Contrasting vertical distributions of recent planktic foraminifera off Indonesia during the southeast monsoon: implications for paleoceanographic reconstructions

Tapia, Raúl; Ho, Sze Ling; Wang, Hui‐Yu; Groeneveld, Jeroen; Mohtadi, Mahyar

doi:10.5194/bg-2021-329

Cited by 2 publications

(3 citation statements)

References 73 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Ocean productivity (i.e., fluorescence and TOC) and bottom water oxygen content are considered relevant drivers of foraminiferal ecology (Gooday, 2003;Schiebel and Hemleben, 2017). In the case of planktic foraminifera, high ocean productivity generally leads to high foraminiferal abundance due to high food availability (Schiebel and Hemleben, 2017;Tapia et al, 2022). Planktic foraminiferal abundance may coincide with the peak of fluorescence at a certain depth in the water column.…”

Section: Environmental Controls On Foraminiferal Abundance and %Pmentioning

confidence: 99%

“…The production of planktic foraminiferal tests in the water column is generally related to water fertility (Schiebel and Hemleben, 2017;Tapia et al, 2022). Consequently, the oligotrophic Kuroshio Current flowing northward along the eastern coast of Taiwan (Liang et al, 2003) may reduce the planktic foraminiferal abundances and, in turn, the %P in Southern Okinawa Trough.…”

Section: Low Planktic Foraminiferal Abundance and Downslope Sediment ...mentioning

confidence: 99%

See 1 more Smart Citation

Foraminifera as a tool for the reconstruction of paleobathymetry and geohazard: A case study from Taiwan

Tapia¹,

Le²,

Ho³

et al. 2022

Preprint

View full text Add to dashboard Cite

The calcite tests of foraminifera are an important biogenic component of marine sediments. The abundance of foraminiferal tests in marine sediments broadly varies with bathymetry, thus has been used to reconstruct paleobathymetry. It is also promising as a tracer for downslope transport triggered by earthquakes and typhoons, especially if the displaced material from shallow locality contrasts strongly with the background autochthonous sediments in terms of foraminiferal abundance, such as the ratio of benthic and planktic foraminifera termed %P. However, its applicability in sediments off Taiwan has not been assessed. Taiwan is located in the path of typhoons and at tectonic plate margins, where typhoons and earthquakes may trigger submarine geohazards. This, combined with the fact that its seafloor spans a large bathymetric range, render this region an ideal natural laboratory to evaluate the applicability of %P as a proxy for tracing submarine geohazards and bathymetry. Here we report foraminiferal abundance, %P, grain size and elemental data from 148 surface sediment samples off 6 sectors off Taiwan, namely Southern Okinawa Trough, Hoping-Nanao-Hateruma Basins, Taitung-Hualien, Hengchun Ridge, Gaoping, and Changyun Sand Ridge. Of all the hydrographic and sedimentological parameters assessed, seafloor bathymetry is the major driver of foraminiferal abundance and %P in these regions. Notably, several data points deviate from the regional %P-water depth relationship. Based on sedimentological parameters and previous studies, we posit that these outliers may have to do with local sedimentation setting. These processes include earthquake-induced sediment transport via submarine canyon in the Southern Okinawa Trough, typhoon-triggered sediment flushing in Gaoping Canyon, cross-shelf and northward advection of planktic foraminifera on the Gaoping shelf, and carbonate dissolution in deep Hateruma Basin. Off Taiwan, the %P value in sediments increases exponentially with bathymetry (R2 = 0.72), and agrees well with the global calibration obtained by combining 827 data from several regions of the global ocean. The regional %P-water depth relationship may be useful for reconstructing paleobathymetry here, albeit with an uncertainty of ~400 m that increases with bathymetry especially >2000 m. Our results also highlight the potential of the %P index as a tracer for downslope transport and lateral advection in the water column. The downcore application of %P therefore has the potential to reconstruct past geohazard events while also identify autochthonous sediment sequences that are suitable for paleoceanographic reconstruction.

show abstract

Section: Environmental Controls On Foraminiferal Abundance and %Pmentioning

confidence: 99%

Section: Low Planktic Foraminiferal Abundance and Downslope Sediment ...mentioning

confidence: 99%

Foraminifera as a tool for the reconstruction of paleobathymetry and geohazard: A case study from Taiwan

Tapia¹,

Le²,

Ho³

et al. 2022

Preprint

View full text Add to dashboard Cite

show abstract

“…Data availability. Data generated in this study are available in the Supplement and on the PANGAEA database (https://doi.org/10.1594/PANGAEA.941895;Tapia, 2022).…”

mentioning

confidence: 99%

Contrasting vertical distributions of recent planktic foraminifera off Indonesia during the southeast monsoon: implications for paleoceanographic reconstructions

Tapia

Wang

et al. 2022

Biogeosciences

Self Cite

View full text Add to dashboard Cite

Abstract. Planktic foraminifera are widely used in paleoceanographic and paleoclimatic studies. The accuracy of such reconstructions depends on our understanding of the organisms' ecology. Here we report on field observations of planktic foraminiferal abundances (>150 µm) from five depth intervals between 0–500 m water depth at 37 sites in the eastern tropical Indian Ocean. The total planktic foraminiferal assemblage here comprises 29 morphospecies, with 11 morphospecies accounting for 90 % of the total assemblage. Both species composition and dominance in the net samples are broadly consistent with the published data from the corresponding surface sediments. The abundance and vertical distribution of planktic foraminifera are low offshore western Sumatra and increase towards offshore southern Java and the Lesser Sunda Islands (LSI). Average living depth of Trilobatus trilobus, Globigerinoides ruber, and Globigerina bulloides increases eastward, while that of Neogloboquadrina dutertrei, Pulleniatina obliquiloculata, and Globorotalia menardii remains constant. We interpret the overall zonal and vertical distribution patterns in planktic foraminiferal abundances as a response to the contrasting upper-water-column conditions during the southeast monsoon, i.e., oligotrophic and stratified offshore Sumatra (non-upwelling) vs. eutrophic and well mixed offshore Java–LSI (upwelling). Overall, the inferred habitat depths of selected planktic foraminifera species show a good agreement with those from sediment trap samples and from surface sediments off Sumatra, but not with those from surface sediments off Java–LSI. The discrepancy might stem from the different temporal coverage of these sample types. Our findings highlight the need to consider how foraminiferal assemblages and ecology vary on shorter timescales, i.e., from “snapshots” of the water column captured by a plankton net to seasonal and interannual variability as recorded in sediment traps, and how these changes are transferred and preserved in deep-sea sediments.

show abstract

Contrasting vertical distributions of recent planktic foraminifera off Indonesia during the southeast monsoon: implications for paleoceanographic reconstructions

Cited by 2 publications

References 73 publications

Foraminifera as a tool for the reconstruction of paleobathymetry and geohazard: A case study from Taiwan

Foraminifera as a tool for the reconstruction of paleobathymetry and geohazard: A case study from Taiwan

Contrasting vertical distributions of recent planktic foraminifera off Indonesia during the southeast monsoon: implications for paleoceanographic reconstructions

Contact Info

Product

Resources

About