The first discovery of tiger bush in central Asia provides implications for the nature-based ecological construction in the mid-latitude extreme arid zone

Ecological restoration and construction in arid areas is the key to zero growth of global land degradation, but the nature-based ecological construction model has always been the bottleneck due to the limited water. Patched vegetation is the result of long-term adaptation of plant in water-scarce environment. As a special type of patched vegetation, the tiger bush (TB) has long been noticed in low-latitude tropical and subtropical zones, but not found in central Asia in the mid-latitude temperate zones. By integrating high resolution remote sensing image analysis, field investigation and laboratory sample analysis, this study have confirmed the existence of the TB in the temperate arid Northwest China in central Asia for the first time, explored its primary characteristics, and discussed the possible succession mechanisms. The results show that: (1) TB is mostly distributed in the broad and shallow basins and valleys between low and gentle residual mountains as well as large-scale diluvial fans; (2) TB is primarily composed of small semi-shrub species, whereof the species composition and community structure are simple; (3) the soil of TB is mainly grey brown desert soil, and the surface layer has high content of silt and clay and a weak water permeability; and (4) the typical TB will tend to become untypical TB, sparse TB, and finally real desert when the water condition goes to worse, otherwise the process will be reversed. This study expands the global distribution of TB, and provides a reference for desertification control through the nature-based ecological construction in the vast mid-latitude extreme arid zone.