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通过对晋南盆地混农杨树人工林立木密度与小麦产量关系的深入研究．提出了在间种地小麦产量不低于 ３ ７５０ ｋｇ／ｈｍ２或减产幅度不大于 ２８． ０％的前提下．培育杨木中径材的最佳初植立木林行距为 ６ ｍ × ６ ｍ、第４年底进行一次间伐．可得到部分小规格中径材．６年生时立木胸径可达到中径材规格上限值．即可轮伐。
The relationship between plantation density and wheat yield in poplar plantations of mixed farming in Jinnan Basin was further studied. It is proposed that the wheat yield should be no less than 3 750 kg / hm2 or the reduction rate should not exceed 28 in the intercropping area. 0% of the premise. The best initial planting poplar wood planting grove spacing of 6 m × 6 m, at the end of the fourth interval thinning. Available in some small size medium diameter timber. 6-year-old standing diameter of wood can reach the upper limit diameter specifications. Rotation can be.