Spatial variability of nitrogen cycling in the sediments of the Danshuie River Estuary (Northern Taiwan)

Ting Chia Chang; Wei Yu Lin; Tien Hsi Fang

doi:10.1016/j.marpolbul.2023.115776

Spatial variability of nitrogen cycling in the sediments of the Danshuie River Estuary (Northern Taiwan)

Mar Pollut Bull. 2023 Dec:197:115776. doi: 10.1016/j.marpolbul.2023.115776. Epub 2023 Nov 17.

Authors

Ting Chia Chang¹, Wei Yu Lin¹, Tien Hsi Fang²

Affiliations

¹ Department of Marine Environmental Informatics, National Taiwan Ocean University, Keelung 202, Taiwan.
² Department of Marine Environmental Informatics, National Taiwan Ocean University, Keelung 202, Taiwan; Institute of Marine Biology, National Dong Hwa University, Pingtung, Taiwan. Electronic address: thfang@mail.ntou.edu.tw.

PMID: 37979530
DOI: 10.1016/j.marpolbul.2023.115776

Abstract

Dissolved N species, TOC and total N (TN) in sediment cores (SC) collected from an eutrophic estuary were analyzed to understand the N geochemical variation in SC of the eutrophic estuary. Extremely higher concentrations of ammonium (6550 μM) and DON (2050 μM) were observed in pore water of the upper estuary and both concentrations generally accounted for 65-99 % and 1-34 % of the dissolved total N pool, respectively, in the three sediment pore waters. The DON and TN concentrations decreased with increasing depth in SC of the upper estuary, opposite the ammonium profile, suggesting that the mineralization of DON and TN provided the ammonium source to the SC. While, the TN mineralization was more profound than the DON mineralization in SC of the middle and lower estuary. The mineralization rate of DON and TN obviously differed from the different depth intervals of the three SC.

Keywords: DON; Mineralization; Nitrogen species; Sediment pore water.

MeSH terms

Ammonium Compounds*
China
Environmental Monitoring
Estuaries
Geologic Sediments
Nitrogen / analysis
Rivers
Taiwan
Water Pollutants, Chemical* / analysis

Substances

Nitrogen
Water Pollutants, Chemical
Ammonium Compounds