The impact of eutrophication towards selected bacterial process rates in tropical coastal waters

Joon Hai Lim; Choon Weng Lee; Chui Wei Bong; Isao Kudo

doi:10.1016/j.marpolbul.2021.112524

The impact of eutrophication towards selected bacterial process rates in tropical coastal waters

Mar Pollut Bull. 2021 Aug:169:112524. doi: 10.1016/j.marpolbul.2021.112524. Epub 2021 May 25.

Authors

Joon Hai Lim¹, Choon Weng Lee², Chui Wei Bong³, Isao Kudo⁴

Affiliations

¹ Laboratory of Microbial Ecology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia; Institute of Ocean and Earth Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia; Institute for Advanced Studies, University of Malaya, 50603 Kuala Lumpur, Malaysia.
² Laboratory of Microbial Ecology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia; Institute of Ocean and Earth Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia. Electronic address: lee@um.edu.my.
³ Laboratory of Microbial Ecology, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia; Institute of Ocean and Earth Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia.
⁴ Graduate School of Fisheries Sciences, Hokkaido University, Sapporo, Japan.

PMID: 34049069
DOI: 10.1016/j.marpolbul.2021.112524

Abstract

The dissolved organic nutrient conditions and bacterial process rates at two tropical coastal sites in Peninsular Malaysia (Port Klang and Port Dickson) were initially studied in 2004-2005 period and later revisited in 2010-2011. We observed that dissolved organic nitrogen (DON) increased about two- and ten-fold at Port Klang and Port Dickson, respectively and resulted in a significant change in DOC:DON ratio (t ≥ 2.077, p < 0.05). Among the bacterial processes measured, bacterial respiration (BR) was lower in the 2010-2011 period at both stations (t ≥ 3.390, p < 0.01). BR also correlated to the DOC:DON ratio (R² ≥ 0.259, p < 0.01). The increase in substrate quality enabled the bacteria to respire less in the dissolved organic matter degradation. As a result, the average bacterial growth efficiency increased slightly in the 2010-2011 period.

Keywords: Bacterial production; Bacterial respiration; Dissolved organic carbon; Dissolved organic nitrogen; Eutrophication; Tropical coastal waters.

MeSH terms

Bacteria
Bacterial Physiological Phenomena*
Carbon / analysis
Eutrophication*
Malaysia
Nitrogen / analysis

Substances

Carbon
Nitrogen