Measurement report: Impact of domestic heating on dust deposition sources in hyper-arid Qaidam Basin, northern Qinghai-Xizang Plateau

Abstract

Given the unique energy structure of the Qaidam Basin (QDB), this study systematically reveals the spatiotemporal variations in the chemical composition of atmospheric dust deposition and clarifies the key contributions of coal and biomass burning to carbonaceous aerosols, as well as their potential impacts on the Qinghai-Xizang Plateau (QXP) and global atmospheric systems. Monthly dust deposition samples were collected at six sites in the southern QDB between 2020 and 2023. Results indicated heightened carbon emissions and the higher char/soot ratio during the heating period (HP, 5.06 ± 4.08) than the non-heating period (NHP, 4.42 ± 3.09), indicating intensified seasonal solid fuel consumption. Spatially, the organic carbon (OC) and elemental carbon (EC) ratio was significantly lower in urban (3.97 ± 2.04) than that in rural areas (10.99 ± 10.00). Char-EC dominated EC (80.44 %), especially in urban areas (85.00 %), while secondary organic carbon (SOC) dominated OC (72.61 %), particularly in rural areas (87.32 %). The coal combustion (15.19 %) and biomass burning (33.55 %) as major contributors in rural areas, strongly associated with domestic heating, whereas urban dust predominantly originated from traffic (46.83 %) and industrial emissions (16.41 %). Coal consumption in QDB was greater during the HP relative to other dust sources on the QXP leads to increased atmospheric pollutant emissions, which may accelerate regional glacier melting. Consequently, integrating QDB carbonaceous aerosols into future environmental policies and climate models for the QXP is essential. This study provides a reference for investigating carbonaceous aerosols in climatically similar hyper-arid basins with intensive human activity and salt lake regions.