中文摘要：

土壤侵蚀问题是当今世界面临主要环境问题之一，137Cs示踪作为一种应用于土壤侵蚀研究比较成熟的方法，其背景值的确定是前提。本研究通过两个疑似背景值点样品的采集，探讨了耕地土壤剖面137Cs活度的分布特征、增加样品的采集数量，并且与其他研究者的研究进行对比，确定江苏省旬容地区137Cs的背景值为1820．36Bq／m2。此活度与江苏省其他地区的背景值接近，可以用该背景值进行土壤侵蚀速率以及农业非点源污染负荷估算。

英文摘要：

Soil erosion is one of the primary environment problems in today＇s world, and 137Cs tracing technology is a mature method in studying soil erosion. It is vital to confirm the reference 137Cs inventory. The paper, giving a new method for determining the reference 137Cs inventory of soil in the region where lacks the perfect reference sample sites, studied the characteristic of 137Cs soil profile distribution and the increase of the number of the soil samples, by comparing with the other＇s studies, the determined soil reference 137Cs inventory was 1 820.36 Bq/m2 in Jurong region, Jiangsu Province. This reference inventory was close to the value nearby Jurong region in Jiangsu Province, so the activity was reliable and may be used to estimate the loss rate of soil and the load of agricultural non-point contamination.