我国北方约有３３００万ｈｍ２的干旱少雨、没有灌溉条件的旱作农地，存在着旱灾频繁、粮食产量低而不稳；水土流失严重、难以持续发展的两大问题。为了探讨适合北方旱地的机械化耕作理论、技术和机具，在深入分析国内外研究成果的基础上，１９９１年开始在山西、河北建立了大规模的试验示范区，对翻耕、深松、免耕三种耕作方式，对碎秆、倒秆、立秆三种覆盖方式，开展了农机农艺结合的系统试验与配套机具的攻关研究。１９９６年又增加了耙、浅松、浅旋等表土作业，形成了更加完善的作业体系。７年系统试验结果，显示出以秸秆覆盖、少免耕加表土作业组成的保护性耕作体系，适合我国北方旱作农业条件，可以取代翻耕为主的传统耕作体系，有力地推动旱地农业的可持续发展 In northern China, there are about 33 million hm2 of dry and drought-prone agricultural lands with no irrigation conditions. There are two major problems of frequent drought, low and unstable grain output, serious soil erosion and unsustainable development. In order to explore the theory, technique and implement of mechanized farming suitable for the northern dry land, based on the deep analysis of the domestic and foreign research results, a large scale experimental demonstration area was set up in 1991 in Shanxi and Hebei. Three kinds of farming methods, broken stalks, inverted stalks, stalks three kinds of coverage, conducted a combination of agricultural machinery and agricultural systems experiments and supporting equipment research. In 1996, additional topsoil operations such as rake, shallow pine and shallow spin were added, forming a more complete operating system. Seven years of systematic test results show that the conservation tillage system composed of straw mulching and less tillage and topsoil operations is suitable for the dry farming conditions in northern China and can replace the traditional tillage system of tillage and effectively promote the development of dryland agriculture sustainable development