运用^(137)Cs示踪技术重建近30年滦河源区土壤风蚀变化过程

CONSTRUCTION OF SOIL WIND EROSION CHANGE IN THE LAST 30 YEARS IN LUANHE RIVER HEAD AREA BY ^(137)Cs TRACER

在持续调查与观测滦河源区土壤风蚀特征的基础上,对采集于滦河源区风积土剖面中土层样品的pH、有机碳质量分数、土壤颗粒组成进行了化验分析,运用ADCOM100超低本底γ谱仪测定了土壤样品137Cs的比活度,建立了研究区连续风积土壤剖面的时间序列,综合分析了不同时段风积层土壤的性状,运用土壤风蚀相对强度指数ISWE重建了滦河源区近30年来土壤风蚀变化过程.结果表明:20世纪70年代至80年代早期、80年代末期至90年代中后期均为研究区土壤风蚀较弱的时期;80年代中期、90年代末期至2002年均为土壤风蚀强化时期.并结合已有研究成果讨论了土壤风蚀变化与气候变化的相关性及其对京津地区大气环境的影响.

Based on long-term investigation and observation of wind erosion of soil, analysis of soil pH, SOC, and soil mechanical composition of horizon samples from aeolian soil profile, this paper confirms that 137^Cs activity of soil samples by low background γ-ray spectrometer ADCOM100, and establish the time series of sequential aeolian soil profile in the study area. Soil characteristics from aeolian layers of different periods were analyzed, and wind erosion of soil during the last 30 years was rebuilt by ISWE. These data indicated that the duration of weak wind erosion of soil included the periods of from 1970 s-early 1980 s, late 1980s-middle and late 1990s, intensive wind erosion of soil included the periods of the middle 1980s and late 1990s to the year 2002. Discuss the relationship between wind fluctuation of soil and climate change, and impact on atmospheric environment in Beijing and Tianjin by soil erosion was also discussed.