210Pbex含量都会达到不同的稳定值，从而建立土壤中210Pbex含量与年降水量关系模型。研究210Pbex来源、沉降的连续性和稳定性，提出利用区域年平均降水量来计算该地区的210Pbex背景值，建立土壤中210Pbex背景值含量动态平衡模型，为准确确定210Pbex背景值提供了方法，对研究土壤侵蚀具有重要的意义。
- Abstract:
- Selection of background value point is directly related to the conclusion that is reliable or not in the process of estimating erosion rate by use of soil erosion model. If the background value can be calculated through scientific research, which will greatly improve the accuracy of the background value and is great significance of soil erosion study. In the background region, the soil is not affected by erosion and deposition, assuming that the atmospheric precipitation amount setting value. Based on the time scale of 210Pbex sedimentation process for one year time scale, after n years later, the soil 210Pbex settlement and the amount of 210Pbex decay decrement achieve balance in this study. It is assumed that an average annual rainfall is constant in various regions. Research finds that correlation between 210Pbex atmospheric subsidence flux and annual rainfall is extremely significant correlation(p<0.01). Regional annual precipitation becomes main factors affecting the amount of soil 210Pbex. Because the annual rainfall is different around the world, the 210Pbex content can reach the stability of the different values, so as to establish relationship model with annual precipitation 210Pbex content in the soil. According to the 210Pbex settlement continuity and stability, this research put forward to calculate the area of 210Pbex background value through the regional average annual precipitation. According to the establishment of the soil 210Pbex background value content dynamic equilibrium model, it provides a method of accurately determining 210Pbex background value and has an important significance to regional soil erosion research.
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备注/Memo
收稿日期:2012-10-21;改回日期:2013-03-01。
基金项目:国家自然科学基金项目（41173094，41030751）；江苏高校优势学科建设工程资助项目；江苏省教育厅重大项目（09KJA170002）
作者简介:陈瑞廷(1988-),男,山东省济宁市人,硕士研究生,主要从事土壤侵蚀与水土保持研究。E-mail:easy03026@126.com
通讯作者:张明礼(1976-),男,山东省临沂市人,博士,主要研究方向为土壤侵蚀与环境效益。E-mail:geozhml@163.com