Drainage morphometry of the Lishui catchment in the middle Yangtze basin, China: morphologic and tectonic implications

• Published in: Arabian journal of geosciences 2020-07, Vol.13 (13), Article 561
• Main Authors: Yang, Guifang, Chen, Zhenghong, Jiang, Jinhong
• Format: Article
• Language: English
• Subjects: Asymmetry; Catchment area; Catchments; Digital Elevation Models; Drainage; Drainage basins; Drainage patterns; Earth and Environmental Science; Earth science; Earth Sciences; Evolution; Geographic information systems; Geographical information systems; Geomorphology; Information systems; Morphology; Morphometry; Original Paper; Parameters; Plate tectonics; Pleistocene; Remote sensing; River basins; River valleys; Rivers; Soil; Soil conservation; Soil management; Soil water; Spatial variations; Tectonics; Uplift; Valleys; Water conservation; Watershed management
• ISSN: 1866-7511; 1866-7538
• DOI: 10.1007/s12517-020-05481-w

Drainage network pattern preserves an important history of river activity in response to regional tectonics and morphologic evolution. Various drainage morphometric parameters in the Lishui River basin and their correlation with tectonics have long been a challenge. In this paper, a detailed morphometric analysis including drainage asymmetry and anomalous morphological features was made by utilizing field data and a Digital Elevation Model (DEM), using Geographic Information System (GIS). The entire study basin was divided into 32 sub-basins so that the spatial variation of morphological parameters and its link to tectonics could be analyzed. Our study indicates that higher values in parameters occurred in the north Lishui River basin, which are associated with more mature drainage networks and largely differ from those of the south Lishui catchment. The basin asymmetry and relief features suggested the different stages of morphologic evolution on both sides. At least seven tectonic events have been identified in the study area. We speculate that these tectonic events initiated an important role in the formation of the geomorphic configuration of the Lishui Catchment. In addition, higher terrace sequences are selectively presented in the Loushui, Maoxi, and Youshui River valleys with structural complexity and active uplift in the late Early Pleistocene, highlighting a relatively earlier morphologic evolution. This, however, was followed by the later prompt incision of most areas in the Daoshui, Dieshui, and Suoxi River valleys, probably during the Middle Pleistocene. As a result, the hard rocks of these sub-basins were incised, producing the dissected topography. Our study further suggests that seven structural systems and later neotectonic events are the major controlling factors which frame the geomorphic pattern of the Lishui River valley. The outcome of the study may be of value to sustainable watershed level planning and management while implementing soil and water conservation measures in the region.