一、更换不同类型甩刀的必要性秸秆还田是增加土壤有机质、培肥地力、解决秸秆焚烧污染环境的有效措施。近年来 ,河北、河南、山东、山西等地大力推广机械化秸秆直接粉碎还田技术 ,收到了较好的效果。据统计 ,全国秸秆切碎还田机 (以下简称还田机 )的保有量达 3万余台。目前 , First, the need to replace different types of rejection Knife straw to increase soil organic matter is to increase soil fertility, to solve the straw burning an effective measure to pollute the environment. In recent years, Hebei, Henan, Shandong, Shanxi and other places to promote mechanized straw crushing directly into the field technology, has received good results. According to statistics, the country’s straw chopping machine (hereinafter referred to as field machine) of the amount of more than 30,000 units. Currently ,