Biography:

In the past Gerold Wefer has collaborated on articles with Robert B. Dunbar and Rüdiger Henrich. One of their most recent publications is Research paperStable isotope fractionation in benthic foraminifera from the Peruvian continental margin. Which was published in journal Marine Geology.

More information about Gerold Wefer research including statistics on their citations can be found on their Copernicus Academic profile page.

Gerold Wefer's Articles: (18)

Research paperStable isotope fractionation in benthic foraminifera from the Peruvian continental margin

AbstractStable isotope ratios of the carbonate tests of benthic foraminifera are now widely used to reconstruct past changes in ocean circulation and chemistry. Such studies depend on the accuracy with which changing environmental conditions are recorded and preserved in the tests of foraminifera found in deep-sea deposits. Assessment of this aspect of the method is best accomplished through rigorous study of modern core-tops collected from a wide range of depths and bottom water temperatures. Stable isotope analyses of eighteen taxa of benthic foraminifera from surface sediments of the Peru continental margin indicate that most foraminifera are slightly depleted in 18O relative to the benthic foram Uvigerina peregrina. For at least five taxa we observed subparallel δ18O-temperature relationships with slopes nearly equal to that predicted by Shackleton (1974) for Uvigerina. For seven taxa, isotopic analysis of six size fractions (in the range 210–>590 mm) reveals that, with the exception of U. peregrina, variation between different size classes for each species is small, <0.35‰) for δ18O and <0.5‰) for δ13C. A slight inverse correlation between foraminiferal 18O and 13C content implies a complex interplay of biological and environmental factors which control isotopic composition.

Research paperDissolution of biogenic carbonates: Effects of skeletal structure

AbstractDissolution of biogenic shallow-water carbonates exposed on deep-sea moorings indicates that skeletal structure is important for the rate of disintegration of biogenic carbonates, besides mineralogy and grain size of particles. The aragonites and high Mg-calcites used represent a wide spectrum of mineralogies and types of skeletal framework. The particles were deployed at different water depths on a mooring in the Drake Passage for 52 days.Weight loss curves for the various types of particles show the relative importance of the different structural factors for the disintegration of these biogenic carbonates.Organic coatings, intraskeletal pore spaces, and sizes and shapes of individual crystallites in the skeletons may be more important than carbonate mineralogy and particle size in cases. The presence of internal sediments, cement aggregates and natural contaminations and of diatoms incorporated during growth into carbonate skeletons, strongly influence the disintegration of the skeletal materials.The first step of particle disintegration is the selective removal of impurities. This step is analogous to a “cleaning” of specimens. It is succeeded by initial dissolution, by strong dissolution and finally by disintegration.

Regular research paperIsotope paleontology: growth and composition of extant calcareous species

AbstractIsotope paleontology uses the isotopic composition of fossil remains of organisms to make inferences about the physical surroundings of growth of the organisms (especially temperature), and to obtain clues about life history and modes of growth. In calcareous fossils, oxygen isotopes are mainly used in the former, and carbon isotopes in the latter. However, since physical surroundings and organism response are intimately associated, both types of information are contained in each of the isotopic signals. To explore the potential of isotope paleontology, and to provide a basis for reconstruction, a broad range of extant organisms has been studied, taking the pioneering work of Epstein and associates as a starting point. Results are summarized for a representative sampling of these studies, with emphasis on work at the laboratories of the authors, from the mid-seventies to the present. The organisms considered are nannoplankton, benthic algae, planktonic and benthic deep-sea foraminifera, “larger” foraminifera, sponges, corals, bryozoans, polychaetes, arthropods, bivalves, gastropods, cephalopods, and vertebrates (fish otoliths). The survey broadly suggests that, regarding oxygen isotopes, materials tend to be precipitated close to equilibrium with the surrounding seawater (as postulated by Urey), and that for carbon isotopes disequilibrium is the rule. Life spans, growth rates, differential seasonal growth, and age of reproductive activity can be extracted under favorable circumstances from individual shells and skeletal parts. In detail, the interpretation of isotope records of individual shells is quite complicated, and simple models will fail to give satisfactory results in many or most cases.

Stable isotopes in recent larger foraminifera

AbstractOxygen and carbon isotope analyses have been made on large benthic foraminifera from Bermuda, the Persian Gulf, and the Philippines. The foraminifera belong to the two suborders Rotallina and Miliolina. Life spans range between one season to more than two years. Shells contain information about seasonal temperature ranges and life-history stages, recorded as fluctuations of oxygen and carbon isotopic values within the shell material. Almost all specimens studied showed the expected variations in δ 18O with respect to ambient conditions (water isotopic composition and seasonal temperature fluctuations). The specimens from Bermuda seemed enriched in 18O, whereas all specimens from the Philippines, independent of their taxonomic position, seemed to the depleted in 18O with respect to calcita equilibrium. Specimens from the same species showed about the same level and range of δ 18O values. The miliolid species Marginopora vertebralis, Cyclorbiculina compressa, Archaias angulatus, Peneroplis proteus, and Praesorites orbitolitoides cf. monensis commonly show carbon isotope values up to 2.5‰ lighter than expected equilibrium values independent of sample locality. The rotaliid species Heterostegina depressa, Operculina sp., and Calcarina spengleri show carbon isotope values more than 2‰ lighter than expected equilibrium values, also independent of sample locality. All analyzed miliolid species show a tendency, with age, towards lighter-than-equilibrium δ 13C values. The analyzed rotaliid species showed the reverse, that is, shells tend toward increased δ 13 values with age.

Late Quaternary paleoproductivity changes off the Congo deduced from stable carbon isotopes of planktonic foraminifera

AbstractA detailed record (≈2-kyr intervals) of the difference in stable carbon isotopes (Δδ13C) between Globigerina bulloides and Globigerinoides ruber (pink) is used to reconstruct changes in upwelling intensity off the Congo River for the last 190,000 yr. Comparisons of the oxygen and carbon isotope data from this core with records from the Niger Fan and from pelagic cores in the eastern equatorial South Atlantic indicate that the Congo Fan isotope records do not contain a strong freshwater signal as is described off other major rivers. The temporal pattern of the Δδ13C signal correlates with the marine organic carbon record from the Congo Fan. Thus the planktonic Δδ13C record, reflecting past changes in upwelling intensity and nutrient content, corroborates the signal provided by sedimentary organic carbon, which is presumed to indicate changes in the amount of biological productivity and export flux to the seafloor.The planktonic Δδ13C signal is characterized by a dominant 23-kyr periodicity which provides evidence for a strong response of upwelling fluctuations off the Congo to precessional forcing. Minima in the Δδ13C record are aligned with periods of minimum boreal summer insolation over Central Africa reflecting an increase of upwelling and biological productivity off the Congo at periods of enhanced zonal intensity of southeast trades and corresponding weak southeast monsoon over the eastern South Atlantic. A strong response to changes in river discharge probably did not occur, indicating that fertilization by river-derived nutrients has played only a minor role with respect to Late Quaternary changes in the total amount of primary productivity off the Congo.

Rapid response paperSeasonal particle flux in the Bransfield Strait, Antartica

AbstractTime-series sediment traps were deployed at 494 and 1588 m water depth in Bransfield Strait from 1 December, 1983 to 25 November, 1984. During austral summer (December and January) total flux was more than 1.5 g m−2 day−1 to both water depths, while during all other months 1984 flux was between 10 and 1000 times lower. The annual total flux to the deeper trap (1588 m) was 110 g m−2. The flux of the two most productive months was 97% of the total. Biogenic components (carbonate, POM and opaline silica) accounted for about 67% in the upper trap and 50% in the lower one. The remaining portion of the material collected were lithogenic particles. The transfer of the particles is mainly through the fecal pellets of krill.

Holocene rainfall variability in southern Chile: a marine record of latitudinal shifts of the Southern Westerlies

AbstractGeochemical and clay mineral parameters of a high accumulation marine sediment core from the Chilean continental slope (41°S) provide a 7700 yr record of rainfall variability in southern Chile related to the position of the Southern Westerlies. We especially use the iron content, measured with a time-resolution of ca. 10 yr on average, of 14C-accelerator mass spectrometry dated marine sediments as a proxy for the relative input of iron-poor Coastal Range and iron-rich Andean source rocks. Variations in this input are most likely induced by rainfall changes in the continental hinterland of the core position. Based on these interpretations, we find a pronounced rainfall variability on multi-centennial to millennial time-scales, superimposed on generally more arid conditions during the middle Holocene (7700 to 4000 cal yr B.P.) compared to the late Holocene (4000 to present). This variability and thus changes in the position of the Southern Westerlies are first compared to regional terrestrial paleoclimate data-sets from central and southern Chile. In order to derive possible wider implications and forcing mechanisms of the Holocene latitudinal shifts of the Southern Westerlies, we then compare our data to ice-core records from both tropical South America and coastal Antarctica. These records show similar bands of variability centered at ca. 900 and 1500 yr. Comparisons of band pass filters suggest a close connection of shifts of the Southern Westerlies to changes within the tropical climate system. The correlation to climate conditions in coastal Antarctica shows a more complicated picture with a phase shift at the beginning of the late Holocene coinciding with the onset of the modern state of El Niño-Southern Oscillation system. The presented data provide further evidence that the well known millennial-scale climate variability during the last glacial continued throughout the Holocene.

Interhemispheric comparison of deglacial sea-surface temperature patterns in Atlantic eastern boundary currents

AbstractSediment core GeoB 1023-5 from the eastern South Atlantic was investigated at high temporal resolution for variations of sea-surface temperature (SST) during the past 22 kyr, using the alkenone (UK′37) method. SSTs increased by 3.5°C from about 18°C during the Last Ice Age (21±2 cal kyr BP) to about 21.5°C at 14.5 cal kyr BP. This warming trend associated with the deglaciation phase was followed by a cooling event with lowest SSTs near 20°C, persisting for about 1000 years between 13 and 12 cal kyr BP. The SSTs then continued to increase to about 22.5°C at the Holocene climatic optimum at 7 cal kyr BP, and decreased again during the Late Holocene to a core-top value of 19.8°C that is comparable to modern annual mean SST values. When compared with alkenone SST records from the eastern North Atlantic, our SST record indicates continuous warming throughout the deglaciation phase in the Benguela Current, while its northern counterpart, the Canary Current, experienced prominent cooling during ‘Heinrich Event 1’ (H1). On the other hand, for the time period corresponding to the ‘Younger Dryas’ (YD) cooling event, the Benguela SST record exhibits a cold-temperature interval that corresponds to that observed in the eastern North Atlantic SST records. This observation suggests that interhemispheric climate response in Atlantic eastern boundary current systems was different with respect to the two abrupt climate events associated with Termination I. For the H1, the eastern South Atlantic SST record strongly supports the hypothesis that an ‘anti-phase’ thermal behavior in South Atlantic surface waters was forced by the slowdown of the North Atlantic Deep Water formation during cold spells in the North Atlantic. In contrast, the abrupt cooling in the eastern South Atlantic coincident with the YD period was probably induced by more vigorous global atmospheric circulation, enhancing the upwelling intensity in both eastern boundary current systems. This atmospheric control may have overridden any effect caused by changes in thermohaline circulation on the South Atlantic SSTs during the YD, which leads to the assumption that the thermohaline circulation was already much closer to its interglacial mode during the YD than during the H1.

Late glacial to Holocene paleoenvironmental evolution of the Black Sea, reconstructed with stable oxygen isotope records obtained on ostracod shells

AbstractHigh-resolution stable oxygen isotope (δ18O on ostracod shells), XRF-scanning and bulk grain-size data obtained on a transect of 6 gravity cores from the continental slope in the northwestern Black Sea give new insight into the hydrological evolution of the Black Sea since the Last Glacial Maximum (LGM). Stable climatic conditions during the LGM were followed by a series of meltwater pulses between 18 and 15.5 kyr BP that resulted in temporary isotopic depletion of the Black Sea waters. Subsequently, steadily increasing δ18O values in all cores are mainly caused by isotopically enriched precipitation at the onset of the Allerød/Bølling warm period. A comparison of the major trends in δ18O at different water depths suggests evaporation-driven deep water formation since ∼14.5 kyr BP, while the two shallowest cores from 168 and 465 m water depth were under the influence of increased warming in the upper water column since 14.5 and 12.5 kyr BP, respectively. The core from 168 m depth seems to be additionally influenced by freshwater input of the Danube. This core provides a high-resolution record from the Younger Dryas/Allerød boundary and suggests that a NAO-like climate mode was governing the interannual variability in the run-off of the Danube, which implies that this climate mode has been a persistent climatic feature over central Europe. The inflow of saline Mediterranean waters occurs between 9 and 8 kyr BP, where a merging of all δ18O records signals an initial homogenisation of the water column.

Late Quaternary δ13C gradients and carbonate accumulation in the western equatorial Atlantic

AbstractWe investigated glacial–interglacial changes in vertical δ13C gradients in the western equatorial Atlantic using the carbon isotopic composition of planktonic and benthonic foraminifera. Core top measurements show that the δ13C difference between shallow-dwelling G. sacculifer and thermocline-dwelling G. truncatulinoides is an indicator of the vertical nutrient gradient in the upper water column. In the western equatorial Atlantic, the δ13C differences between G. sacculifer and G. truncatulinoides are reduced during glacials and cold substages of interglacials, while the δ13C differences between G. truncatulinoides and the benthonic species C. wuellerstorfi are increased. This indicates that nutrients were depleted in the thermocline and enriched in deep waters during cold substages. Covariance between the δ13C records of G. truncatulinoides from the western equatorial Atlantic and C. wuellerstorfi from Caribbean intermediate water suggests that the upper part of the western equatorial Atlantic water column was largely composed of nutrient-poor central and intermediate waters of northern origin. This pattern might have been the result of a circulation mode in which subantarctic surface waters formed nutrient-rich deep waters rather than intermediate waters. Lower 230Th-normalized carbonate accumulation rates during cold substages imply that the decreased nutrient content of subsurface waters induced a lower primary productivity in the western equatorial Atlantic.

Recent distribution of planktonic foraminifera in the Nansen Basin, Arctic Ocean

AbstractPlanktonic foraminifera were collected in the Arctic Ocean with net tows (>63 μin) along a S-N transect from 81 to 86°N. Five depth intervals were sampled vertically between 500 m water depth and the sea surface. The most common species are Neogloboquadrina pachyderma and Globigerina quinqueloba. Based on the depth habitat, the faunal composition and the population structure, the planktonic foraminifera can be divided into two distinct provinces having a latitudinal boundary at 83°N. In the southern area, the concentrations of planktonic foraminifera are highest as well as the per cent of subpolar species and right-coiling individuals. Both species prefer the water below the pycnocline at about 100 m. North of 83°N, the two species display maximum abundance in the upper 50 m, where the water is colder and fresher than below the pycnocline. The proportions of right-coiling individuals and subpolar species are decreasing going northward. The observed changes are caused by the input of Atlantic water masses transported into the Arctic Ocean.

Orbital- and millennial-scale changes in the hydrologic cycle and vegetation in the western African Sahel: insights from individual plant wax δD and δ13C

AbstractTo reconstruct variability of the West African monsoon and associated vegetation changes on precessional and millennial time scales, we analyzed a marine sediment core from the continental slope off Senegal spanning the past 44,000 years (44 ka). We used the stable hydrogen isotopic composition (δD) of individual terrestrial plant wax n-alkanes as a proxy for past rainfall variability. The abundance and stable carbon isotopic composition (δ13C) of the same compounds were analyzed to assess changes in vegetation composition (C3/C4 plants) and density. The δD record reveals two wet periods that coincide with local maximum summer insolation from 38 to 28 ka and 15 to 4 ka and that are separated by a less wet period during minimum summer insolation. Our data indicate that rainfall intensity during the rainy season throughout both wet humid periods was similar, whereas the length of the rainy season was presumably shorter during the last glacial than during the Holocene. Additional dry intervals are identified that coincide with North Atlantic Heinrich stadials and the Younger Dryas interval, indicating that the West African monsoon over tropical northwest Africa is linked to both insolation forcing and high-latitude climate variability. The δ13C record indicates that vegetation of the western Sahel was consistently dominated by C4 plants during the past 44 ka, whereas C3-type vegetation increased during the Holocene. Moreover, we observe a gradual ending of the Holocene humid period together with unchanging ratio of C3 to C4 plants, indicating that an abrupt aridification due to vegetation feedbacks is not a general characteristic of this time interval.

Distribution of planktic foraminifera at the ice margin in the Arctic (Fram Strait)

AbstractPlanktic foraminifera were collected in net tows (>63 μm) along two east-west transects at 78 ° and 80 °N in the Fram Strait (northern Nordic Seas) at five concurrent depth intervals in the upper 200 m of the water column. In the ice-free zone, absolute abundances in the upper 200 m of the water column up to 500 individuals/m3 were obtained. Along the ice margin the absolute abundances reached up to 1250 ind/m3, while in the ice-covered areas not more than 50 ind/m3 have been found. Surprisingly, these strong variations in abundance are not accompanied by significant changes in faunal assemblages between the ice-free and the ice-covered regions. Neogloboquadrina pachyderma is the dominant species in most samples, making up to 60% of the total faunal assemblage. Globigerina quinqueloba contributes 38%, and all other species combined make up only 2% of the total fauna. Both, absolute and relative abundances of the collected foraminifera are strongly dependent on the mesh size used. Using smaller mesh sizes provides a wider species spectrum, which is of special interest for paleoceanographic reconstructions in the Nordic Seas, where fossil assemblages >150 μm often consist of only one species. The specific hydrographic conditions in the Fram Strait, with warm Atlantic waters underlying cold Polar surface waters, result in a rather atypical depth distribution of the planktic foraminifera. All species seem to prefer the temperate Atlantic waters (between 50 m and 200 m). Thus, the species composition as well as geochemical tracers do not reflect the surface ocean conditions, which again has potentially interesting implications for paleoceanographic reconstructions.

Temperature sensitivity of planktic foraminifera and its influence on the oxygen isotope record

AbstractWe used oxygen isotope measurements from Holocene surface sediments to infer optimum temperature and temperature sensitivity of the planktic foraminiferal species Globigerinoides ruber (pink) and Globigerinoides sacculifer. The (isotopic) optimum temperature of G. ruber (pink) is close to 27°C. G. sacculifer seems to have optimum vital conditions around 22°C and is less temperature sensitive than G. ruber (pink). Our estimations of optimum temperature and temperature sensitivity are in good accordance with laboratory and field investigations. Two simple experiments show that the temperature sensitivity of planktic foraminifera, determined from oxygen isotopes, can influence phase and amplitude of oxygen isotope records, if the temperature distribution at the sea surface changes through time. To use this distortion for paleoceanography, we suggest to derive an ‘isotopic transfer function’ which allows the calculation of average temperature, temperature variability and the isotopic composition of seawater if the oxygen-isotope differences between at least three species are known.

Organic carbon accumulation in the South Atlantic Ocean: its modern, mid-Holocene and last glacial distribution

AbstractA compilation of 1118 surface sediment samples from the South Atlantic was used to map modern seafloor distribution of organic carbon content in this ocean basin. Using new data on Holocene sedimentation rates, we estimated the annual organic carbon accumulation in the pelagic realm (>3000 m water depth) to be approximately 1.8×1012 g C year−1. In the sediments underlying the divergence zone in the Eastern Equatorial Atlantic (EEA), only small amounts of organic carbon accumulate in spite of the high surface water productivity observed in that area. This implies that in the Eastern Equatorial Atlantic, organic carbon accumulation is strongly reduced by efficient degradation of organic matter prior to its burial.During the Last Glacial Maximum (LGM), accumulation of organic carbon was higher than during the mid-Holocene along the continental margins of Africa and South America (Brazil) as well as in the equatorial region. In the Eastern Equatorial Atlantic in particular, large relative differences between LGM and mid-Holocene accumulation rates are found. This is probably to a great extent due to better preservation of organic matter related to changes in bottom water circulation and not just a result of strongly enhanced export productivity during the glacial period. On average, a two- to three-fold increase in organic carbon accumulation during the LGM compared to mid-Holocene conditions can be deduced from our cores. However, for the deep-sea sediments this cannot be solely attributed to a glacial productivity increase, as changes in South Atlantic deep-water circulation seem to result in better organic carbon preservation during the LGM.

Lithogenic particle fluxes and grain size distributions in the deep ocean off northwest Africa: Implications for seasonal changes of aeolian dust input and downward transport

AbstractBetween 1988 and 1994, twenty time-series sediment traps were deployed at different water depths in the Canary Island region, off Cape Blanc (Mauritania), and off Cape Verde (Senegal). Lithogenic particle fluxes and grain size distributions of the carbonate-free fraction of the trapped material show a high impact of dust transported either in the northeast trade winds or the Saharan Air Layer (SAL). Highest annual mean lithogenic fluxes (31.2–56.1 mg m-2 d-1) were observed at the Cape Blanc site, and largest annual mean diameters (>6 μm) were found off Cape Verde (14.5–16.9 μm) and off Cape Blanc (15.2–16.7 μm). Lowest annual lithogenic fluxes (11.4–21.2 mg m-2 d-1 ) and smallest mean diameters (13.5–13.7 μm) occurred in the Canary Island region. A significant correlation of organic carbon and lithogenic fluxes was observed at all sites. Off Cape Blanc, fluxes and mean diameters correlated well between upper (around 1000 m depth) and lower traps (around 3500 m depth), indicating a fast and mostly undisturbed downward transport of particulate matter. In contrast, a major correlation of fluxes without correlating mean diameters occurred in the Canary Island region, which translates into a fast vertical transport plus scavenging of laterally advected material with depth at this site. The seasonality of lithogenic fluxes was highest in the Canary Island region and off Cape Verde, reflecting strong seasonal patterns of atmospheric circulation, with highest occurrence of continental winds in the trade wind layer during winter. In addition, grain size statistics reflect a dominant change of dust transport in the trade winds during winter/spring and transport in the SAL during summer 1993 at the Cape Verde site. Highest lithogenic fluxes during winter were correlated with mean diameters around 10–13 μm, whereas lower fluxes during summer consisted of coarse grains around 20 μm. Annual mean dust input wascalculated from lithogenic fluxes in the range 0.7×106–1.4×106 t yr-1, roughly confirming both sediment accumulation rates and atmospheric model calculations reported previously from this area.

Upwelling intensity and filament activity off Morocco during the last 250,000 years

AbstractThe high-productive upwelling area off Morocco is part of one of the four major trade-wind driven continental margin upwelling zones in the world oceans. While coastal upwelling occurs mostly on the shelf, biogenic particles derived from upwelling are deposited mostly at the upper continental slope. Nutrient-rich coastal water is transported within the Cape Ghir filament region at 30°N up to several hundreds of kilometers offshore. Both upwelling intensity and filament activity are dependent on the strength of the summer Trades. This study is aimed to reconstruct changes in trade wind intensity over the last 250,000 years by the analysis of the productivity signal contained in the sedimentary biogenic particles of the continental slope and beneath the Cape Ghir filament. Detailed geochemical and geophysical analyses (TOC, carbonate, C/N, δ13Corg, δ15N, δ13C of benthic foraminifera, δ18O of benthic and planktic foraminifera, magnetic susceptibility) have been carried out at two sites on the upper continental slope and one site located further offshore influenced by the Cape Ghir filament. A second offshore site south of the filament was analyzed (TOC, magnetic susceptibility) to distinguish the productivity signal related to the filament signal from the general offshore variability. Higher productivity during glacial times was observed at all four sites. However, the variability of productivity during glacial times was remarkably different at the filament-influenced site compared to the upwelling-influenced continental slope sites. In addition to climate-related changes in upwelling intensity, zonal shifts of the upwelling area due to sea-level changes have impacted the sedimentary productivity record, especially at the continental slope sites. By comparison with other proxies related to the strength and direction of the prevailing winds (Si/Al ratio as grain-size indicator, pollen) the productivity record at the filament-influenced site reflects mainly changes in trade-wind intensity. Our reconstruction reveals that especially during glacial times trade-wind intensity was increased and showed a strong variability with frequencies related to precession.

Pollen distribution in the marine surface sediments of the mudbelt along the west coast of South Africa

AbstractThe distribution of pollen in marine surface sediments offshore of the west coast of South Africa has been investigated to aid in the interpretation of marine pollen records of onshore vegetation changes. A transect of sediment surface pollen samples retrieved from the Namaqualand mudbelt from just south of the Orange River mouth (29°S) to St Helena Bay (33°S) indicates distinctive pollen spectra reflecting vegetation communities on the adjacent continent. Pollen concentration increases southwards, partly in relation to greater pollen productivity due to higher biomass and density of fynbos vegetation and of sedimentary processes and low pollen concentrations consequent to dilution with silt and clay from the Orange River. The distribution of specific pollen taxa suggests that the Orange River is a major contributor of pollen to the northern mudbelt declining southwards, while the pollen distribution in the central mudbelt is largely attributable to seasonal inputs of pollen from offshore berg winds and local ephemeral Namaqualand rivers. The typical fynbos elements dominate in the southern mudbelt indicating a pollen source mainly in the fynbos vegetation types. These conclusions support a companion analysis of fossil pollen records of two marine sediment cores from the northern and southern mudbelt respectively. This study demonstrates that pollen records from marine sediment cores in the Namaqualand mudbelt have the potential to be a tool to reconstruct palaeovegetation on the adjacent continent. However, to better reconstruct the palaeoclimate of South Africa and fully understand the relations between terrestrial and marine deposits, more marine surface sediments along the western coast of South Africa as well as more terrestrial surface sediments need to be studied.

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