Long-term vegetation, climate and ocean dynamics inferred from a 73,500 years old marine sediment core (GeoB2107-3) off southern Brazil

Gu, Fang; Zonneveld, Karin A F; Chiessi, Cristiano Mazur; Arz, Helge Wolfgang; Pätzold, Jürgen; Behling, Hermann

doi:10.1016/j.quascirev.2017.06.028

Cited by 57 publications

(67 citation statements)

References 73 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…We infer that local river discharge, and northward intrusions of the PPW analogous to modern winter conditions (Lantzsch et al, ), may also have accounted for the colder and nutrient‐enriched waters at shallower depths. An increased influence of those coastal waters transported by the BCC is suggested by the high Fe/Ca values (Figure c) (Heil, ) and the enhanced percentages of eutrophic dinocysts (Figure d) (Gu et al, ) recorded in our core site. Both proxies have been related to fluvial runoff and continental‐sourced nutrient influx (Gu et al, ).…”

Section: Discussionmentioning

confidence: 54%

“…An increased influence of those coastal waters transported by the BCC is suggested by the high Fe/Ca values (Figure c) (Heil, ) and the enhanced percentages of eutrophic dinocysts (Figure d) (Gu et al, ) recorded in our core site. Both proxies have been related to fluvial runoff and continental‐sourced nutrient influx (Gu et al, ). We would rather expect that higher productivity along the glacial would enhance carbonate content, producing lower Fe/Ca ratios instead.…”

Section: Discussionmentioning

confidence: 54%

“…The investigated section of core GeoB2107‐3 spans the period from 0.85 to 40 cal kyr BP. The age model adopted here is the same as that recently published by Howe, Piotrowski, Noble, et al (), Howe, Piotrowski, Oppo, et al (), Gu et al (), and Portilho‐Ramos et al () using the Marine13 calibration curve (Reimer et al, ), which produced ages similar to those previously published by Hendry et al () using the Marine09 curve (Reimer et al, ). Those age models show a maximum difference of ca.…”

Section: Resultsmentioning

confidence: 72%

“…Marine and terrestrial proxy records from core GeoB2107‐3 compared to other records. (a) Precession‐driven February austral summer insolation (30°S) (Berger, ); (b) stalagmite oxygen isotope record (δ 18 O) from Botuverá Cave (Wang et al, ); (c) major elements intensity (Fe/Ca ratios) from core GeoB2107‐3 (Heil, ); (d) abundance of eutrophic dinocysts from core GeoB2107‐3 (Gu et al, ); as well as of (e) oligotrophic Globigerinoides sacculifer; and both eutrophic (f) Globigerinita glutinata and (g) Globigerina bulloides planktonic foraminifera (this study); (h) Bermuda Rise 231 Pa/ 230 Th records (open squares: McManus et al, ; solid triangles: Lippold et al, ); (i) global sea‐level record (Waelbroeck et al, ). Black symbols at the bottom of the panel depict calibrated radiocarbon ages.…”

Section: Resultsmentioning

confidence: 99%

“…Radiocarbon analyses were conducted at the Leibniz Laboratory for Radiometric Dating and Stable Isotope Research at the University of Kiel, Germany. The age‐depth model was originally published by Hendry et al (), using the Marine09 calibration curve (Reimer et al, ), and more recently by Howe, Piotrowski, Noble, et al (), Howe, Piotrowski, Oppo, et al (), Gu et al (), and Portilho‐Ramos et al () with the Marine13 calibration curve (Reimer et al, ). All radiocarbon ages were converted into calibrated ages using the online version of the software Calib 7.1 (Stuiver et al, ) and the Marine13 calibration curve (Reimer et al, ), applying a marine reservoir correction (Δ R ) of 35 years (Stuiver et al, ; http://calib.org/marine/getref.php?RefNo¼135).…”

Section: Methodsmentioning

confidence: 99%

See 4 more Smart Citations

Productivity Evolution in the South Brazilian Bight During the Last 40,000 Years

Pereira

Arz

Pätzold

et al. 2018

Paleoceanog and Paleoclimatol

Self Cite

View full text Add to dashboard Cite

Marine productivity largely controls the oceanic uptake of atmospheric carbon dioxide and contributed to the global climate changes that led to the termination of the last glacial cycle. Past changes in marine productivity were presumably associated with disturbances in the Atlantic meridional overturning circulation (AMOC). In the South Atlantic, however, the evolution of marine productivity throughout the last glacial–interglacial cycle is still poorly constrained mainly due to the scarcity of records with high temporal resolution. Here we present high‐resolution records of paleoproductivity and upper‐water‐column properties from the western subtropical South Atlantic covering the last 40,000 years. Our records are based on faunal and stable oxygen isotopic analyses of planktonic foraminifera from a marine sediment core collected from an upwelling region off southeastern South America (27°S). We used the relative abundance of eutrophic planktonic foraminifera (i.e., Globigerinita glutinata and Globigerina bulloides) as proxies of primary productivity. Our findings reveal, for the first time, enhanced primary productivity during Heinrich Stadials along the last glacial, when the AMOC showed reduced strength. Additionally, our results reveal decreased primary productivity over the Last Glacial Maximum, a period of markedly lower sea level; and the Younger Dryas, when the AMOC showed only moderate reductions. The most outstanding productivity decline, however, is depicted at the onset of the Holocene, when the AMOC recovers its strength. We hypothesize that the observed changes were triggered by the dynamics of the Brazil Current primarily driven by disturbances in the AMOC.

show abstract

Section: Discussionmentioning

confidence: 54%

Section: Discussionmentioning

confidence: 54%

Section: Resultsmentioning

confidence: 72%

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 3 more Smart Citations

Productivity Evolution in the South Brazilian Bight During the Last 40,000 Years

Pereira

Arz

Pätzold

et al. 2018

Paleoceanog and Paleoclimatol

Self Cite

View full text Add to dashboard Cite

show abstract

Calcium carbonate dissolution triggered by high productivity during the last glacial-interglacial interval at the deep western South Atlantic

Suárez-Ibarra

Frozza

Petró

et al. 2021

Preprint

View full text Add to dashboard Cite

Studies reconstructing surface paleoproductivity and benthic environmental conditions allow us to measure the effectiveness of the biological pump, an important mechanism in the global climate system. In order to assess surface productivity changes and their effect on the seafloor, we studied the sediment core SAT-048A, spanning 43-5 ka, recovered from the continental slope (1,542 m water depth) of the southernmost Brazilian continental margin, deep western South Atlantic. We assessed the sea surface productivity, the organic matter flux to the seafloor, and calcite dissolution effects, based on micropaleontological (benthic and planktonic foraminifers, ostracods), geochemical (benthic δ 13 C isotopes), and sedimentological data (carbonate and bulk sand content). Superimposed on the induced changes related to the last glacial-interglacial transition, the reconstruction indicates a significant and positive correlation between the paleoproductivity proxies and the summer insolation. From the reconstructed data, it was possible to identify high (low) surface productivity, high (low) organic matter flux to the seafloor, and high (low) dissolution rates of planktonic Foraminifera tests during the glacial (postglacial). Furthermore, within the glacial, enhanced productivity was associated with higher insolation values, explained by increased northeasterly summer winds that promoted meandering and upwelling of the nutrient-rich South Atlantic Central Water. Statistical analyses support the idea that productivity is the main cause for seafloor calcium carbonate dissolution, as opposed to changes in the Atlantic Meridional Overturning Circulation (at least for the 25-4 ka period). Further efforts must be invested in the comprehension and quantification of the total organic matter and biogenic carbonate burial during time intervals with an enhanced biological pump, aiming to better understand their individual roles.

show abstract

Climate change shifts the distribution of vegetation types in South Brazilian hotspots

2020

View full text Add to dashboard Cite

Long-term vegetation, climate and ocean dynamics inferred from a 73,500 years old marine sediment core (GeoB2107-3) off southern Brazil

Cited by 57 publications

References 73 publications

Productivity Evolution in the South Brazilian Bight During the Last 40,000 Years

Productivity Evolution in the South Brazilian Bight During the Last 40,000 Years

Calcium carbonate dissolution triggered by high productivity during the last glacial-interglacial interval at the deep western South Atlantic

Climate change shifts the distribution of vegetation types in South Brazilian hotspots

Contact Info

Product

Resources

About