垄作方式对薄层黑土区坡面土壤侵蚀的影响

定量评价垄作方式对坡面土壤侵蚀的影响,可为坡面土壤侵蚀防治提供理论参考。基于2012—2015年哈尔滨市野外径流小区监测资料,探讨了顺坡垄、横坡垄、无垄作(裸地休闲对照)垄作方式对坡面土壤侵蚀的影响,分析了不同垄作方式下坡面水沙关系。结果表明:不同垄作方式下径流量和侵蚀量均具有显著差异,坡面径流量和侵蚀量均表现为无垄顺坡垄横坡垄;与无垄作试验处理相比,横坡垄作使坡面径流量和侵蚀量平均减少了92.4%和98.3%,顺坡垄作使坡面径流量和侵蚀量平均减少66.4%和72.2%。当坡度由3°增加到5°时,无垄作、顺坡垄作、横坡垄作坡面侵蚀量分别增加了0.8,8.2,5.5倍。3种垄作方式下坡面水沙关系均呈现出良好的相关关系,顺坡垄作和无垄作坡面侵蚀量随径流量的增加幅度远大于横坡垄作坡面,当坡面径流量10.0mm时,二者坡面侵蚀量急剧增加。

Effects of Ridge Tillage on Hillslope Soil Erosion in Thin Layer Black Soil Region

Quantitatively assessing the effects of ridge cultivation methods on slope soil erosion can provide important theoretical guidance for prevention slope erosion. Based on the long-term field monitoring data of runoff plot in Harbin city from 2012 to 2015, the effect of longitudinal ridge, contour ridge and flat tillage on runoff and sediment were discussed. The relationships between runoff and sediment under different ridge tillage were analyzed. The results showed that there were significant differences in runoff and sediment yield between different ridge tillage methods, showed the orders of runoff and soil loss was of flat tillage > longitudinal ridge tillage > contour ridge tillage. Compared with flat tillage, contour ridge tillage reduced the runoff and sediment yield by 92.4% and 98.3%, and longitudinal ridge tillage reduced the runoff and sediment yield by 66.4% and 72.2%. When the slope gradient increased from 3° to 5°, the soil loss increased by 0.8, 8.2, and 5.5 times, respectively under flat tillage, longitudinal ridge tillage and contour ridge tillage. The result also showed the significant correlations between runoff and sediment under three tillage methods. The increasing range of soil loss under longitudinal ridge tillage and flat tillage treatment was much larger than that under the contour ridge tillage slope. When the slope runoff was greater than 10.0 mm, soil loss under borth treatments of longitudinal ridge tillage and flat tillage increased sharply.