Identifying and understanding alternative states of dryland landscape: A hierarchical analysis of time series of fractional vegetation-soil nexuses in China’s Hexi Corridor

•We developed a framework for state alternations of dryland landscape.•We proposed a DWT-based trends and turning points detection (DWT-TTD) algorithm.•Eight state transition pathways were reconstructed using DWT-TTD detected metrics.•We revealed synthetic degradations from interactive vegetation-soil nexus pathways.•The DWT-TTD algorithm can capture cross-scale dynamics of vegetation-soil landscape.