中国水利

以黑龙江省东北漫川漫岗国家级水土流失重点治理区和大兴安岭东麓国家级水土流失重点治理区为研究对象，基于土壤侵蚀指标探究重点小流域治理优先序。利用自然断点法，对中度及以上土壤侵蚀强度面积占比、沟壑密度、坡度大于8°面积占比以及植被覆盖率等指标分级，采用优先级等级对比的方法，在土壤侵蚀现状和水土流失潜在发展评价的双维度上，进行重点小流域治理优先序判别。结果表明，在东北漫川漫岗治理区和大兴安岭东麓治理区，治理优先序为极迫切、迫切和较迫切的小流域数量比例均近似为3:12:5；不同治理优先序小流域面积分布存在显著差异，其面积四分位距、期望和中位数均呈较迫切>迫切>极迫切分布；无论在东北漫川漫岗治理区还是大兴安岭东麓治理区，均呈现极迫切治理小流域面积占比较小，分布侵蚀沟数量占比较大，侵蚀沟沟壑密度平均值远大于迫切和较迫切治理小流域，水土保持率平均值远小于迫切和较迫切治理小流域的特征。通过治理优先序划定，为实施差别化水土流失综合治理、提升国土空间水土保持功能提供参考。

Taking the two national key soil erosion control areas in Heilongjiang Province, namely the rolling hilly region of Northeast China and the eastern piedmont of the Greater Khingan Mountains, as study areas, this paper focused on the management priority of key small watersheds based on soil erosion indicators. Indicators including the proportion of areas with moderate and severe soil erosion, gully density, proportion of areas with slopes larger than 8°, and vegetation coverage were classifed by adopting the natural breakpoint method. From the dual dimensions of current soil erosion status and potential soil erosion risk, the priority order of key small watersheds was determined by conducting priority grade comparison. The results show that in the two studied areas, the quantitative ratio of small watersheds classifed as extremely urgent, urgent, and moderately urgent for management is approximately 3:12:5. There are signifcant differences in the area distribution of small watersheds with different management priorities. The interquartile range, expected value, and median of the watersheds all follow the order: moderately urgent > urgent > extremely urgent. In both areas, the small watersheds classifed as extremely urgent for management account for a small total area yet contain a large share of erosion gullies. Their average gully density is far higher, while the average soil and water conservation rate is considerably lower than those of small watersheds classified as urgent and moderately urgent for management. The delineation of watershed management priorities can provide theoretical reference for carrying out differentiated comprehensive soil erosion treatment and improving the soil and water conservation function of territorial space.