民勤农田防护林对作物增产的贡献率

Assessment of the Contribution Rate of Farmland Shelterbelts on Increasing Crop Yield in Minqin

民勤绿洲农田防护林保护下的小麦产量均有胁地区和增产区的产量分布规律:胁地区为平产区产量的67.3%,增产区比平产区产量高3.3%;大片防护林庇护下的民勤绿洲,有防护林的小麦田产量比无防护林小麦田的产量高出4.7%。相对于防护林对小麦增产的贡献率,长期耕作对小麦有3.2%的增产作用。凉州区的防护林以疏通结构为主,有防护林的小麦产量高于无防护林的18.6%。比较民勤与凉州区防护林影响下的作物产量,民勤地区的防护林与其他因素共同影响对小麦增产的贡献率达到20.8%。民勤位于石羊河下游,受风沙危害严重,而小麦产量高于石羊河上游的凉州区,说明农田防护林及其它因素共同影响对民勤绿洲的粮食安全具有重要作用。

In Minqin area,under the protection of farmland shelterbelts,the wheat yield has the distribution of the impacted area and the increased area,which the yield in the impacted area is 67.3% of common yield and the yield in the increased area is 3.3% higher than common yield.The wheat yield under the protection of farmland shelterbelts is 4.7% higher than the no-shelterbelts in Minqin oasis.Compared with the contribution rate of shelterbelts on increasing wheat yield,long-term cultivation has effect on 3.2% increasing wheat yield.Farmland shelterbelts in Liangzhou district were mainly spares structure,and the wheat yield with shelterbelts protection is higher than no protection 18.6%.Compared crop yield of Minqin and crop yield of Liangzhou district under farmland shelterbelts,the contribution rate of shelter-belts and other factors on increasing wheat yield can achieve 20.8%.Minqin lies in the lower reaches of the Shiyang River,wind and sand in this area cause serious damage,however,Liangzhou lies in the upper reaches of the Shiyang River,wheat yield of Minqin is higher than wheat yield of Liangzhou,therefore,the combination of farmland shelterbelts and other factors have significant effect on food security of Minqin oasis.