Substantial iron sequestration during green-clay authigenesis in modern deep-sea sediments

Deep-sea sediments with high contents of rare-earth elements and yttrium (REY) are expected to serve as a potential resource for REY, which have recently been proved to be mainly contributed by phosphate component. Studies have shown that the carriers of REY in deep-sea sediments include aluminosilicate, Fe-Mn oxyhydroxides, and phosphate components. The ∑REY of the phosphate component is 1–2 orders of magnitude higher than those of the other two carriers, expressed as ∑REY = 0.001 × [Al2O3] − 0.002 × [MnO] + 0.056 × [P2O5] − 32. The sediment P2O5 content of 1.5% explains 89.1% of the total variance of the sediment ∑REY content. According to global data, P has a stronger positive correlation with ∑REY compared with Mn, Fe, Al, etc.; 45.5% of samples have a P2O5 content of less than 0.25%, and ∑REY of not higher than 400 ppm. The ∑REY of the phosphate component reaches n × 104 ppm, much higher than that of marine phosphorites and lower than that of REY-phosphate minerals, which are called REY-rich phosphates in this study. The results of microscopic observation and separation by grain size indicate that the REY-rich phosphate component is mainly composed of bioapatite. When ∑REY > 2000 ppm, the average CaO/P2O5 ratio of the samples is 1.55, indicating that the phosphate composition is between carbonate fluoroapatite and hydroxyfluorapatite. According to a knowledge map of sediment elements, the phosphate component is mainly composed of P, Ca, Sr, REY, Sc, U, and Th, and its chemical composition is relatively stable. The phosphate component has a negative Ce anomaly and positive Y anomaly, and a REY pattern similar to that of marine phosphorites and seawater. After the early diagenesis process (biogeochemistry, adsorption, desorption, transformation, and migration), the REY enrichment in the phosphate component is completed near the seawater/sediment interface. In the process of REY enrichment, the precipitation and enrichment of P is critical. According to current research progress, the REY enrichment is the result of comprehensive factors, including low sedimentation rate, high ∑REY of the bottom seawater, a non-carbonate depositional environment, oxidation conditions, and certain bottom current conditions.

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The degradation activities for three seaweed polysaccharides of Shewanella sp. WPAGA9 isolated from deep‐sea sediments

Journal of Basic Microbiology ◽

10.1002/jobm.202000728 ◽

2021 ◽

Author(s):

Dingquan Wang ◽

Jianxin Wang ◽

Runying Zeng ◽

Jie Wu ◽

Shijia V. Michael ◽

...

Keyword(s):

Deep Sea ◽

Deep Sea Sediments

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Empirical Equations of P-Wave Velocity in the Shallow and Semi-Deep Sea Sediments from the South China Sea

Journal of Ocean University of China ◽

10.1007/s11802-021-4476-y ◽

2021 ◽

Vol 20 (3) ◽

pp. 532-538

Author(s):

Guanbao Li ◽

Zhengyu Hou ◽

Jingqiang Wang ◽

Guangming Kan ◽

Baohua Liu

Keyword(s):

South China Sea ◽

Wave Velocity ◽

South China ◽

Deep Sea ◽

The South China Sea ◽

P Wave ◽

Empirical Equations ◽

China Sea ◽

P Wave Velocity ◽

Deep Sea Sediments

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Regional study of microplastics in surface waters and deep sea sediments south of the Algarve Coast

Regional Studies in Marine Science ◽

10.1016/j.rsma.2020.101488 ◽

2020 ◽

Vol 40 ◽

pp. 101488

Author(s):

Simone Lechthaler ◽

Jan Schwarzbauer ◽

Klaus Reicherter ◽

Georg Stauch ◽

Holger Schüttrumpf

Keyword(s):

Surface Waters ◽

Deep Sea ◽

Regional Study ◽

Deep Sea Sediments

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Postdepositional Changes in Deep-Sea Sediments: ABSTRACT

AAPG Bulletin ◽

10.1306/819a3eee-16c5-11d7-8645000102c1865d ◽

1972 ◽

Vol 56 ◽

Author(s):

T. A. Davies, P. R. Supko

Keyword(s):

Deep Sea ◽

Deep Sea Sediments

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Primary Production in the Water Column as Major Structuring Element of the Biogeographical Distribution and Function of Archaea in Deep-Sea Sediments of the Central Pacific Ocean

Archaea ◽

10.1155/2019/3717239 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12 ◽

Cited By ~ 3

Author(s):

Franziska Wemheuer ◽

Avril Jean Elisabeth von Hoyningen-Huene ◽

Marion Pohlner ◽

Julius Degenhardt ◽

Bert Engelen ◽

...

Keyword(s):

Pacific Ocean ◽

Primary Production ◽

Deep Sea ◽

Archaeal Community ◽

Central Pacific ◽

Central Pacific Ocean ◽

Deep Sea Sediments ◽

And Function ◽

Functional Profiles ◽

Archaeal Communities

Information on environmental conditions shaping archaeal communities thriving at the seafloor of the central Pacific Ocean is limited. The present study was conducted to investigate the diversity, composition, and function of both entire and potentially active archaeal communities within Pacific deep-sea sediments. For this purpose, sediment samples were taken along the 180° meridian of the central Pacific Ocean. Community composition and diversity were assessed by Illumina tag sequencing targeting archaeal 16S rRNA genes and transcripts. Archaeal communities were dominated by CandidatusNitrosopumilus(Thaumarchaeota) and other members of theNitrosopumilaceae(Thaumarchaeota), but higher relative abundances of the Marine Group II (Euryarchaeota) were observed in the active compared to the entire archaeal community. The composition of the entire and the active archaeal communities was strongly linked to primary production (chlorophyll content), explaining more than 40% of the variance. Furthermore, we found a strong correlation of the entire archaeal community composition to latitude and silicic acid content, while the active community was significantly correlated with primary production and ferric oxide content. We predicted functional profiles from 16S rRNA data to assess archaeal community functions. Latitude was significantly correlated with functional profiles of the entire community, whereas those of the active community were significantly correlated with nitrate and chlorophyll content. The results of the present study provide first insights into benthic archaeal communities in the Pacific Ocean and environmental conditions shaping their diversity, distribution, and function. Additionally, they might serve as a template for further studies investigating archaea colonizing deep-sea sediments.

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