一、引言土壤的冻结不仅影响越冬作物和树木的生命活动,同时还多方面的影响着农业生产活动。我国除华中、华南及康滇三个气候区以外,其他广大地区的土壤在冬季都要冻结[1]。各地土壤的冻结情况是不会完全相同的。为了进行农业气候区划,迫切需要了解各地土壤的冻结情况。1957年,作者们曾对长春地区的土壤冻结情况进行了调查研究[2],但这还满足不了东北地区农业气候区划的需要。为此,作者们对东北地区及内蒙东部各 I. INTRODUCTION Soil freezing not only affects the life activities of overwintering crops and trees, but also influences agricultural activities in many aspects. In addition to the three climatic zones in Central China, South China and Hong Dian, the vast majority of our country’s soil is frozen in winter [1]. The freezing of soils around will not be exactly the same. In order to carry out agricultural climate zoning, there is an urgent need to understand the freezing of soil around. In 1957, the authors conducted a survey on soil freezing in Changchun [2], but this still can not meet the needs of agricultural climate division in Northeast China. To this end, the authors of the northeastern region and the eastern part of Inner Mongolia