Hydrochemical characteristics and environmental significance in different ablation period in Hulugou River Basin in Qilian Mountain

In order to research hydro-geochemistry characteristic and environmental significance of river and spring water, 68 samples were collected in different ablation periods (initial ablation period; ablation period; end ablation period) in Hulugou river basin. The results showed that the chemical type of the river and spring in different ablation period was SO42−–Ca2+–Mg2+ type in Hulugou River Basin. Compared with water samples in different ablation, the order of the total ionic concentration was the initial ablation period > the end ablation period > ablation period, with the mean was 238.29, 237.19 and 178.19 mg/L, respectively. From the analysis of ionic sources, which indicated the chemical composition of river and spring water was controlled by crustal materials during the different ablation period in the Hulugou River Basin. And the dominant processes were water–rock intersection, especially the weathering and dissolution of dolomite. Meanwhile, the results of enrichment factor also confirmed that most of the ions influenced by local soil source in study area. But the ratios of NO3−, SO42− and Cl− to Na+ also confirmed that anthropogenic also influenced the water chemistry in study area. The results are also helpful for further understanding the hydro-geochemistry characteristic in different ablation period in the alpine regions of western China and providing scientific basis for further study on hydro-geochemistry.