University of Tasmania
Browse

File(s) under permanent embargo

Processing of particulate organic carbon associated with secondary-treated pulp and paper mill effluent in intertidal sediments: a 13C pulse-chase experiment

journal contribution
posted on 2023-05-17, 23:08 authored by Oakes, JM, Donald RossDonald Ross, Eyre, BD
To determine the benthic transformation pathways and fate of carbon associated with secondary-treated pulp and paper mill (PPM) effluent, 13C-labeled activated sludge biomass (ASB) and phytoplankton (PHY) were added, separately, to estuarine intertidal sediments. Over 28 days, 13C was traced into sediment organic carbon, fauna, seagrass, bacteria, and microphytobenthos and into fluxes of dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) from inundated sediments, and carbon dioxide (CO2(g)) from exposed sediments. There was greater removal of PHY carbon from sediments (∼85% over 28 days) compared to ASB (∼75%). Although there was similar 13C loss from PHY and ASB plots via DIC (58% and 56%, respectively) and CO2(g) fluxes (<1%), DOC fluxes were more important for PHY (41%) than ASB (12%). Faster downward transport and loss suggest that fauna prefer PHY, due to its lability and/or toxins associated with ASB; this may account for different carbon pathways. Secondary-treated PPM effluent has lower oxygen demand than primary-treated effluent, but ASB accumulation may contribute to sediment anoxia, and respiration of ASB and PHY-derived DOC may make the water column more heterotrophic. This highlights the need to optimize secondary-treatment processes to control the quality and quantity of organic carbon associated with PPM effluent.

History

Publication title

Environmental Science and Technology

Volume

47

Issue

23

Pagination

13258-13265

ISSN

0013-936X

Department/School

Institute for Marine and Antarctic Studies

Publisher

Amer Chemical Soc

Place of publication

1155 16Th St, Nw, Washington, USA, Dc, 20036

Rights statement

Copyright 2013 American Chemical Society

Repository Status

  • Restricted

Socio-economic Objectives

Paper products and pulp

Usage metrics

    University Of Tasmania

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC