A comparison of the early diagenetic environment in intertidal sands and muds of the Manukau Harbour, New Zealand

Williamson, R. Bruce; Hume, Terry M.; Mol‐Krijnen, John

doi:10.1007/bf00767086

Cited by 12 publications

(6 citation statements)

References 44 publications

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“…Concentrations were high in surface layers and burrow walls but low in anoxic sediment (Figs. 1–3), in line with the known behavior of Mn in sediment profiles [28, 29]. Highest concentrations were associated with bright reddish yellow burrow walls.…”

Section: Resultssupporting

confidence: 81%

“…Most of the sediments in the bioturbated layer are anoxic (i.e., they contain no measurable oxygen). There is also no sulfidic layer in these systems; the concentration of FeOOH is always sufficient to react with and to prevent the build‐up of free sulfide [28, 37], even in the dark, AVS‐rich sediments below the bioturbated layer. The AVS and FeS 2 are consistently present throughout the profile of our cores, and in fact, there is relatively little difference in FeS2 concentrations across the redox boundary between oxic and anoxic sediments (Figs.…”

Section: Discussionmentioning

confidence: 99%

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Effect of burrowing by the crab helice crassa on chemistry of intertidal muddy sedimentsa

Williamson

Wilcock

Wise

et al. 1999

Enviro Toxic and Chemistry

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The chemical environment was measured in vertical and horizontal profiles of cores taken from intertidal sediments that are extensively burrowed by the mud crab Helice crassa. The crab burrows folded the thin (2–5 mm) oxic layer into the sediment, and the burrows appeared to have a strong influence on the concentrations of acid volatile sulfide (AVS), acid‐extractable FeII (probably FeCO3 and FeS), FeIII (probably predominantly hydrous ferric oxide FeOOH), and MnII, III, IV and a modest effect on FeS2 but no effect on total organic carbon, total organic nitrogen, or acid‐extractable zinc concentrations. The oxic layer was thinner in the burrows than on the sediment surface and showed some minor differences in solid‐state chemistry, with higher FeOOH and lower FeS2 concentrations in the burrow walls. Acid volatile sulfide, FeCO3, and FeS2 were found in the oxic layers, presumably because of deposits from crab excavations of deeper anoxic sediments. The chemistry of the bioturbated profile was highly variable, not only because of existing burrows but also because of infilled abandoned burrows. The colors of the sediment profile were strongly related to the concentrations of FeII, AVS, FeIII, Mn, and FeS2. The implications of the observed sediment chemistry to the fate and bioavailability of contaminants is discussed.

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Section: Resultssupporting

confidence: 81%

Section: Discussionmentioning

confidence: 99%

Effect of burrowing by the crab helice crassa on chemistry of intertidal muddy sedimentsa

Williamson

Wilcock

Wise

et al. 1999

Enviro Toxic and Chemistry

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“…Because of the strong bioturbation, the cores had a marked 3-dimensional redox structure, as described elsewhere (Williamson et al 1994). We expected bioturbation to decrease down the core, in line with the observed density of mottling and macropores.…”

Section: Site Descriptionsupporting

confidence: 61%

“…The open burrows carry oxygenated water deep within the sediment through siphoning (Williamson et al 1994) or irrigation. This results in an extensive, albeit fragmented, 3-dimensional redox profile.…”

Section: Bioturbationmentioning

confidence: 99%

“…Several studies have shown that Pb, Zn, Cu, Cd, and Ni in sediments do not become acutely toxic to some organisms until the sum of the concentration of heavy metals exceeds the stoichiometric concentration of AVS (Ankley et al 1994). The muddy, polluted sediments in Mangere Inlet contain higher concentrations of AVS than in relatively unpolluted sandy sediments (about 100 times greater) or muds (about 10 times greater) in a relatively remote part of the Manukau Harbour (Williamson et al 1994). Hence there is a large buffer capacity for removing trace metals from solution and an enormous potential for ameliorating the acute toxicity effects of trace metals.…”

Section: +mentioning

confidence: 99%

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Trace metal partitioning in bioturbated, contaminated, surficial sediments from Mangere Inlet, New Zealand

Williamson

Mol‐Krijnen

Dam

1995

New Zealand Journal of Marine and Freshwater Research

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Diagenesis and its effects on the partitioning of trace metals was examined in intertidal muddy sediments in polluted Mangere Inlet, Manukau Harbour, New Zealand. Two cores were sectioned down to 26 cm, and analysed for compounds of Fe, Mn, S, and organic matter. Trace metals were analysed by sequential extraction (nonresidual metals), 0.5M HCl, and XRF (total metals). The sediments were bioturbated, with strong mottling of sediment colour in both cores and intact macropores in one core. Bioturbation appeared to affect sediment chemistry and to cause differences between the cores. There were changes in trace metal partitioning in the non-residual phases with depth, but the changes were relatively small, in line with the changes in major sediment phases. None of the trace metals showed an increase in the lithogenic fraction with depth and we concluded that immobilisation of trace metals by incorporation into residual phases is not an important mechanism in the surface sediments.

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Estimation of heavy metals (Cu, Zn, Pb) input into Punat Bay

Mikulić¹,

Oreščanin

Legović

et al. 2003

Environmental Geology

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A comparison of the early diagenetic environment in intertidal sands and muds of the Manukau Harbour, New Zealand

Cited by 12 publications

References 44 publications

Effect of burrowing by the crab helice crassa on chemistry of intertidal muddy sedimentsa

Effect of burrowing by the crab helice crassa on chemistry of intertidal muddy sedimentsa

Trace metal partitioning in bioturbated, contaminated, surficial sediments from Mangere Inlet, New Zealand

Estimation of heavy metals (Cu, Zn, Pb) input into Punat Bay

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