农田防护林带的树根会不断向耕地延伸 ,将吸取大量的水分及养分 ,使靠近林带边缘的耕地出现板结现象。为了切断林带伸向耕地的树根 ,黑龙江省友谊农场八分场在深耕犁的基础上 ,经过多次改进试验 ,改制成了1K 70型断根开沟机 (见图 1)。图 1　 1K 70型断根开沟机示意图1.悬挂拉 The roots of farmland shelterbelt will continue to extend to arable land, which will absorb a large amount of water and nutrients so that the cultivated land near the edge of the forest belt will have the phenomenon of compaction. In order to cut off the forest roots extending to the arable land, Friendship Farm, Heilongjiang Province, eight sub-field deep plow, based on the trial, after several improvements, transformed into a 1K70 type open-root trencher (see Figure 1). Fig.1 Schematic diagram of 1K 70 open-root ditching machine 1. Suspension pull