东北典型黑土区耕地侵蚀沟形态系统分类方法构建

Systematic morphological classification method for cultivated land erosion gullies in the typical black soil regions of Northeast

侵蚀沟形态分类是认识其发展现状和潜在危害的重要方法,探究耕地侵蚀沟形态分类特征和分布特征对把握耕地侵蚀沟防治重点,预防坡耕地水土流失具有重要意义。针对现有侵蚀沟形态分类体系指标获取难、分类结果不完整等问题,利用遥感解译数据,根据系统分类和信息科学理论,结合东北黑土区现实需求,构建了耕地侵蚀沟系统分类方法,并在典型黑土耕作区海伦市进行了验证。结果表明:1)海伦市耕地侵蚀沟具有小面积、大宽度、短长度的特点,Ⅰ类和Ⅱ类为数量最多的一级分类;Ⅱ类四等微型沟(Ⅱ4T)和Ⅱ类四等小型沟(Ⅱ4S)在二级和三级分类中数量居多,易通过高标准农田建设进行治理。2)地形要素下耕地侵蚀沟形态分布差异明显,需要特别关注在高程180~<240 m,坡长35~<55 m,坡度2°~6°,西南坡区域内的Ⅰ4T、Ⅱ4S、Ⅱ4T等发育程度较低的侵蚀沟向更高发育程度的Ⅳ4M、Ⅴ4M等类型转变,建议结合农田建设及时采取综合防治措施,以防止耕地侵蚀沟的潜在破坏。3)构建的“类+等+型”耕地侵蚀沟分类定级方法,兼顾指标的易获取性和方法的易操作性,能够精准、直观地揭示耕地侵蚀沟的形态特征及其危害情况,可为侵蚀沟和黑土耕地的协同综合治理提供方法借鉴。

Morphological classification of erosion gullies is crucial to assessing their development status and potential hazards.Investigating erosion gullies classification and distribution in cultivated land is essential for comprehensive erosion control and preventing soil and water loss on slopes.The current literature lacks definitive indicators for a comprehensive gully morphology classification system in cultivated land,resulting in incomplete classification outcomes.This study presented a comprehensive framework for organizing morphological indicators,consolidating the essential requirements for managing cultivated land gullies in Northeast China's black soil regions.It employed systematic classification and information science methodologies.Through the combination of indicators which were obtained through remote sensing interpretation,all possible types of cultivated land erosion gullies were covered as much as possible.This framework classified area indicators into five classes,widths into four grades,and lengths into five types,creating a"class+grade+type"method for erosion gullies in cultivated land.The method was empirically evaluated in black soil agricultural zones to confirm its applicability and effectiveness.The findings showed that:(1)Erosion gullies were characterized by small areas,substantial widths,and short lengths in Hailun city's cultivated lands.In the"class+grade+type"framework,class Ⅰ and Ⅱ were the most common primary categories.Notably,class Ⅱ grade 4 tiny gullies(Ⅱ4T)and class Ⅱ grade 4 small gullies(Ⅱ4S)dominated the secondary and tertiary classifications.These erosion gullies were generally poorly developed and could be effectively controlled by developing high-standard farmland.(2)The morphological distribution of erosion gullies was significantly influenced by terrain elements.Special attention was required for gullies in areas at elevations of 180-<240 m,slope lengths of 35-<55 m,slopes of 2°-6°,and on southwestern slopes.Less developed gullies in these regions,such as class I grade 4 tiny gullies(Ⅰ4T),class Ⅱ grade 4 small gullies(Ⅱ4S),and class Ⅱ grade 4 tiny gullies(Ⅱ4T),were prone to advancing to more developed stages like class Ⅳ grade 4 medium gullies(Ⅳ4M)and class V grade 4 medium gullies(Ⅴ4M).The study recommended timely and comprehensive prevention and control measures,along with farmland construction,to mitigate potential damage.(3)The“class+grade+type”method developed in this study accurately and intuitively elucidated the morphological features and hazards of cultivated land erosion gullies.This method offered practical advantages,including easy indicator acquisition and simple operation.This research validated that relying on a single morphological index was insufficient for nuanced gully identification.Instead,the robust classification system using area,length,and width indicators demonstrated high adaptability in Hailun city.This innovative method provided a valuable reference for the integrated management of gullies and cultivated land.