基于深度学习和高分遥感影像的青藏高原东部融冻泥流阶地提取研究

Extraction of solifluction terraces in the eastern Qinghai-Tibet Plateau based on deep learning and high-resolution remote sensing images

融冻泥流阶地是一种典型的斜坡冷生型冰缘地貌,在青藏高原东部发现大量古融冻泥流阶地,其空间分布对于重建该区古多年冻土分布和古气候环境具有重要意义。融冻泥流阶地纹理复杂、几何形态不一、表面覆盖多样化,导致融冻泥流阶地遥感解译和自动提取困难,然而,深度学习方法能获取上下文多尺度语义信息,提高特征表达的能力,为融冻泥流阶地的大范围提取提供了重要手段。因此,本文提出了一种基于DeepLab V3+深度学习模型和高分辨率光学遥感影像的融冻泥流阶地自动提取方法,并在四川甘孜州新都桥周边地区开展了实验研究。结果表明:与人工解译结果对比,本方法提取结果的综合精度达到0.68以上,并经野外调查验证了其有效性;在该区共识别了9203条融冻泥流阶地,主要分布在新都桥镇附近的山谷两侧;泥流阶地主要朝西北方向,坡度集中分布在20°~25°,海拔高程大部分位于3650~3750 m间,主要地表覆盖类型是草地。

Solifluction terraces is a typical slope cryogenic glacial landform.A large number of ancient paleo-so⁃lifluction terraces are found in the eastern Tibetan Plateau,and their spatial distribution is important for recon⁃structing the distribution of ancient permafrost and paleoclimatic environment in the region.The complex tex⁃ture,different geometric shapes and diverse surface coverage of solifluction terraces make remote sensing inter⁃pretation and automatic extraction of solifluction terraces very difficult.However,deep learning methods can ac⁃quire contextual multi-scale semantic information and improve feature representation,providing an important means for large-scale extraction of solifluction terraces.Therefore,this paper proposed an automatic extraction method of solifluction terraces based on the DeepLab V3+deep learning model and high-resolution optical re⁃mote sensing images,and conducted experimental research in the surrounding area of Xinduqiao,Ganzi Prefec⁃ture,Sichuan.The results show that:(1)Compared with the visual interpretation results,the comprehensive ac⁃curacy of the extraction results of this method is above 0.68,and its effectiveness were verified by field investi⁃gation;(2)A total of 9203 solifluction terraces were identified in this area,mainly distributed on both sides of the valley near Xinduqiao Town;(3)The solifluction terraces are mainly in the northwest direction,with a con⁃centrated distribution of slopes ranging from 20°to 25°,most of the elevation is from 3650 to 3750 m,and the main surface cover type is grass.