甜菜轮作的必要性与缩短轮作周期的可行性李北齐，冯军，李国军（黑龙江省和平糖厂）甜菜是深根系作物，不仅吸肥量大，吸肥力强，吸肥时间长，而且蒸腾量、需水量都大，这些特点对于土壤养分、土壤结构无疑是一种破坏。轮作是人为恢复地力，合理养地、用地的一种手段。我... Beibei, Feng Jun, Li Guojun (Heilongjiang Province Peace Sugar Factory) beet is a deep root crop, not only large amount of fat absorption, strong absorption of fat, long absorption time, and the amount of transpiration, Water demand is large, these characteristics of soil nutrients, soil structure is undoubtedly a destruction. The rotation is a man-made restoration of fertility, a reasonable means of raising land and using land. I...