保护性耕作对坡耕地烟田水土流失的影响

Effects of Conservation Tillage on Water Loss and Soil Erosion in Sloping Fields of Planting Flue-cured Tobacco

在重庆市石柱县坡耕地开展保护性耕作试验,探究其对水土流失的影响。于2015年在重庆市石柱县坡耕地烟田开展试验,采用顺坡起垄的方式,设置4个处理：处理T1（不种植黑麦草）、处理T2（垄间种植黑麦草）、处理T3（垄体种植黑麦草）、处理T4（垄体种植黑麦草＋垄间种植黑麦草）。结果表明：垄间种植黑麦草可有效减少小区径流量58.66%-65.79%,小区产沙量62.50%-68.78%,硝态氮流失52.05%-57.22%,铵态氮流失51.03%-59.98%,总磷流失51.47%-65.88%和钾流失66.93%-69.33%。垄体种植黑麦草可有效减少小区径流量54.32%-61.59%,小区产沙量52.95%-62.98%,硝态氮流失63.73%-77.49%,铵态氮流失59.12%-67.81%,总磷流失62.84%-76.22%,钾流失75.17%-77.84%。垄间和垄体均种植黑麦草可有效减少小区径流量92.09%-98.25%,小区产沙量86.43%-95.91%,硝态氮流失87.89%-94.99%,铵态氮流失90.19%-97.06%,总磷流失81.99%-91.94%,钾流失91.52%-93.88%。整体而言,垄间种植黑麦草＋垄体种植黑麦草处理对重庆烟区水土保持效果最佳。

The conservation tillage experiment was carried out in the sloping fields in Chongqing in order to explore the influence of conservation tillage on water loss and soil erosion,so as to provide some suggestions for soil and water conservation in Chongqing area.The field experiment was carried out in 2015 in Shizhu,Chongqing.The flue-cured tobacco variety Yunyan 87 was planted in the whole testing area,and sloping ridging was used.There were four treatments,i.e.T1,in which Lolium multiflorum Lam.was not grown,T2,in which L.multiflorum was grown between ridges,T3,in which L.multiflorum was grown on the rdiges,and T4,in which L.multiflorum was grown both between ridges and on the ridges.The results showed that growing L.multiflorumbetween ridges could effectively reduce runoff by 58.66%to 65.79%,sediment yield could be reduced by 62.50%to 68.78%,and the loss of NO3--N,NH4＋-N,phosphorus and potassium in runoff could be reduced by 52.05%to 57.22%,51.03%to 59.98%,51.47%to 65.88%,and 66.93% to 69.33%,respectively.When L.multiflorum was grown on the rdiges,the runoff,the sediment yield,the loss of NO3--N,NH4＋-N,phosphorus and potassium in runoff could be reduced by54.32%to 61.59%,52.95%to 62.98%,63.73% to 77.49%,59.12% to 67.81%,62.84% to 76.22%,and 75.17% to 77.84%,respectively.When L.multiflorum was grown both between ridges and on the rdiges,the runoff,the sediment yield,the loss of NO-3-N,NH＋4-N,phosphorus and potassium in runoff could be reduced by 92.09%to 98.25%,86.43%to 95.91%,87.89%to 94.99%,90.19%to 97.06%,81.99%to 91.94%,and 91.52%to 93.88%,respectively.Overall,growing L.multiflorumboth between ridges and on the rdiges is the best way of soil and water conservation.