气压深松土壤孔隙度测试与分析  

Test and analysis of soil porosity with pneumatic subsoiling

作　　者：左胜甲[1] 孔德刚[1] 刘春生[2] 李紫辉[1] 张超[1] 陈爽[1] 吴艳凤[1] Zuo Shengjia Kong Degang Liu Chunsheng Li Zihui Zhang Chao Chen Shuang Wu Yanfeng(College of Engineering, Northeast Agricultural University, Harbin 150030, China School of Mechanical Engineering, Heilongjiang University of Science and Technology, Harbin 150022, China)

机构地区：[1]东北农业大学工程学院,哈尔滨150030 [2]黑龙江科技大学机械工程学院,哈尔滨150022

出　　处：《农业工程学报》2017年第1期162-166,共5页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家科技支撑计划课题(2014BAD06B04)

摘　　要：为了明晰气压深松土壤孔隙度的变化规律及其效果,利用温纳电阻率法测试气压深松前、后的土壤孔隙度,并以孔隙度增加率为指标进行分析,结果表明:深松气压和水平距离对孔隙度增加率有极显著影响(P<0.01),而犁底层容重没有显著影响;水平距离0.7 m内的土壤孔隙度增大,犁底层孔隙度增加率随水平距离增加呈现先缓慢变化在0.4 m处出现峰值后,急速减小的变化趋势,水平距离0.1~0.4 m的孔隙度增加率均值显著大于0.5~0.6 m的孔隙度增加率均值(P<0.05);深松气压2.2和1.8 MPa作用下的犁底层孔隙度增加率差异不显著,但均显著大于1.4 MPa作用下的犁底层孔隙度增加率(P<0.05),1.8 MPa为最佳深松气压。结论可为气压深松技术及其设备的研发提供依据。Pneumatic subsoiling is a novel subsoiling method based on pneumatic split technology, which injects pressure-air into cultivated soil to form fractures. In order to study the change of soil porosity during pneumatic subsoiling based on Wenner electrical sounding method, a labroatory experiment was conducted in Agricultural Machinery Laboratory of the Engineering Research Center of Northeast Agricultural University from January to April in 2016. Different soil bulk density（1.4, 1.6 and 1.8 g/cm3） and subsoiling pressure（1.4, 1.8 and 2.2 k Pa） were designed for the experiment. The initial soil moisture was kept at 18% for all the treatments. At the bottom of the soil bin, a plowpan in depth of 0.2 m was artificially designed by rolling. On the top, a plough layer was of the depth of 0.2 m. The resistivity was measured before and after subsoiling. Then the resistivity was converted into soil porosity by the model established based on a pre-experiment. Then, the porosity increase rate was used to evaluate the change of soil porosity. The results showed that the pressure had an extremely significant influence on soil porosity increase rate（P〈0.01） but the bulk density did not significantly affect the results. Thus, the change of soil porosity as affected by pressure was further investigated in soil with bulk density of 1.6 g/cm3. After subsoiling, the soil porosity increased within the horizontal distance of 0.7 m. In the plowpan（0.2-0.35 m）, the porosity increase rate increased slowly with the horizontal distance before 0.4 m and reached its peak when the horizontal distance was 0.4 m. The maximum porosity increase rate was 5.1%, 6.0% and 7.5% under the pressure of 1.4, 1.8 and 2.2 Mpa, respectively. After the peak, the porosity increase rate rapidly decreased with the increase of the horizontal distance. The average of the porosity increase rate at the horizontal distance of 0.1-0.4 m was higher than that in the 0.5-0.6 m, indicating small subsoiling effect for the horizontal distance larger than

关 键 词：孔隙度 压力 土壤 气压深松 温纳测试法 

分 类 号：S222.19[农业科学—农业机械化工程]