Alhagi sparsifolia BP neural network Badain Jaran Desert Calligonum caput-medusae Ebinur Lake Basin Iso-source model N resorption North and South Mountains of Lanzhou Qinghai—Tibet Plateau RUSLE model Taklimakan Desert Taklimakan Desert Highway shelterbelt aeolian sandy soil alpine dunes bic Book Industry Communication::R Earth sciences, geography, environment, planning biomass controlling factors desert plant desertification control drip irrigation drought stress ecological protection ecological stoichiometry erosion intensity evaporation-crystallization extremely arid region geographical detector groundwater table hydrochemical characteristics ion exchange