The Effect Of Farmland Shelterbelts On Crop Yield In Plain Regions Of China

Farmland shelterbelt is able to withstand natural disaster, improve the farmland micro-environ-ment and increase the crop yield, which made it fast development in nearly20years. With the large scale construction of farmland shelterbelts, it bringed the negative effects on crop growth near the shelterbelt edge which made it a certain impact on agricultural production, and this became the focal point between the agriculture and the forestry departments. Therefore, it had a certain practical significance in larger scale research of farmland shelterbelts acting on crop yield. The areas we selected had typical representative on farmland shelterbelts in the northeast, north China and northwest regions of China, we researched the farmland shelterbelts effecting on the crops yields with different climate types and crop species, determined the range of the negative effects on the crop in different directions, and optimized the shelterbelt structure at the same time, the research results were as follows:(1) Farmland shelterbelts in the plain regions had significantly increased on crop yields with the increasing rate of7.56%to17.65%. In northeast China, soybean yield increasing rate was14.73%, and corn yield increasing rate ranged from7.56%to17.65%. In northern China, wheat yield increasing rate was at a rate of10.50%to14.77%. Wheat yield increasing rate in the northwest region was10.65%.(2) Integrated the range of the negative effects the farmland shelterbelts acting on the crops in different directions, we learned that the negative effect on the east side ranged in0.4-0.8H, on the west side ranged in0.4-1.0H, on the south side ranged in1.0-1.4H and on the north side ranged0.5-0.7H.(3) Compared with four kinds of East-West and South-North shelterbelt structures in Chi Feng, it showed that4rows of narrow forest structure and8rows wide forest structure had less difference effecting on both sides of the crop yields in the East-West shelterbelt,7-8rows wide structure showed better yield increasing effect than the structure with4rows in the South-North shelterbelt.