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Journal articles on the topic 'Sinking and sedimented particles'

Author: Grafiati

Published: 25 May 2024

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1

Honda, M. C., H. Kawakami, S. Watanabe, and T. Saino. "Fukushima-derived radiocesium in western North Pacific sediment traps." Biogeosciences Discussions 10, no. 2 (February 11, 2013): 2455–77. http://dx.doi.org/10.5194/bgd-10-2455-2013.

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Abstract. At two stations in the western North Pacific, K2 in the subarctic gyre and S1 in the subtropical gyre, time-series sediment traps were collecting sinking particles when the Fukushima Daiichi Nuclear Power Plant (FNPP1) accident occurred on 11 March 2011. Radiocesium (134Cs and 137Cs) derived from FNPP1 accident was detected in sinking particles collected at 500 m by late March 2011 and at 4810 m by early April 2011 at both stations. The sinking velocity of 134Cs and 137Cs was estimated to be 8 to 36 m day−1 between the surface and 500 m and > 180 m day−1 between 500 m and 4810 m. 137Cs specific activity varied from 0.14 to 0.25 Bq g−1 dry weight. These values are higher than those of surface seawater, suspended particles, and zooplankton collected in April 2011. Although the radiocesium may have been adsorbed onto or incorporated into clay minerals, correlations between 134Cs and lithogenic material were not always significant; therefore, the form of the cesium associated with the sinking particles is still an open question. The total 137Cs flux by late June at K2 and by late July at S1 was 0.5 to 1.7 Bq m−2 at both depths. Compared with 137Cs input to both stations by April 2011, estimated from the surface 137Cs activity and mixed layer depth and by assuming that the observed 137Cs flux was constant throughout the year, the estimated removal rate of 137Cs from the upper layer (residence time in the upper layer) was 0.3 to 1.5% (68 to 312 yr). The estimated removal rates and residence times are comparable to previously reported values.

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2

Coppola, Alysha I., Lori A. Ziolkowski, Caroline A. Masiello, and Ellen R. M. Druffel. "Aged black carbon in marine sediments and sinking particles." Geophysical Research Letters 41, no. 7 (April 1, 2014): 2427–33. http://dx.doi.org/10.1002/2013gl059068.

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3

Rontani, J. F., B. Charriere, A. Forest, S. Heussner, F. Vaultier, M. Petit, N. Delsaut, L. Fortier, and R. Sempéré. "Intense photooxidative degradation of planktonic and bacterial lipids in sinking particles collected with sediment traps across the Canadian Beaufort Shelf (Arctic Ocean)." Biogeosciences Discussions 9, no. 6 (June 26, 2012): 7743–81. http://dx.doi.org/10.5194/bgd-9-7743-2012.

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Abstract. The lipid content of seven samples of sinking particles collected with sediment traps moored at ~100 m depth in summer and fall across the Canadian Beaufort Shelf (Arctic Ocean) was investigated. Our main goal was to quantify and characterize the biotic and abiotic degradation processes that acted on sinking material during these periods. Diatoms, which dominated the phytoplanktonic assemblage in every trap sample, appeared to be remarkably sensitive to Type II (i.e. involving singlet oxygen) photodegradation processes in summer, but seemed to be relatively unaffected by biotic degradation at the same time. Hence, the relative recalcitrance of phytodetritus towards biodegradation processes during the Arctic midnight sun period was attributed to the strong photodegradation state of heterotrophic bacteria, which likely resulted from the efficient transfer of singlet oxygen from photodegraded phytoplanktonic cells to attached bacteria. In addition, the detection in trap samples of photoproducts specific to wax ester components found in herbivorous copepods demonstrated that zooplanktonic faecal material exported out of the euphotic zone in summer were as well affected by Type II photodegradation processes. By contrast, sinking particles collected during the autumn were not influenced by any light-driven stress. Further chemical analyses showed that photodegraded sinking particles contained an important amount of intact hydroperoxides, which could then induce a strong oxidative stress in underlying sediments.

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Rontani, J. F., B. Charriere, A. Forest, S. Heussner, F. Vaultier, M. Petit, N. Delsaut, L. Fortier, and R. Sempéré. "Intense photooxidative degradation of planktonic and bacterial lipids in sinking particles collected with sediment traps across the Canadian Beaufort Shelf (Arctic Ocean)." Biogeosciences 9, no. 11 (November 23, 2012): 4787–802. http://dx.doi.org/10.5194/bg-9-4787-2012.

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Abstract. The lipid content of seven samples of sinking particles collected with sediment traps moored at ~ 100 m depth in summer and fall across the Canadian Beaufort Shelf (Arctic Ocean) was investigated. Our main goal was to quantify and characterize the biotic and abiotic degradation processes that acted on sinking material during these periods. Diatoms, which dominated the phytoplanktonic assemblage in every trap sample, appeared to be remarkably sensitive to Type II (i.e. involving singlet oxygen) photodegradation processes in summer, but seemed to be relatively unaffected by biotic degradation at the same time. Hence, the relative recalcitrance of phytodetritus towards biodegradation processes during the Arctic midnight sun period was attributed to the strong photodegradation state of heterotrophic bacteria, which likely resulted from the efficient transfer of singlet oxygen from photodegraded phytoplanktonic cells to attached bacteria. In addition, the detection in trap samples of photoproducts specific to wax ester components found in herbivorous copepods demonstrated that zooplanktonic faecal material exported out of the euphotic zone in summer were affected by Type II photodegradation processes as well. By contrast, sinking particles collected during the autumn were not influenced by any light-driven stress. Further chemical analyses showed that photodegraded sinking particles contained an important amount of intact hydroperoxides, which could then induce a strong oxidative stress in underlying sediments.

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5

Boxhammer, T., L. T. Bach, J. Czerny, and U. Riebesell. "Technical Note: Sampling and processing of mesocosm sediment trap material for quantitative biogeochemical analysis." Biogeosciences Discussions 12, no. 22 (November 23, 2015): 18693–722. http://dx.doi.org/10.5194/bgd-12-18693-2015.

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Abstract. Sediment traps are the most common tool to investigate vertical particle flux in the marine realm. However, the spatial decoupling between particle formation and collection often handicaps reconciliation of these two processes even within the euphotic zone. Pelagic mesocosms have the advantage of being closed systems and are therefore ideally suited to study how processes in natural plankton communities influence particle formation and settling in the ocean's surface. We therefore developed a protocol for efficient sample recovery and processing of quantitatively collected pelagic mesocosm sediment trap samples. Sedimented material was recovered by pumping it under gentle vacuum through a silicon tube to the sea surface. The particulate matter of these samples was subsequently concentrated by passive settling, centrifugation or flocculation with ferric chloride and we discuss the advantages of each approach. After concentration, samples were freeze-dried and ground with an easy to adapt procedure using standard lab equipment. Grain size of the finely ground samples ranges from fine to coarse silt (2–63 μm), which guarantees homogeneity for representative subsampling, a widespread problem in sediment trap research. Subsamples of the ground material were perfectly suitable for a variety of biogeochemical measurements and even at very low particle fluxes we were able to get a detailed insight on various parameters characterizing the sinking particles. The methods and recommendations described here are a key improvement for sediment trap applications in mesocosms, as they facilitate processing of large amounts of samples and allow for high-quality biogeochemical flux data.

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Boxhammer, Tim, Lennart T. Bach, Jan Czerny, and Ulf Riebesell. "Technical note: Sampling and processing of mesocosm sediment trap material for quantitative biogeochemical analysis." Biogeosciences 13, no. 9 (May 13, 2016): 2849–58. http://dx.doi.org/10.5194/bg-13-2849-2016.

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Abstract. Sediment traps are the most common tool to investigate vertical particle flux in the marine realm. However, the spatial and temporal decoupling between particle formation in the surface ocean and particle collection in sediment traps at depth often handicaps reconciliation of production and sedimentation even within the euphotic zone. Pelagic mesocosms are restricted to the surface ocean, but have the advantage of being closed systems and are therefore ideally suited to studying how processes in natural plankton communities influence particle formation and settling in the ocean's surface. We therefore developed a protocol for efficient sample recovery and processing of quantitatively collected pelagic mesocosm sediment trap samples for biogeochemical analysis. Sedimented material was recovered by pumping it under gentle vacuum through a silicon tube to the sea surface. The particulate matter of these samples was subsequently separated from bulk seawater by passive settling, centrifugation or flocculation with ferric chloride, and we discuss the advantages and efficiencies of each approach. After concentration, samples were freeze-dried and ground with an easy to adapt procedure using standard lab equipment. Grain size of the finely ground samples ranged from fine to coarse silt (2–63 µm), which guarantees homogeneity for representative subsampling, a widespread problem in sediment trap research. Subsamples of the ground material were perfectly suitable for a variety of biogeochemical measurements, and even at very low particle fluxes we were able to get a detailed insight into various parameters characterizing the sinking particles. The methods and recommendations described here are a key improvement for sediment trap applications in mesocosms, as they facilitate the processing of large amounts of samples and allow for high-quality biogeochemical flux data.

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7

Berezina, Anfisa, Evgeniy Yakushev, Oleg Savchuk, Christian Vogelsang, and André Staalstrom. "Modelling the Influence from Biota and Organic Matter on the Transport Dynamics of Microplastics in the Water Column and Bottom Sediments in the Oslo Fjord." Water 13, no. 19 (September 28, 2021): 2690. http://dx.doi.org/10.3390/w13192690.

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The fate of microplastics (MP) in seawater is heavily influenced by the biota: the density of MP particles can be changed due to biofouling, which affects sinking, or MP can be digested by zooplankton and transferred into fecal pellets with increased sinking rate. We hypothesize that seasonal production and degradation of organic matter, and corresponding changes in the plankton ecosystem affect the MP capacity for transportation and burying in sediments in different seasons. This is simulated with a coupled hydrodynamical-biogeochemical model that provides a baseline scenario of the seasonal changes in the planktonic ecosystem and changes in the availability of particulate and dissolved organic matter. In this work, we use a biogeochemical model OxyDep that simulates seasonal changes of phytoplankton (PHY), zooplankton (HET), dissolved organic matter (DOM) and detritus (POM). A specifically designed MP module considers MP particles as free particles (MPfree), particles with biofouling (MPbiof), particles consumed by zooplankton (MPhet) and particles in detritus, including fecal pellets (MPdet). A 2D coupled benthic-pelagic vertical transport model 2DBP was applied to study the effect of seasonality on lateral transport of MP and its burying in the sediments. OxyDep and MP modules were coupled with 2DBP using Framework for Aquatic Biogeochemical Modelling (FABM). A depletion of MP from the surface water and acceleration of MP burying in summer period compared to the winter was simulated numerically. The calculations confirm the observations that the “biological pump” can be one of the important drivers controlling the quantity and the distribution of MP in the water column.

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8

Gaye-Haake, B., N. Lahajnar, K. Ch Emeis, D. Unger, T. Rixen, A. Suthhof, V. Ramaswamy, et al. "Stable nitrogen isotopic ratios of sinking particles and sediments from the northern Indian Ocean." Marine Chemistry 96, no. 3-4 (September 2005): 243–55. http://dx.doi.org/10.1016/j.marchem.2005.02.001.

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9

Mirnaghi, Fatemeh, Yujuan Hua, Bruce P. Hollebone, and Carl E. Brown. "Evaluation of Oil-Sediment Interactions and the Possibility of Oil Sinking in Marine Environments." International Oil Spill Conference Proceedings 2017, no. 1 (May 1, 2017): 2017–217. http://dx.doi.org/10.7901/2169-3358-2017.1.2017-217.

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ABSTRACT 2017-217 One of the major unknowns with respect to the fate and behavior of spilled dilbit is its state of buoyancy, particularly when mixed with sediments. What form do diluted bitumen and sediment mixtures take, and will they float or sink in water column? In this study, we evaluated the fate and behavior of Cold Lake Blend-Winter at three different weathering states (i.e., fresh, medium, and heavily weathered) in high-energy mixing marine conditions, with (and without) sufficient concentrations of sediments to ensure formation of oil-particulate aggregates (OPA). Conventional light crude oil and intermediate and heavy fuel oils were also included to serve as references for behavior of other types of oils. Two mineral sediments including kaolin (fine) and sand (coarse) as well as natural sediment from the Douglas Channel (DC) in northern British Columbia, (medium) were used for this evaluation. The resulting OPAs were characterized in terms of buoyancy, OPA density, particle size distribution, and morphology to better understand the oil-sediment interaction. In the absence of sediment, mixing of the oils with water resulted in meso/entrained–water-in-oil mixtures; these mixtures remained floating on the water surface. However, in presence of kaolin or the DC sediments, a significant portion of the OPA sank to the bottom of the water column for all oils, with the exception of the light crude oil and the highly weathered Cold Lake Blend-Winter. The later did not uptake as much sediment and instead formed discrete free-floating tarballs. In experiments with the larger sand sediment, no OPAs formed. The density and particle size analysis revealed that the OPAs of the oils with higher viscosity tended to have larger densities and particle sizes. Microscopic examination of the OPAs showed that all consisted of oil droplets surrounded by sediment particles and were present in single droplet or multiple-droplet clusters.

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10

Ostrovsky, I., and Y. Z. Yacobi. "Organic matter and pigments in surface sediments: possible mechanisms of their horizontal distributions in a stratified lake." Canadian Journal of Fisheries and Aquatic Sciences 56, no. 6 (June 1, 1999): 1001–10. http://dx.doi.org/10.1139/f99-032.

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The analysis of spatial changes of organic matter and pigments (chlorophyll a, chlorophyll b, bacteriochlorophyll e, and phaeophytin a) in the uppermost bottom sediments was used to distinguish between sources of settled material in Lake Kinneret (Israel) during thermal stratification. The proportion of phytobenthic chlorophyll a decreased relatively to total chlorophyll a down to zero at 17 m. Bacteriochlorophyll e, derived from Chlorobium phaeobacteroides, was the most abundant pigment below the thermocline. Organic matter content in the sand-free sediment fraction and chlorophyll a to organic matter ratio were the lowest in the bottom area most extensively affected by shoaling internal seiches and where resuspension occurred. The proportion of resuspended matter sharply decreased with bottom depth in the hypolimnion. The importance of degraded materials of planktonic origin apparently increased towards the lake center. These distribution patterns could be achieved by dispersion of the rapidly sinking resuspended particles with fast metalimnetic jets and by focusing of the lighter planktonic particles by water motions in the turbulent benthic boundary layer. Our study showed that analysis of distribution of freshly settled organic components on the bottom may be a useful tool for understanding particle transport mechanisms in lakes.

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11

Yoshikawa, Takashi, Kenichi Kanemata, Gentoku Nakase, and Mitsuru Eguchi. "Microbial decomposition process of organic matter in sinking particles, resuspendable particles, and bottom sediments at a coastal fish farming area." Fisheries Science 83, no. 4 (June 8, 2017): 635–47. http://dx.doi.org/10.1007/s12562-017-1098-9.

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12

Waniek, Joanna, Wolfgang Koeve, and Ralf D. Prien. "Trajectories of sinking particles and the catchment areas above sediment traps in the northeast Atlantic." Journal of Marine Research 58, no. 6 (November 1, 2000): 983–1006. http://dx.doi.org/10.1357/002224000763485773.

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13

Laurenceau-Cornec, E. C., T. W. Trull, D. M. Davies, S. G. Bray, J. Doran, F. Planchon, F. Carlotti, et al. "The relative importance of phytoplankton aggregates and zooplankton fecal pellets to carbon export: insights from free-drifting sediment trap deployments in naturally iron-fertilised waters near the Kerguelen Plateau." Biogeosciences 12, no. 4 (February 17, 2015): 1007–27. http://dx.doi.org/10.5194/bg-12-1007-2015.

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Abstract. The first KErguelen Ocean and Plateau compared Study (KEOPS1), conducted in the naturally iron-fertilised Kerguelen bloom, demonstrated that fecal material was the main pathway for exporting carbon to the deep ocean during summer (January–February 2005), suggesting a limited role of direct export via phytodetrital aggregates. The KEOPS2 project reinvestigated this issue during the spring bloom initiation (October–November 2011), when zooplankton communities may exert limited grazing pressure, and further explored the link between carbon flux, export efficiency and dominant sinking particles depending upon surface plankton community structure. Sinking particles were collected in polyacrylamide gel-filled and standard free-drifting sediment traps (PPS3/3), deployed at six stations between 100 and 400 m, to examine flux composition, particle origin and their size distributions. Results revealed an important contribution of phytodetrital aggregates (49 ± 10 and 45 ± 22% of the total number and volume of particles respectively, all stations and depths averaged). This high contribution dropped when converted to carbon content (30 ± 16% of total carbon, all stations and depths averaged), with cylindrical fecal pellets then representing the dominant fraction (56 ± 19%). At 100 and 200 m depth, iron- and biomass-enriched sites exhibited the highest carbon fluxes (maxima of 180 and 84 ± 27 mg C m-2 d-1, based on gel and PPS3/3 trap collection respectively), especially where large fecal pellets dominated over phytodetrital aggregates. Below these depths, carbon fluxes decreased (48 ± 21% decrease on average between 200 and 400 m), and mixed aggregates composed of phytodetritus and fecal matter dominated, suggesting an important role played by physical aggregation in deep carbon export. Export efficiencies determined from gels, PPS3/3 traps and 234Th disequilibria (200 m carbon flux/net primary productivity) were negatively correlated to net primary productivity with observed decreases from ~ 0.2 at low-iron sites to ~ 0.02 at high-iron sites. Varying phytoplankton communities and grazing pressure appear to explain this negative relationship. Our work emphasises the need to consider detailed plankton communities to accurately identify the controls on carbon export efficiency, which appear to include small spatio-temporal variations in ecosystem structure.

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Laurenceau, E. C., T. W. Trull, D. M. Davies, S. G. Bray, J. Doran, F. Planchon, F. Carlotti, et al. "The relative importance of phytoplankton aggregates and zooplankton fecal pellets to carbon export: insights from free-drifting sediment trap deployments in naturally iron-fertilised waters near the Kerguelen plateau." Biogeosciences Discussions 11, no. 9 (September 19, 2014): 13623–73. http://dx.doi.org/10.5194/bgd-11-13623-2014.

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Abstract. The first KErguelen Ocean and Plateau compared Study (KEOPS1), conducted in the naturally iron-fertilised Kerguelen bloom, demonstrated that fecal material was the main pathway for exporting carbon to the deep ocean during summer (January–February~2005), suggesting a~limited role of direct export via phytodetrital aggregates. The KEOPS2 project re-investigated this issue during the spring bloom initiation (October–November 2011), when zooplankton communities may exert limited grazing pressure, and explored further the link between carbon flux, export efficiency and dominant sinking particles depending upon surface plankton community structure. Sinking particles were collected in polyacrylamide gel-filled and standard free-drifting sediment traps (PPS3/3), deployed at six stations between 100 and 400 m to examine flux composition, particle origin and their size distributions. Results revealed an important contribution of phytodetrital aggregates (49 ± 10% and 45 ± 22% of the total number and volume of particles respectively, all stations and depths averaged). This high contribution dropped when converted to carbon content (30 ± 16% of total carbon, all stations and depths averaged), cylindrical fecal pellets representing then the dominant fraction (56 ± 19%). At 100 and 200 m depth, iron and biomass enriched sites exhibited the highest carbon fluxes (maxima of 180 and 84 ± 27 mg C m−2 d−1; based on gel and PPS3/3 trap collection respectively), especially where large fecal pellets dominated over phytodetrital aggregates. Below these depths, carbon fluxes decreased (48 ± 21% decrease in average between 200 and 400 m), and mixed aggregates composed of phytodetritus and fecal matter dominated, suggesting an important role played by physical aggregation in deep carbon export. Export efficiencies determined from gels, PPS3/3 traps and 234Th disequilibria (200 m carbon flux/net primary productivity), were negatively correlated to net primary productivity with observed decreases from ~ 0.2 at low-iron sites to ~ 0.02 at high-iron sites. Varying phytoplankton communities and grazing pressure appear to explain this negative relationship. Our work emphasizes the need to consider detailed plankton community structure to accurately identify the controls on carbon export efficiency, which appear to include small spatio-temporal variations of ecosystem structure.

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Zúñiga, Diana, Celia Santos, María Froján, Emilia Salgueiro, Marta M. Rufino, Francisco De la Granda, Francisco G. Figueiras, Carmen G. Castro, and Fátima Abrantes. "Diatoms as a paleoproductivity proxy in the NW Iberian coastal upwelling system (NE Atlantic)." Biogeosciences 14, no. 5 (March 13, 2017): 1165–79. http://dx.doi.org/10.5194/bg-14-1165-2017.

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Abstract. The objective of the current work is to improve our understanding of how water column diatom's abundance and assemblage composition is seasonally transferred from the photic zone to seafloor sediments. To address this, we used a dataset derived from water column, sediment trap and surface sediment samples recovered in the NW Iberian coastal upwelling system. Diatom fluxes (2.2 (±5.6) 106 valves m−2 d−1) represented the majority of the siliceous microorganisms sinking out from the photic zone during all studied years and showed seasonal variability. Contrasting results between water column and sediment trap diatom abundances were found during downwelling periods, as shown by the unexpectedly high diatom export signals when diatom-derived primary production achieved their minimum levels. They were principally related to surface sediment remobilization and intense Minho and Douro river discharge that constitute an additional source of particulate matter to the inner continental shelf. In fact, contributions of allochthonous particles to the sinking material were confirmed by the significant increase of both benthic and freshwater diatoms in the sediment trap assemblage. In contrast, we found that most of the living diatom species blooming during highly productive upwelling periods were dissolved during sinking, and only those resistant to dissolution and the Chaetoceros and Leptocylindrus spp. resting spores were susceptible to being exported and buried. Furthermore, Chaetoceros spp. dominate during spring–early summer, when persistent northerly winds lead to the upwelling of nutrient-rich waters on the shelf, while Leptocylindrus spp. appear associated with late-summer upwelling relaxation, characterized by water column stratification and nutrient depletion. These findings evidence that the contributions of these diatom genera to the sediment's total marine diatom assemblage should allow for the reconstruction of different past upwelling regimes.

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Kim, Hyung Jeek, Dongseon Kim, Kiseong Hyeong, Jeomshik Hwang, Chan Min Yoo, Dong Jin Ham, and Inah Seo. "Evaluation of Resuspended Sediments to Sinking Particles by Benthic Disturbance in the Clarion-Clipperton Nodule Fields." Marine Georesources & Geotechnology 33, no. 2 (October 24, 2014): 160–66. http://dx.doi.org/10.1080/1064119x.2013.815675.

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Funaki, Hironori, Kazuya Yoshimura, Kazuyuki Sakuma, Shatei Iri, and Yoshihiro Oda. "Evaluation of particulate 137Cs discharge from a mountainous forested catchment using reservoir sediments and sinking particles." Journal of Environmental Radioactivity 189 (September 2018): 48–56. http://dx.doi.org/10.1016/j.jenvrad.2018.03.004.

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Funaki, Hironori, Kazuya Yoshimura, Kazuyuki Sakuma, Shatei Iri, and Yoshihiro Oda. "Evaluation of particulate 137Cs discharge from a mountainous forested catchment using reservoir sediments and sinking particles." Journal of Environmental Radioactivity 210 (December 2019): 105814. http://dx.doi.org/10.1016/j.jenvrad.2018.09.012.

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Bouloubassi, Ioanna, Laurence Méjanelle, Romain Pete, Joëlle Fillaux, Anne Lorre, and Vanessa Point. "PAH transport by sinking particles in the open Mediterranean Sea: A 1 year sediment trap study." Marine Pollution Bulletin 52, no. 5 (May 2006): 560–71. http://dx.doi.org/10.1016/j.marpolbul.2005.10.003.

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Yoshikawa, Takashi, Kenichi Kanemata, Gentoku Nakase, and Mitsuru Eguchi. "Erratum to: Microbial decomposition process of organic matter in sinking particles, resuspendable particles, and bottom sediments at a coastal fish farming area." Fisheries Science 83, no. 6 (September 15, 2017): 1077. http://dx.doi.org/10.1007/s12562-017-1132-y.

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Ergül, H. A., S. Topcuoğlu, E. Ölmez, and Ç. Kırbaşoğlu. "Heavy metals in sinking particles and bottom sediments from the eastern Turkish coast of the Black Sea." Estuarine, Coastal and Shelf Science 78, no. 2 (June 2008): 396–402. http://dx.doi.org/10.1016/j.ecss.2008.01.006.

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Siegel, D. A., and W. G. Deuser. "Trajectories of sinking particles in the Sargasso Sea: modeling of statistical funnels above deep-ocean sediment traps." Deep Sea Research Part I: Oceanographic Research Papers 44, no. 9-10 (September 1997): 1519–41. http://dx.doi.org/10.1016/s0967-0637(97)00028-9.

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23

Kahru, Mati, Ralf Goericke, Thomas B. Kelly, and Michael R. Stukel. "Satellite estimation of carbon export by sinking particles in the California Current calibrated with sediment trap data." Deep Sea Research Part II: Topical Studies in Oceanography 173 (March 2020): 104639. http://dx.doi.org/10.1016/j.dsr2.2019.104639.

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Yoshikawa, Takashi, Kennichi Kanemata, Gentoku Nakase, and Mitsuru Eguchi. "Microbial mineralization of organic matter in sinking particles, bottom sediments and seawater in a coastal fish culturing area." Aquaculture Research 43, no. 12 (October 10, 2011): 1741–55. http://dx.doi.org/10.1111/j.1365-2109.2011.02978.x.

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Liu, Jin, Jinming Song, Huamao Yuan, Xuegang Li, Ning Li, and Liqin Duan. "Rare earth element and yttrium geochemistry in sinking particles and sediments of the Jiaozhou Bay, North China: Potential proxy assessment for sediment resuspension." Marine Pollution Bulletin 144 (July 2019): 79–91. http://dx.doi.org/10.1016/j.marpolbul.2019.04.044.

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Liu, Jin, Jinming Song, Huamao Yuan, Xuegang Li, Ning Li, and Liqin Duan. "Trace metal comparative analysis of sinking particles and sediments from a coastal environment of the Jiaozhou Bay, North China: Influence from sediment resuspension." Chemosphere 232 (October 2019): 315–26. http://dx.doi.org/10.1016/j.chemosphere.2019.05.090.

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Antia, A. N. "Solubilization of particles in sediment traps: revising the stoichiometry of mixed layer export." Biogeosciences 2, no. 2 (August 4, 2005): 189–204. http://dx.doi.org/10.5194/bg-2-189-2005.

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Abstract. Sinking particles, once caught in sediment trap jars, release dissolved elements into the surrounding medium through leaching from their pore fluids, chemical dissolution and the activity of free exoenzymes. This results in an increase in dissolved elements in the trap jar supernatant. Elemental fluxes as traditionally measured by sediment traps underestimate total export when this particle-associated dissolved flux is not considered. The errors introduced are variable and alter both the absolute levels of flux as well as the stoichiometry of export. These errors have been quantified and corrections applied for samples from sediment traps in the North Atlantic based on measurements of excess dissolved carbon, nitrogen, phosphorus, silica and calcium in the supernatant of the collection cups. At the base of the winter mixed layer, on average 90±6% of phosphorus fluxes are found as excess phosphate whereas for carbon and nitrogen dissolved concentrations account for 30 (±8)% and 47(±11)% of total fluxes respectively. Excess dissolved silica is on average 61 (±17)% of total biogenic silica flux. Little (<10%) of calcium is solubilized. The proportion of dissolved to total flux decreases with trap deployment depth. Calculations of the C:N:P ratios for particles only are well above the Redfield ratios of 106:16:1 (Redfield et al., 1963), although the mid-water dissolved N:P and N:Si values as well as the C:N:P ratios of remineralisation along isopycnals conform to the Redfield ratios at this site. Accounting for dissolved fluxes of all these elements brings the stoichiometry of export in agreement with the Redfield Ratio and with other geochemical estimates of winter mixed layer export. A factor of 3 to 4 higher ratios of organic: inorganic carbon export also implies that the net atmospheric CO2 sequestration by the biological pump is about 50% higher at this site when the dissolved elemental fluxes are considered. Solubilization is thus a process that should be accounted for in protocols used to measure vertical fluxes with sediment traps.

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Hwang, Jeomshik, Ellen R. M. Druffel, and Timothy I. Eglinton. "Widespread influence of resuspended sediments on oceanic particulate organic carbon: Insights from radiocarbon and aluminum contents in sinking particles." Global Biogeochemical Cycles 24, no. 4 (November 20, 2010): n/a. http://dx.doi.org/10.1029/2010gb003802.

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Winton, V. H. L., G. B. Dunbar, C. B. Atkins, N. A. N. Bertler, B. Delmonte, P. S. Andersson, A. Bowie, and R. Edwards. "The origin of lithogenic sediment in the south-western Ross Sea and implications for iron fertilization." Antarctic Science 28, no. 4 (February 26, 2016): 250–60. http://dx.doi.org/10.1017/s095410201600002x.

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AbstractSummer iron (Fe) fertilization in the Ross Sea has previously been observed in association with diatom productivity, lithogenic particles and excess Fe in the water column. This productivity event occurred during an early breakout of sea ice via katabatic winds, suggesting that aeolian dust could be an important source of lithogenic Fe required for diatom growth in the Ross Sea. Here we investigate the provenance of size-selected dust deposited on sea ice in McMurdo Sound, south-western (SW) Ross Sea. The isotopic signature of McMurdo Sound dust (0.70533<87Sr/86Sr<0.70915 and -1.1<εNd(0)<3.45) confirms that dust is locally sourced from the McMurdo Sound debris bands and comprises a two-component mixture of McMurdo Volcanic Group and southern Victoria Land lithologies. In addition, the provenance of lithogenic sediment trapped in the water column was investigated, and the isotopic signature (εNd(0)=3.9, 87Sr/86Sr=0.70434) is differentiated from long-range transported dust originating from South America and Australia. Elevated lithogenic accumulation rates in deeper sediment traps in the Ross Sea suggest that sinking particles in the water column cannot simply result from dust input at the surface. This discrepancy can be best explained by significant upwelling and remobilization of lithogenic Fe from the sea floor.

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Gaye, B., M. G. Wiesner, and N. Lahajnar. "Nitrogen sources in the South China Sea, as discerned from stable nitrogen isotopic ratios in rivers, sinking particles, and sediments." Marine Chemistry 114, no. 3-4 (May 2009): 72–85. http://dx.doi.org/10.1016/j.marchem.2009.04.003.

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Park, Yu-Hyeon, Hyung Jeek Kim, Ju Won Son, Chan Min Yoo, and Boo-Keun Khim. "Biomarker-based Seawater Temperatures of Winter Sinking Particles and Core-top Sediment in the Ulleung Basin of the East Sea." Ocean Science Journal 54, no. 3 (August 23, 2019): 487–95. http://dx.doi.org/10.1007/s12601-019-0017-7.

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32

FRIGNANI, M., F. GIGLIO, A. ACCORNERO, L. LANGONE, and M. RAVAIOLI. "Sediment characteristics at selected sites of the Ross Sea continental shelf: does the sedimentary record reflect water column fluxes?" Antarctic Science 15, no. 1 (February 19, 2003): 133–39. http://dx.doi.org/10.1017/s0954102003001123.

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Flux data from moored sediment trap experiments and mass accumulation rates in sediments were obtained for three sites in the Ross Sea which are currently studied for the formation and transit of High Salinity Shelf Water and Ice Shelf Water. These two data sets were compared to obtain inferences on the coupling between water column processes and sedimentary records. The depth distribution of physical features and concentrations of organic carbon and biogenic silica in box cores and gravity cores were studied. Mass accumulation rates, established on the basis of two conventional 14C dates for each core, range between 7.64 and 19.46 g m−2 yr−1. Although these are productive areas, downward fluxes measured by sediment traps are low: 7.5–25.6, 2.4–17.9 and 0.5–0.9 g m−2 yr−1 for particles, biogenic silica and organic carbon, respectively. The concentrations of biogenic components in surficial sediments are correspondingly low. Simple mass balances were calculated assuming the conservative behaviour of the lithic fraction of sinking materials and sediment. Lateral advection of suspended particles is needed to balance the fluxes at the three sites. Furthermore, the model suggests that the preservation of biogenic components is lower than at other sites of the Ross Sea, probably due to the low accumulation rates that imply a high residence time of biogenic materials at the sediment-water interface.

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Seeberg-Elverfeldt, I. A., C. B. Lange, J. Pätzold, and G. Kuhn. "Laminae type and possible mechanisms for the formation of laminated sediments in the Shaban Deep, northern Red Sea." Ocean Science 1, no. 2 (October 25, 2005): 113–26. http://dx.doi.org/10.5194/os-1-113-2005.

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Abstract. Laminated sediments in the Shaban Deep, a brine-filled basin in the northern Red Sea, were analyzed with backscattered electron imagery. Here we present possible mechanisms involved in the formation of laminae of various types and homogenous intervals arising from the detailed investigation of multicore GeoB 7805-1 (26°13.9' N and 35°22.6' E; water depth 1447 m) and gravity core GeoB 5836-2 (26°12.61' N, 35°21.56' E; water depth 1475 m). Sediment makeup includes six types: a) a laminated structure with alternating light (mainly coccoliths) and dark (diatom frustules) layers, where the diatom component is indicative of the intra-annual variability between stratification and mixing events; b) a pocket-like structure attributed to the sinking of particles within fecal pellets and aggregates; c) a matrix of tightly packed diatoms that relates to extended stratification/mixing periods of the water column; d) homogenous intervals that result from turbidity deposition; e) silt accumulations which origin may lie in agglutinated foraminifers; and f) pyrite layers with pyrite formation initiated at the seawater-brine interface.

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Seeberg-Elverfeldt, I. A., C. B. Lange, J. Pätzold, and G. Kuhn. "Laminae type and possible mechanisms for the formation of laminated sediments in the Shaban Deep, northern Red Sea." Ocean Science Discussions 2, no. 4 (July 15, 2005): 331–62. http://dx.doi.org/10.5194/osd-2-331-2005.

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Abstract. Laminated sediments in the Shaban Deep, a brine-filled basin in the northern Red Sea, were analyzed with backscattered electron imagery. Here we present possible mechanisms involved in the formation of laminae of various types and homogenous intervals arising from the detailed investigation of multicore GeoB 7805-1 (26 13.9' N and 35 22.6' E; water depth 1447 m) and gravity core GeoB 5836-2 (26 12.61' N, 35 21.56' E; water depth 1475 m). Sediment makeup includes six types: a) a laminated structure with alternating light (mainly coccoliths) and dark (diatom frustules) layers, where the diatom component is indicative of the intra-annual variability between stratification and mixing events; b) a pocket-like structure attributed to the sinking of particles within fecal pellets and aggregates; c) a matrix of tightly packed diatoms that relates to extended stratification/mixing periods of the water column; d) homogenous intervals that result from turbidity deposition; e) silt accumulations which origin may lie in agglutinated foraminifers; and f) pyrite layers with pyrite formation initiated at the seawater-brine interface.

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Möbius, J., N. Lahajnar, and K. C. Emeis. "Diagenetic control of nitrogen isotope ratios in Holocene sapropels and recent sediments from the Eastern Mediterranean Sea." Biogeosciences Discussions 7, no. 1 (February 17, 2010): 1131–65. http://dx.doi.org/10.5194/bgd-7-1131-2010.

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Abstract. The enhanced accumulation of organic matter in Eastern Mediterranean sapropels and their unusually depleted δ15N values have been attributed to either enhanced nutrient availability which led to elevated primary production and carbon sequestration or to enhanced organic matter preservation under anoxic conditions. In order to evaluate these two hypothesis we have determined Ba/Al ratios, amino acid composition, N and organic C concentrations and δ15N on sinking particles, surface sediments, eight spatially distributed core records of the youngest sapropel S1 (10-6 ka) and older sapropels (S5, S6) from two locations. These data suggest that (i) temporal and spatial variations in δ15N of sedimentary N are driven by different degrees of diagenesis at different sites rather than by changes in N-sources or primary productivity and (ii) that present day TOC export production would suffice to create a sapropel like S1 under conditions of deep-water anoxia. This implies that both enhanced TOC accumulation and δ15N depletion in sapropels were due to the absence of oxygen in deep waters. Thus preservation plays a major role for the accumulation of organic-rich sediments casting doubt the need of enhanced primary production for sapropel formation.

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Möbius, J., N. Lahajnar, and K. C. Emeis. "Diagenetic control of nitrogen isotope ratios in Holocene sapropels and recent sediments from the Eastern Mediterranean Sea." Biogeosciences 7, no. 11 (November 30, 2010): 3901–14. http://dx.doi.org/10.5194/bg-7-3901-2010.

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Abstract. The enhanced accumulation of organic matter in Eastern Mediterranean sapropels and their unusually low δ15N values have been attributed to either enhanced nutrient availability which led to elevated primary production and carbon sequestration or to enhanced organic matter preservation under anoxic conditions. In order to evaluate these two hypothesis we have determined Ba/Al ratios, amino acid composition, N and organic C concentrations and δ15N in sinking particles, surface sediments, eight spatially distributed core records of the youngest sapropel S1 (10–6 ka) and older sapropels (S5, S6) from two locations. These data suggest that (i) temporal and spatial variations in δ15N of sedimentary N are driven by different degrees of diagenesis at different sites rather than by changes in N-sources or primary productivity and (ii) present day TOC export production would suffice to create a sapropel like S1 under conditions of deep-water anoxia. This implies that both enhanced TOC accumulation and δ15N depletion in sapropels were due to the absence of oxygen in deep waters. Thus preservation plays a major role for the accumulation of organic-rich sediments casting doubt on the need of enhanced primary production for sapropel formation.

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37

NAYA, Tomonori, Yoshihiro TANIMURA, Taku TSUCHIYA, Hideto ABEKAWA, Ryoji NAKAZATO, and Kazuo AMANO. "Behavior of sinking particles and depositional processes of diatom frustules in shallow lake, examined by sediment trap in Lake Kitaura, central Japan." Japanese Journal of Limnology (Rikusuigaku Zasshi) 65, no. 3 (2004): 203–13. http://dx.doi.org/10.3739/rikusui.65.203.

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38

Takahashi, Nobuyuki, and Shinichiro Noriki. "Rare earth elements and Opal/CaCO3 ratio of sinking particles observed with a time-series sediment trap at the mouth of Tokyo Bay." Journal of Oceanography 63, no. 6 (December 2007): 941–51. http://dx.doi.org/10.1007/s10872-007-0079-5.

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39

Honda, Makio C., Hajime Kawakami, Kazuhiko Matsumoto, Masahide Wakita, Tetsuichi Fujiki, Yoshihisa Mino, Chiho Sukigara, et al. "Comparison of sinking particles in the upper 200 m between subarctic station K2 and subtropical station S1 based on drifting sediment trap experiments." Journal of Oceanography 72, no. 3 (March 26, 2015): 373–86. http://dx.doi.org/10.1007/s10872-015-0280-x.

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40

Abramson, Lynn, Cindy Lee, Zhanfei Liu, Stuart G. Wakeham, and Jennifer Szlosek. "Exchange between suspended and sinking particles in the northwest Mediterranean as inferred from the organic composition of in situ pump and sediment trap samples." Limnology and Oceanography 55, no. 2 (February 1, 2010): 725–39. http://dx.doi.org/10.4319/lo.2010.55.2.0725.

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41

Ran, Lihua, Jianfang Chen, Martin G. Wiesner, Zheng Ling, Niko Lahajnar, Zhi Yang, Hongliang Li, Qiang Hao, and Kui Wang. "Variability in the abundance and species composition of diatoms in sinking particles in the northern South China Sea: Results from time-series moored sediment traps." Deep Sea Research Part II: Topical Studies in Oceanography 122 (December 2015): 15–24. http://dx.doi.org/10.1016/j.dsr2.2015.07.004.

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42

Siegel, D. A., and R. A. Armstrong. "Corrigendum to “Trajectories of sinking particles in the Sargasso Sea: modeling of statistical funnels above deep-ocean sediment traps” [Deep-Sea Research I 44, 1519–1541]." Deep Sea Research Part I: Oceanographic Research Papers 49, no. 6 (June 2002): 1115–16. http://dx.doi.org/10.1016/s0967-0637(02)00007-9.

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43

Dubovskaya, Olga P., Aleksander P. Tolomeev, and Zhanna F. Busevac. "The Methodology of Using Sediment Traps to Study Vertical Flux and Sinking Velocities of Suspended Particles of Large Size: Marine Snow, Fecal Pellets and Zooplankton Carcasses (a Review)." Journal of Siberian Federal University. Biology 10, no. 3 (September 2017): 269–300. http://dx.doi.org/10.17516/1997-1389-0001.

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44

Gehlen, M., L. Bopp, N. Emprin, O. Aumont, C. Heinze, and O. Ragueneau. "Reconciling surface ocean productivity, export fluxes and sediment composition in a global biogeochemical ocean model." Biogeosciences 3, no. 4 (November 9, 2006): 521–37. http://dx.doi.org/10.5194/bg-3-521-2006.

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Abstract. This study focuses on an improved representation of the biological soft tissue pump in the global three-dimensional biogeochemical ocean model PISCES. We compare three parameterizations of particle dynamics: (1) the model standard version including two particle size classes, aggregation-disaggregation and prescribed sinking speed; (2) an aggregation-disaggregation model with a particle size spectrum and prognostic sinking speed; (3) a mineral ballast parameterization with no size classes, but prognostic sinking speed. In addition, the model includes a description of surface sediments and organic carbon early diagenesis. Model output is compared to data or data based estimates of ocean productivity, pe-ratios, particle fluxes, surface sediment bulk composition and benthic O2 fluxes. Model results suggest that different processes control POC fluxes at different depths. In the wind mixed layer turbulent particle coagulation appears as key process in controlling pe-ratios. Parameterization (2) yields simulated pe-ratios that compare well to observations. Below the wind mixed layer, POC fluxes are most sensitive to the intensity of zooplankton flux feeding, indicating the importance of zooplankton community composition. All model parameters being kept constant, the capability of the model to reproduce yearly mean POC fluxes below 2000 m and benthic oxygen demand does at first order not dependent on the resolution of the particle size spectrum. Aggregate formation appears essential to initiate an intense biological pump. At great depth the reported close to constant particle fluxes are most likely the result of the combined effect of aggregate formation and mineral ballasting.

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Sañé, E., J. Martín, P. Puig, and A. Palanques. "Organic biomarkers in deep-sea regions affected by bottom trawling: pigments, fatty acids, amino acids and carbohydrates in surface sediments from the La Fonera (Palamós) Canyon, NW Mediterranean Sea." Biogeosciences Discussions 9, no. 12 (December 18, 2012): 18601–54. http://dx.doi.org/10.5194/bgd-9-18601-2012.

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Abstract. Deep-sea ecosystems are in general adapted to a limited variability of physical conditions, resulting in high vulnerability and slow recovery rates from anthropogenic perturbations such as bottom trawling. Commercial trawling is the most recurrent and pervasive of human impacts on the deep-sea floor, but studies on its consequences on the biogeochemistry of deep-sea sediments are still scarce. Pigments, fatty acids, amino acids and carbohydrates were analyzed in sediments from the flanks of the La Fonera (Palamós) submarine canyon (NW Mediterranean Sea), where a commercial bottom trawling fishery has been active for more than 70 yr. More specifically, we investigated how trawling-induced sediment reworking affects the quality of sedimentary organic matter which reaches the seafloor and accumulates in the sediment column, which is fundamental for the development of benthic communities. Sediment samples were collected during two oceanographic cruises in spring and autumn 2011. The sampled sites included trawl fishing grounds as well as pristine (control) areas. We report that bottom trawling in the flanks of the La Fonera Canyon has caused an alteration of the quality of the organic matter accumulated in the upper 5 cm of the seafloor. The use of a wide pool of biochemical tracers characterized by different reactivity to degradation allowed us to discriminate the long-term effects of trawled-induced sediment reworking from the natural variability caused by the seasonal cycle of production and sinking of biogenic particles. Differences between untrawled and trawled areas were evidenced by labile amino acids, while differences between spring and autumn samples were detected only by the more labile indicators chlorophyll a and mono-unsaturated fatty acids. These results suggest that changes in the biochemical composition of the sedimentary organic matter caused by bottom trawling can be more relevant than those associated with natural seasonality and pose serious concerns about the ecological sustainability of deep-sea trawling activities.

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46

Sañé, E., J. Martín, P. Puig, and A. Palanques. "Organic biomarkers in deep-sea regions affected by bottom trawling: pigments, fatty acids, amino acids and carbohydrates in surface sediments from the La Fonera (Palamós) Canyon, NW Mediterranean Sea." Biogeosciences 10, no. 12 (December 11, 2013): 8093–108. http://dx.doi.org/10.5194/bg-10-8093-2013.

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Abstract. Deep-sea ecosystems are in general adapted to a limited variability of physical conditions, resulting in high vulnerability and slow recovery rates from anthropogenic perturbations such as bottom trawling. Commercial trawling is the most recurrent and pervasive of human impacts on the deep-sea floor, but studies on its consequences on the biogeochemistry of deep-sea sediments are still scarce. Pigments, fatty acids, amino acids and carbohydrates were analysed in sediments from the flanks of the La Fonera (Palamós) submarine canyon (NW Mediterranean Sea), where a commercial bottom trawling fishery has been active for more than 70 yr. More specifically, we investigated how trawling-induced sediment reworking affects the quality of sedimentary organic matter which reaches the seafloor and accumulates in the sediment column, which is fundamental for the development of benthic communities. Sediment samples were collected during two oceanographic cruises in spring and autumn 2011. The sampled sites included trawl fishing grounds as well as pristine (control) areas. We report that bottom trawling in the flanks of the La Fonera Canyon has caused an alteration of the quality of the organic matter accumulated in the upper 5 cm of the seafloor. The use of a wide pool of biochemical tracers characterized by different reactivity to degradation allowed for us to discriminate the long-term effects of trawl-induced sediment reworking from the natural variability caused by the seasonal cycle of production and sinking of biogenic particles. Differences between untrawled and trawled areas were evidenced by labile amino acids, while differences between spring and autumn samples were detected only by the more labile indicators chlorophyll a and monounsaturated fatty acids. These results suggest that changes in the biochemical composition of the sedimentary organic matter caused by bottom trawling can be more relevant than those associated with natural seasonality and pose serious concerns about the ecological sustainability of deep-sea trawling activities.

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47

Gehlen, M., L. Bopp, N. Emprin, O. Aumont, C. Heinze, and O. Ragueneau. "Reconciling surface ocean productivity, export fluxes and sediment composition in a global biogeochemical ocean model." Biogeosciences Discussions 3, no. 3 (June 28, 2006): 803–36. http://dx.doi.org/10.5194/bgd-3-803-2006.

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Abstract. This study focuses on an improved representation of the biological soft tissue pump in the global three-dimensional biogeochemical ocean model PISCES. We compare three parameterizations of particle dynamics: (1) the model standard version including two particle size classes, aggregation-disaggregation and prescribed sinking speed; (2) an aggregation-disaggregation model with a particle size spectrum and prognostic sinking speed; (3) a mineral ballast parameterization with no size classes, but prognostic sinking speed. In addition, the model includes a description of surface sediments and organic carbon early diagenesis. The integrated representation of material fluxes from the productive surface ocean down to the sediment-water interface allows taking advantage of surface ocean observations, sediment trap data and exchange fluxes at the sediment-water interface. The capability of the model to reproduce yearly averaged particulate organic carbon fluxes and benthic oxygen demand does at first order not dependent on the resolution of the particle size spectrum. Model results obtained with the standard version and with the one including a particle size spectrum and prognostic sinking speed are not significantly different. Both model versions overestimate particulate organic carbon between 1000 and 2000 m, while deep fluxes are of the correct order of magnitude. Predicted benthic oxygen fluxes correspond with respect to their large scale distribution and magnitude to data based estimates. Modeled particulate organic C fluxes across the mesopelagos are most sensitive to the intensity of zooplankton flux feeding. An increase of the intensity of flux feeding in the standard version results in lower mid- and deep-water particulate organic carbon fluxes, shifting model results to an underestimation of particulate organic carbon fluxes in the deep. The corresponding benthic oxygen fluxes are too low. The model version including the mineral ballast parameterization yields an improved fit between modeled and observed particulate organic carbon fluxes below 2000 m and down to the sediment-water interface. Our results suggest that aggregate formation alone might not be sufficient to drive an intense biological pump. The later is most likely driven by the combined effect of aggregate formation and mineral ballasting.

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Siegel, David A., Timothy C. Granata, Anthony F. Michaels, and Tommy D. Dickey. "Mesoscale eddy diffusion, particle sinking, and the interpretation of sediment trap data." Journal of Geophysical Research 95, no. C4 (1990): 5305. http://dx.doi.org/10.1029/jc095ic04p05305.

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49

Kawahata, Hodaka, and Hidekazu Ohta. "Sinking and suspended particles in the South-west Pacific." Marine and Freshwater Research 51, no. 2 (2000): 113. http://dx.doi.org/10.1071/mf99057.

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Sinking and suspended particles were sampled at Sites 11 and 12 in the Coral Sea, characterized by low seasonal variation in sea surface temperature (SST), and at Site 13 in the central Tasman Sea with a high range of seasonal SST variation. Sinking particles obtained at Site 12 had low annual mean total mass and organic matter (OM) fluxes with high carbonate content. Mean total mass flux at Site 13 was lower than those obtained around the same latitude of the boreal central Pacific. More carbonate-dominated and opal-depleted plankton communitygenerally characterized the sinking particles in the low to mid latitude of the austral western Pacific. To understand the relationship between sinking and suspended particles, suspended particles were taken in the upper 300 m of the water column. C Organic /N atomic ratios in the suspended particles were generally 7–8, indicating that living organisms contributed a significant proportion. Although organic carbon (OC) flux by sinking particles at Site 13 was more than three times higher than that at Site 12 during May–June 1995, the total particle OC standing stock in the top 100 m was similar from 15ºS to 35ºS, indicating that OM is more recycled at the oligotrophic site 12, whereas higher new production yielded higher export production in the middle latitude site 13.

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Ji, Bingqiang, Qiang Song, Ao Wang, and Qiang Yao. "Critical sinking of hydrophobic micron particles." Chemical Engineering Science 207 (November 2019): 17–29. http://dx.doi.org/10.1016/j.ces.2019.06.009.

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