中文摘要：

东北中国的黑土壤区域是在中国的最重要的生产谷物的区域之一。在这个区域的逐渐地严重的溪谷侵蚀破坏了许多农田并且减少了谷物生产。我们分析了 SPOT5 从 2007 的形象和从 2008 的 TM 形象在 Kedong 县描述溪谷和农田防风林的分布并且在溪谷侵蚀上估计农田防风林的效果。形象与显示很严肃的溪谷侵蚀的 418.51mkm ², 的平均密度揭示了 2311 溪谷。与增加斜坡坡度，在溪谷密度和防风林密度之间有一个反的趋势，显示农田防风林能阻止溪谷侵蚀。对溪谷侵蚀的农田防风林的防卫效果与距离变化了：为距离 < 120m，防卫效果一致、很强壮；为 120240m 的距离，弱线性减少在防卫效果被发现；并且为距离 > 240m，防风林的防卫效果显著地更弱。我们在 11001300mkm ² 为溪谷侵蚀的预防推荐农田防风林的最佳的种密度。

英文摘要：

The black soil region of northeast China is one of the most important grain-producing areas in China. Increasingly severe gully erosion in this region has destroyed much farmland and reduced grain production. We analyzed SPOT5 imagery from 2007 and TM imagery from 2008 to describe the distributions of gullies and farmland shelterbelts in Kedong County and to assess the effect of farmland shelterbelts on gully erosion. The ima- gery revealed 2311 gullies with average density of 418.51 m km-2, indicating very serious gully erosion. With increasing slope gradient there was an inverse trend between gully density and shelterbelt density, indicating that farmland shelterbelts can prevent gully erosion. The defense effect of farmland shelterbelts against gullyerosion varied with distance： for distances 〈120 m, the defense effect was consistent and very strong; for distances of 120-240 m, a weak linear decrease was found in the defense effect; and for distances 〉240 m, the defense effect of the shelterbelts was significantly weaker. We recommend an optimal planting density of farmland shel- terbelts for the prevention of gully erosion at 1100-1300 m km-2.