Spatial pattern of riparian vegetation in desert of the lower Tarim River basin

Abstract

Aims Revealing the spatial pattern of riparian vegetation in hyper-arid regions can improve our understanding on the water relations of riparian vegetation in the desert watershed ecosystem, and also can provide valuable scientific guidance for desertification control and water resources management of watershed of the arid region in northwestern China. This research objective is to show the spatial distribution and structures of typical riparian vegetation in hyper-arid desert watershed from regional and overall perspective. Methods Based on Landsat-8 OLI remote sensing images and a large number of field vegetation surveys, the supervised classification method was used to distinguish three main vegetation categories in the lower Tarim River basin: Tamarix thicket, Populus euphratica woodland, and Phragmites australis grassland. The leaf area index (LAI) of Tamarix thickets and Populus euphratica woodlands were inverted by using the remote-sensed LAI inversion empirical model that we developed. Important findings Supervised classification supporting abundant information of ground objects by remote sensing was an effective method to determine desert riparian vegetation categories in arid desert regions. The area was 336.4 km 2 for the Populus euphratica woodlands and 405.3 km 2 for the Tamarix thickets, respectively. The Tamarix thickets had a wider distribution range while the Populus euphratica woodlands grew near the river