TY - JOUR
T1 - Characteristics of dissolved organic carbon and nitrogen in precipitation in the northern Tibetan Plateau
AU - Gao, Tanguang
AU - Kang, Shichang
AU - Chen, Rensheng
AU - Wang, Xiaoming
AU - Yang, Junhua
AU - Luo, Xi
AU - Wang, Xiaoxiang
AU - Paudyal, Rukumesh
AU - Han, Chuntan
AU - He, Ruixia
AU - Sillanpää, Mika
AU - Zhang, Yulan
N1 - Publisher Copyright:
© 2021
PY - 2021/7/1
Y1 - 2021/7/1
N2 - Dissolved organic carbon (DOC) and nitrogen (N) play essential roles in global C and N cycles. To address the possible role of DOC and N in precipitation and enrich the related global database, the characteristics of DOC and N in precipitation were investigated in a typical remote permafrost region (upper Heihe River Basin) of the northern Tibetan Plateau (TP) from February 2019 to March 2020. The results demonstrated that the average DOC and total dissolved N (TDN) concentrations in the precipitation were 1.41 ± 1.09 μg mL−1 and 0.84 ± 0.48 μg mL−1, respectively, with relatively lower concentrations in the summer. The annual DOC and TDN fluxes were estimated to be 6.42 kg ha−1 yr−1 and 3.39 kg ha−1 yr−1, respectively, indicating that precipitation was a significant factor in C and N deposition. The light-absorbing properties of precipitation DOC from the SUVA254 and spectral slope revealed that precipitation DOC containing more aromatic components and lower molecular weights mostly was present during the summer; the mass cross-section (at the wavelength of 365 nm) ranged 0.26–1.84 m2 g−1, suggesting the potential impact of DOC on climatic forcing in the area. The principal component analysis combined with air mass backward trajectories indicated that the air masses from west Siberia, Central Asia, and northwestern China most significantly influenced the precipitation C and N in the study area. The WRF-Chem simulations and aerosol vertical distributions further illustrated the air mass transport pathways, demonstrating that dust and anthropogenic emissions could be transported over the studied area by westerlies and monsoonal winds. In the study basin, the precipitation deposition of DOC and N contributed largely to the riverine DOC and N exportation during the summer and had potential ecological effects. These results highlight the importance of DOC and N deposition from precipitation in the northern TP.
AB - Dissolved organic carbon (DOC) and nitrogen (N) play essential roles in global C and N cycles. To address the possible role of DOC and N in precipitation and enrich the related global database, the characteristics of DOC and N in precipitation were investigated in a typical remote permafrost region (upper Heihe River Basin) of the northern Tibetan Plateau (TP) from February 2019 to March 2020. The results demonstrated that the average DOC and total dissolved N (TDN) concentrations in the precipitation were 1.41 ± 1.09 μg mL−1 and 0.84 ± 0.48 μg mL−1, respectively, with relatively lower concentrations in the summer. The annual DOC and TDN fluxes were estimated to be 6.42 kg ha−1 yr−1 and 3.39 kg ha−1 yr−1, respectively, indicating that precipitation was a significant factor in C and N deposition. The light-absorbing properties of precipitation DOC from the SUVA254 and spectral slope revealed that precipitation DOC containing more aromatic components and lower molecular weights mostly was present during the summer; the mass cross-section (at the wavelength of 365 nm) ranged 0.26–1.84 m2 g−1, suggesting the potential impact of DOC on climatic forcing in the area. The principal component analysis combined with air mass backward trajectories indicated that the air masses from west Siberia, Central Asia, and northwestern China most significantly influenced the precipitation C and N in the study area. The WRF-Chem simulations and aerosol vertical distributions further illustrated the air mass transport pathways, demonstrating that dust and anthropogenic emissions could be transported over the studied area by westerlies and monsoonal winds. In the study basin, the precipitation deposition of DOC and N contributed largely to the riverine DOC and N exportation during the summer and had potential ecological effects. These results highlight the importance of DOC and N deposition from precipitation in the northern TP.
KW - Dissolved organic carbon
KW - Nitrogen
KW - Permafrost
KW - Precipitation
KW - Tibetan Plateau
UR - http://www.scopus.com/inward/record.url?scp=85101588628&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2021.145911
DO - 10.1016/j.scitotenv.2021.145911
M3 - Article
C2 - 33647655
AN - SCOPUS:85101588628
SN - 0048-9697
VL - 776
JO - Science of the Total Environment
JF - Science of the Total Environment
M1 - 145911
ER -