中子测水法是50年代开始发展起来的用同位素中子源测量物质水分含量的方法.过去在国外已有不少这方面的研究工作[1,2].利用中子法测量土壤水分,具有不需取土样、不破坏土壤结构、可连续测量、响应迅速、灵敏度高、测量范围宽、便于实现自动控制等优点.目前在国外工农业生产和土 The neutron water test is a method of measuring the water content of matter with isotope neutron sources which has been developed since the 1950s.There have been many researches in this field in foreign countries in the past [1] and [2] With no need to take soil samples, does not destroy the soil structure, continuous measurement, rapid response, high sensitivity, wide measurement range, easy to achieve automatic control, etc. At present in foreign industrial and agricultural production and soil