Review and outlook of river morphology expression

The morphological expression of rivers provides a primary medium for human understanding of river geomorphology and the transmission of geographical information. In an ever-changing environment, constantly updated river monitoring data and products offer considerable potential for an explicit expression of river morphological characteristics and associated processes. This paper reviewed the advances in river morphology expression and examines how the various approaches can be utilized to interpret changing geomorphic features of rivers. First, taking alluvial rivers as the research object, river morphology is classified into three types of expression data and four categories of expression models. Then, the limitations of current river morphology models, such as uncertainty, inconsistency, and poor joint application, are analyzed. Finally, four outlooks are offered for improving river morphology expression, including stimulating the expression of river morphology with big data of rivers, redefining different river types, promoting multidisciplinary and interdisciplinary integration, and serving scientific management and decision-making.