New estimate of chemical weathering rate in Xijiang River Basin based on multi-model
Hydrochemistry and Sr isotope compositions were measured in water samples collected during high- and low-water periods from the main stream and tributaries of the Xijiang River Basin in southern China. The primary weathering end-members were analyzed and calculated using the multi-model combination...
| Published in: | Scientific Reports |
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| Main Authors: | , , , , , , , , |
| Format: | Text |
| Language: | English |
| Published: |
Nature Publishing Group UK
2021
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| Subjects: | |
| Online Access: | http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7952734/ http://www.ncbi.nlm.nih.gov/pubmed/33707460 https://doi.org/10.1038/s41598-021-84602-1 |
| Summary: | Hydrochemistry and Sr isotope compositions were measured in water samples collected during high- and low-water periods from the main stream and tributaries of the Xijiang River Basin in southern China. The primary weathering end-members were analyzed and calculated using the multi-model combination and classic hydrogeochemical method. During the high-water period, structural factors were found to be the main factors controlling chemical weathering in the basin, whereas anthropogenic activity and other random factors had a negligible influence. During the low-water period, both structural and random factors controlled chemical weathering. Through path-model and semi-variance analyses, we determined and quantified the relationship between the main weathering sources, whose results were stable; this is consistent with the inversion model. The total dissolved substances were mainly derived from carbonate weathering, which was approximately 76% (0–96%) while silicate weathering accounted for only 14% (5–19%). The inversion model results showed that the optimum silicate weathering rate was 7.264–35.551 × 10(3) mol/km(2)/year, where carbonic acid was the main factor that induces weathering. The CO(2) flux consumed by rock weathering in the basin during the study period was 150.69 × 10(9) mol/year, while the CO(2) flux consumed by carbonic acid weathering of carbonate (CCW) and silicate rocks (CSW) was 144.47 and 29.45 × 10(9) mol/year, respectively. The CO(2) flux produced by H(2)SO(4) weathered carbonate (SCW) was 23.23 × 10(9) mol/year. |
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