垄作对旱作农田土壤风蚀影响的风洞实验研究  

Influence of Ridge Tillage on Soil Wind Erosion on Rainfed Cropland:A Wind Tunnel Simulation

作　　者：刘目兴 王静爱[1] 严平 刘连友 李小雁 

机构地区：[1]北京师范大学环境演变与自然灾害教育部重点实验室

出　　处：《水土保持学报》2005年第3期54-57,87,共5页Journal of Soil and Water Conservation

基　　金：国家"十五"科技攻关项目(2002BA517A-10)

摘　　要：通过风洞实验,在5个风速下对6种不同结构的垄作及平作对照地的土壤风蚀速率、0～20cm风沙流结构进行了模拟观测研究。结果表明:垄作下平均土壤风蚀速率较平作下降低20%～60%。垄作和平作下土壤风蚀速率均随风速的增大呈幂函数递增,但平作下递增较快。风速为15m/s是旱作农田土壤风蚀加剧的转折点,当风速大于15m/s时垄作下风蚀速率较平作下明显降低。0～20cm内,平作和垄作下输沙率与高度分别呈负指数和负线性关系。垄作下0～4cm输沙量和输沙量百分比(Q0～4/Q0～20)均低于平作。不同结构的垄作间进行比较,垄脊高度相同时,垄沟比(垄脊高度与垄顶距的比值)越大,土壤风蚀速率越小,而Q0～4/Q0～20越大;垄沟比相同时,垄脊越高,土壤风蚀速率越大,而Q0～4/Q0～20越小。Through wind tunnel experiment, the rate of wind erosion and blown sand structure under conditions of ridge tillage and flat tillage were studied. The results indicated that: The mean rates of wind erosion under ridge tillage were 20 to 40 percent less than that under flat tillage. A power function was found between the rate of wind erosion and wind velocity in the seven simulated tillage conditions, but the rate of wind erosion increased faster with the increasing wind velocity under flat tillage. Wind velocity of 15 m/s was the significant point to aggravate wind erosion, while ridge tillage greatly decreased the rate of wind erosion when the wind velocity beyond 15 m/s. In the height of 0～20 cm, the sand transport rate under flat tillage decreased with increasing height by a negative exponential function, while negative line functions were founded under ridge tillage. Under ridge tillage, the total volume of sand transport in 0～4 cm and sand transport percent between 0～4 cm and 0～20 cm (Q_(0～4)/Q_(0～20)) were less than that under flat tillage. Comparison among different kinds of ridge tillage, under the same ridge height, the rate of wind erosion decreased and Q_(0～4)/Q_(0～20) increased with increasing ratio between the height of ridge and the width of furrow. Under the same ratio between the height of ridge and the width of furrow, the rate of wind erosion increased and Q_(0～4)/Q_(0～20) decreased with the increasing height of ridge.

关 键 词：垄作 土壤风蚀 风蚀速率 风沙流结构 风洞实验 

分 类 号：S157.1[农业科学—土壤学]