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作 者:刘晓光[1] 郑大玮[1] 潘学标[1] 郑秀琴 妥德宝
机构地区:[1]中国农业大学资源与环境学院,北京100094 [2]密云县气象局,北京101500 [3]内蒙古农牧科学院,呼和浩特010031
出 处:《农业工程学报》2006年第12期60-64,共5页Transactions of the Chinese Society of Agricultural Engineering
基 金:国家十五攻关课题(2001BA508B12);国家重点基础研究发展规划项目(G2000018606)
摘 要:土壤风蚀是干旱半干旱地区主要的土地退化过程,在最不适宜种植乔木防风林的半干旱农牧交错带地区,生物篱是一种有效的风障形式,它能减轻风速从而减轻风蚀。试验结果表明,在近地面(距地面5em)生物篱保护下的留茬地风速比对照裸地近地面平均降低81.25%,风蚀量减少53.96%;在篱高或茬高0~5倍范围内,随着离生物篱或留茬的距离增大,生物篱的保护作用逐渐增强,贡献率逐渐增大,更远则保护作用下降。在与不同作物残茬的组合中。生物篱与草谷子留茬组合下的抗风蚀效果更为突出,其次是油菜茬,最后是苜蓿茬,并且得出在残茬影响下,风速随高度递增的变化规律都符合指数递增规律,相关系数都达到0.84以上。Soil wind erosion is a main soil degradation process in the drough and arid-drough areas. Hedge is a form of windbreak, it can weaken wind velocity so as to reduce wind erosion. The results showed that the wind velocity was reduced by 81.25% and the quantity of wind erosion was reduced by 53.96% in crop stubble plots than ones in naked plots, and the role of hedge would be bigger if the distance was bigger from hedge at the range of 0-5 times of height of hedge. Among different integrations between hedge and different crop stubbles, the efficiency of hedge and sunflower stalk was most remarkable, then rape, last alfafa. It is concluded that wind velocity variation presented exponent trend at the different heights under the effect of hedge, and the correlation coefficient was over 0.84.
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