Landspy, a Python library and QGIS interface to landscape analysis and knickpoint evaluation

In this work we presented the landspy Python library and its QGIS user interface. This Python library allows to perform landscape analysis from Digital Elevation Models (DEMs); extraction and analysis of the drainage network, calculation of some of the most used indices and metrics in tectonic geomorphology and a real-time knickpoint analysis. In its first release allows the computation of drainage networks and channels gradients (chi metric, Hack indexes, knickpoint analysis), river profile analysis, and hypsometry. The base Python library contains classes to read and manipulate raster and grids. To compute the drainage network, the flow is modelled as a directed acyclic graph (DAG), a novel approach that has demonstrated to be more efficient that the traditional methods based on the D8 algorithm. Results can be exported as raster / vector formats or viewing directly in QGIS as temporary layers. The QGIS interface allow using the library without programming knowledge through interactive toolboxes and windows. The user can analyze different kind of channel profiles (longitudinal profile, chi-elevation, logarithmic area-slope, and ksn profile) directly through an interactive window that synchronizes with QGIS current map. This allow a real-time knickpoint evaluation and analysis without needing to use different programs, thus constituting a power tool to the spatial analysis of drainage network anomalies. We will show an example of use in the Rif Cordillera (northern Morrocco), where tectonic play an important role in the configuration and evolution of drainage networks.