Through point-survey for farmland shelterbelt system situation

windbreak effect

and yield performance in Jingdian's first and second irrigation areas

the functions of the shelterbelt and its ecological effects were analyzed.Results indicated that eco-protection effect was displayed remarkably in the shelterbelt's two side of the 0~6H.With the distance from the shelterbelt increasing

eco-protection efficiency weakened gradually.Eco-protection effect was improved with the increase in stand age.In the perfect area of forest network

agricultural production benefits were significant and wheat yield and maize yield were 18.3% and 13.7% more than those in control area.Thousand kernel weight in the forest network area increased by 15%～18%.However

the effect of yield-increasing by shelterbelt was reduced in unsound forest network.Results from the comprehensive analysis show that economic and ecological effects of farmland shelterbelt in the area should be further improved.