Correcting a major error in assessing organic carbon pollution in natural waters

Jiao, N.; Liu, J.; Edwards, B.; Lv, Z.; Cai, R.; Liu, Y.; Xiao, X.; Wang, J.; Jiao, F.; Wang, R.; Huang, X.; Guo, B.; Sun, J.; Zhang, R.; Zhang, Y.; Tang, K.; Zheng, Q.; Azam, F.; Batt, J.; Cai, W.-J.; He, C.; Herndl, G.J.; Hill, P.; Hutchins, D.; LaRoche, J.; Lewis, M.; MacIntyre, H.; Polimene, L.; Robinson, C.; Shi, Q.; Suttle, C.A.; Thomas, H.; Wallace, D.; Legendre, L.

Journalpaper

Correcting a major error in assessing organic carbon pollution in natural waters

Abstract

Microbial degradation of dissolved organic carbon (DOC) in aquatic environments can cause oxygen depletion, water acidification, and CO2 emissions. These problems are caused by labile DOC (LDOC) and not refractory DOC (RDOC) that resists degradation and is thus a carbon sink. For nearly a century, chemical oxygen demand (COD) has been widely used for assessment of organic pollution in aquatic systems. Here, we show through a multicountry survey and experimental studies that COD is not an appropriate proxy of microbial degradability of organic matter because it oxidizes both LDOC and RDOC, and the latter contributes up to 90% of DOC in high-latitude forested areas. Hence, COD measurements do not provide appropriate scientific information on organic pollution in natural waters and can mislead environmental policies. We propose the replacement of the COD method with an optode-based biological oxygen demand method to accurately and efficiently assess organic pollution in natural aquatic environments.

DOI Link to Publication

URL: https://publications.hereon.de/id/39807/
Authors:Jiao, N., Liu, J., Edwards, B., Lv, Z., Cai, R., Liu, Y., Xiao, X., Wang, J., Jiao, F., Wang, R., Huang, X., Guo, B., Sun, J., Zhang, R., Zhang, Y., Tang, K., Zheng, Q., Azam, F., Batt, J., Cai, W.-J., He, C., Herndl, G.J., Hill, P., Hutchins, D., LaRoche, J., Lewis, M., MacIntyre, H., Polimene, L., Robinson, C., Shi, Q., Suttle, C.A., Thomas, H., Wallace, D., Legendre, L.
Year:2021
In: Science Advances
Volume:7
Issue:16
Pages:eabc7318
Publisher:American Association for the Advancement of Science , Washington
Type:Journalpaper
ISSN: 2375-2548
Cite as: Jiao, N.; Liu, J.; Edwards, B.; Lv, Z.; Cai, R.; Liu, Y.; Xiao, X.; Wang, J.; Jiao, F.; Wang, R.; Huang, X.; Guo, B.; Sun, J.; Zhang, R.; Zhang, Y.; Tang, K.; Zheng, Q.; Azam, F.; Batt, J.; Cai, W.-J.; He, C.; Herndl, G.J.; Hill, P.; Hutchins, D.; LaRoche, J.; Lewis, M.; MacIntyre, H.; Polimene, L.; Robinson, C.; Shi, Q.; Suttle, C.A.; Thomas, H.; Wallace, D.; Legendre, L.: Correcting a major error in assessing organic carbon pollution in natural waters. In: Science Advances. Vol. 7 (2021) 16, eabc7318. (DOI: /10.1126/sciadv.abc7318)