<正>较为系统、全面地分析了林带（网）对小麦产量的影响。得出：１林带的胁地范围大致为１５Ｈ～２０Ｈ。如采用断根措施，其胁地范围可减少０５Ｈ左右。林网中２Ｈ～１８Ｈ范围为增产区，５Ｈ～１５Ｈ内为高增产区。２林带北侧和西侧林冠遮荫胁地影响较重，东侧、南侧较轻，且离林带愈近，其影响愈大。３开挖断根沟能有效地防止林带的根系胁地影响，使距林带１Ｈ范围内小麦减产幅度显著降低。４开挖断根沟的林网内，小麦平均增产７７％，无断根林网内平均增产４７％。

The paper makes a systematic and comprehensive analysis of the effects of shelterforest belt (network) on wheat output. The conclusions are as follows: 1. The negativeinfluence scope of forestbelt is about 1.5H～2．0H　(H is the average height of forestbelt). 2. The northern and western sides of forestbelt are heavily affected by forest crown, whereas the eastern and southern sides are lightly affected. 3. It can effectively reduce effect of root system by digging rootcutting ditch. 4. The average outputincrease rate is 7．7％ in the field with rootcutting ditch, whereas only 4．7％ in the field without rootcutting ditch.