不同农业耕作措施下坡耕地填洼量特征与变化  

Characteristics and change of surface depression storage on sloping land with different tillage practices

作　　者：赵龙山[1,2] 侯瑞[1] 吴发启[2] 戴全厚[1] 

机构地区：[1]贵州大学林学院,贵阳550025 [2]西北农林科技大学资源环境学院,杨凌712100

出　　处：《农业工程学报》2017年第12期249-254,共6页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(41601293);贵州省科技计划项目(黔科合基础[2016]1027;黔科合[2016]支撑2835号);贵州省教育厅青年科技人才成长项目(黔教合KY字[2016]114)

摘　　要：洼地蓄水是坡耕地重要的水文要素,由于它与坡耕地产流、土壤入渗能力有关,故也是坡面水土流失研究的重要对象之一。为了进一步认识坡耕地洼地蓄水作用,该研究通过人工模拟降雨试验方法,对3种常用农业耕作措施(人工锄耕、人工掏挖、等高耕作)条件下地表填洼量特征与变化进行了深入研究,以平整坡面为对照措施。研究结果表明,实施农业耕作措施的粗糙坡面平均填洼量较平整坡面提高4~13倍,洼地蓄水量依次为等高耕作>人工掏挖>人工锄耕>平整坡面;坡度对填洼量具有重要影响,洼地蓄水量随着坡度的变化可以用幂函数关系表达(R^2>0.70)。对于粗糙坡面,当坡度从15°增大到25°过程中,洼地蓄水量逐渐趋于稳定,受坡度的影响变小;在耕作坡面上,由于降雨侵蚀造成地表微地形变化,地表糙度减小,洼地蓄水量减小,地表填洼量变化可以通过地表糙度变化进行计算。Surface depression storage, which is enhanced by various tillage practices, is an important hydrological element in the sloping land. Because surface depression storage is related to overland flow production and soil infiltration capacity, therefore, it is also one of the important factors to influence soil and water losses in the sloping land. The objective of this study was to measure the changes in surface depression storages and to analyze the characteristics of surface depression storage in the sloping land with 3 tillage practices, i.e. shallow hoeing, deep hoeing and contour ploughing. These are tillage practices commonly occurring on the Loess Plateau of China. A smooth surface served as the control measure. The tillage practices were simulated in soil box with a length of 2 m, a width of 1 m and a depth of 0.5 m. A total of 5 slope gradients were used for rainfall application in this study. Soil surface roughness of sloping land was measured and calculated using a chain method. The rainfall application was conducted using a simulator with 4 spray nozzles. The nozzles were mounted on the position of 15 m above the ground. The rainfall intensity was 90 mm/h, and the rainfall duration was 60 min. In general, surface depression storage is quantified by the maximum depressional storage, which can be calculated using various empirical equations containing roughness indices or be estimated using digital techniques. In this study, surface depression storage was measured using a field measurement method. The results showed that surface depression storages in the sloping land with tillage practices were more than 4 times that on the smooth surfaces. For the different tillage practices, the surface depression storage differed and the order of surface depression storages was contour ploughing 〉 deep hoeing 〉 shallow hoeing 〉 smooth surface. The surface depression storage decreased with the increasing cumulative rainfall. For examples, the surface depression storage decreased by 41%, 28% and 15% for contour plo

关 键 词：土壤水分 侵蚀 降水 地表糙度 模拟降雨 

分 类 号：S157.1[农业科学—土壤学]