Distribution Of Dinoflagellate Cysts Research Articles

Biostratigraphy of the Bajocian–Bathonian boundary beds in the basin of the Bolshoi Zelenchuk River (Northern Caucasus)

The study of ammonites from the upper part of the upper Bajocian and lower part of the lower Bathonian in the sections of the basin of the Bolshoi Zelenchuk (Karachay-Cherkessia) allowed the recognition of Beds with Parkinsonia djanelidzei (approximate equivalent of the middle part of the Parkinsonia parkinsoni Chronozone) and Beds with Oraniceras scythicum (lower part of the Zigzagiceras zigzag Chronozone). The taxonomic composition and distribution of foraminifers, ostracodes, dinoflagellate cysts, and miospores were studied in the samples from these deposits (upper part of the upper member of Djangura Formation). The recognized characteristic assemblages of microfauna and palynomorphs allowed ostracode and dinocyst subdivisions to be proposed for the Bajocian–Bathonian boundary beds of the Northern Caucasus for the first time. The most important taxa, including ammonites, foraminifers, ostracodes, and dinocysts, are illustrated.

Atlas of modern dinoflagellate cyst distributions in the Black Sea Corridor: from Aegean to Aral Seas, including Marmara, Black, Azov and Caspian Seas

Abstract We present the first comprehensive taxonomic and environmental study of dinoflagellate cysts in 185 surface sediment samples from the Black Sea Corridor (BSC) which is a series of marine basins extending from the Aegean to the Aral Seas (including Marmara, Black, Azov and Caspian Seas). For decades, these low-salinity, semi-enclosed or endorheic basins have experienced large-scale changes because of intensive agriculture and industrialisation, with consequent eutrophication and increased algal blooms. The BSC atlas data provide a baseline for improved understanding of linkages between surface water conditions and dinoflagellate cyst (dinocyst) distribution, diversity and morphological variations. By cross-reference to dinocyst occurrences in sediment cores with radiocarbon ages covering the past c. 11,700 years, the history of recent biodiversity changes can be evaluated. The seabed cyst samples integrate seasonal and multi-year data which are not usually captured by plankton samples, and the cyst composition can point to presence of previously unrecorded motile dinoflagellate species in the BSC. Results show the presence of at least 71 dinocyst taxa of which 36% can be related to motile stages recorded in the plankton. Comparison with sediment core records shows that five new taxa appear to have entered or re-entered the region over the past century. Statistical analysis of the atlas data reveals the presence of four ecological assemblages which are primarily correlated with seasonal and annual surface water salinity and temperature; correlation with phosphate, nitrate and silicate nutrients, chlorophyll- a and bottom water oxygen is less clear but may be important for some taxa. Biodiversity indices reveal strong west − east biogeographical differences among the basins that reflect the different histories of Mediterranean versus Ponto-Caspian connections. The atlas data provide a standardised taxonomy and regional database for interpreting downcore cyst variations in terms of quantitative oceanographic changes. The atlas also provides a baseline for monitoring further changes in the BSC dinocysts that may accompany the accelerating development of the region.

The influence of dissolved oxygen on dinoflagellate cyst distribution across Sluice Pond, a meromictic lake in NE Massachusetts, USA

ABSTRACTAssemblages of dinoflagellate cysts in lakebed sediments across the deep, meromictic basin of Sluice Pond (Lynn, Massachusetts) were compared with measurements of water quality and sediment geochemistry and with testate amoeba and tintinnid assemblages. Lakebed sediments below oxygenated waters (DO >2 mg/L) contain diverse testate amoebae, but sparse Peridinium willei-dominated dinoflagellate cyst assemblages. Sediments collected under hypoxic conditions (DO < 2 mg/L) showed higher preservation of organic carbon and nitrogen, and these deep basin sediments are characterised by diverse dinoflagellate cyst assemblages, but sieved microfossil assemblages are typically dominated by the planktonic Codonella cratera and the pseudo-planktonic Cucurbitella tricuspis. Strong inverse relationships of cysts of Peridinium willei (R2 = 0.81) and Difflugia oblonga tests (R2 = 0.7) with water depth are attributed to variations in bottom water oxygen concentrations. Both ecological and taphonomic factors must be considered when reconstructing palaeoenvironments from microfossil assemblages.

Do the levels of industrial pollutants influence the distribution and abundance of dinoflagellate cysts in the recently-deposited sediment of a Mediterranean coastal ecosystem?

We studied the relationships between sediment industrial pollutants concentrations, sediment characteristics and the dinoflagellate cyst abundance within a coastal lagoon by investigating a total of 55 sampling stations within the Bizerte lagoon, a highly anthropized Mediterranean ecosystem. The sediment of Bizerte lagoon is characterized by a high dinocyst abundance, reaching a maximum value of 2742cysts·g−1 of dry sediment. The investigated cyst diversity was characterized by the presence of 22 dominant dinocyst morphotypes belonging to 11 genera. Two dinoflagellate species dominated the assemblage: Alexandrium pseudogonyaulax and Protoperidinium claudicans, representing 29 to 89% and 5 to 38% of the total cyst abundance, respectively, depending on the station. Seven morphotypes belonging to potentially toxic species were detected, including Alexandrium minutum, A. pseudogonyaulax, Alexandrium catenella/tamarense species complex, Lingulodinium polyedrum, Gonyaulax cf. spinifera complex, Prorocentrum micans and Protoceratium reticulatum. Pearson correlation values showed a positive correlation (α=0.05) between cyst abundance and both water content and fine silt sediment content. Clustering revealed that the highest abundance of cysts corresponds to stations presenting the higher amounts of heavy metals. The simultaneous autoregressive model (SAM) highlighted a significant correlation (α=0.05) between cyst accumulation and two main factors: sediment water content and sediment content for several heavy metals, including Hg, Cd, Cu, Ni and Cr. These results suggest that the degree of heavy metal pollution could influence cyst accumulation patterns.

Dinoflagellate cyst distribution in sediments of western Bay of Bengal: Role of sea surface conditions

Bay of Bengal is a shallow marine basin exposed to seasonal fluctuation in precipitation and run-off. Thus, salinity, temperature, nutrient and productivity vary along the latitudinal and onshore-offshore gradient in the Bay of Bengal. These parameters directly affect primary productivity, including that of dinoflagellate cysts. The spatial distribution of organic walled dinoflagellates cyst is studied in the 50 surface samples of eight transects from the western Bay of Bengal, to infer variation in the environmental conditions in the region. The cyst diversity consists of 40 taxa with an overall high dominance of protoperidinioid cysts over gonyalaucoides. Based on the study distinct onshore and offshore dinocyst assemblages are identified. The high productive coastal upwelling region is characterised by the dominance of gonyalaucoid dinocyst species Bitectatodinium spongium (Zonneveld 1997) Zonneveld and Jurkschat 1999 indicating its adaptability to the fluctuating salinity and high nutrient conditions. The outer shelf to middle slope regions of western Bay of Bengal is dominated by the protoperidinioid species. This is in contrast to the gonyalaucoid dinocyst assemblages of the outer shelf to middle slope regions in other oceans. Since protoperidinioids prefer high nutrient and reducing environmental conditions for growth and preservation, their presence suggest high nutrient availability due to the river discharge and low oxygen condition in the slope region in Bay of Bengal. Statistical analyses of the sea surface parameters and dinoflagellate cyst abundance data indicate that salinity and silicates as a major source of nutrient played a major role in the distribution of dinoflagellate cyst in the Bay of Bengal.

A model of dinoflagellate cyst distribution around the K/Pg boundary and its paleoenvironmental implications (Eastern Alps)

A model of dinoflagellate cyst distribution around the K/Pg boundary and its paleoenvironmental implications (Eastern Alps)

제주 해안주변해역 표층퇴적물 중 와편모조류 시스트 군집의 분포특성

제주 해안주변해역 표층퇴적물 중 와편모조류 시스트 군집의 분포특성

Driving factors of dinoflagellate cyst distribution in surface sediments of a Mediterranean lagoon with limited access to the sea

Seasonal distribution of dinoflagellate cysts were studied at five surface sediment study stations in Ghar El Melh Lagoon (GML) (Tunisia) in relation to physicochemical parameters and phytoplankton abundance in the water column. At least sixteen dinocyst types were identified, dominated mainly by Protoperidinium spp., Scrippsiella trochoidea complex, Lingulodinum machaerophorum, Alexandrium spp. and Gymnodinium spp., along with many round brown cysts. Cyst abundance ranged from 0 to 229g−1 dry sediment. No significant differences in cyst distribution were found among stations, though a significant variation was observed among seasons with cyst dominance in autumn. No significant variation was found between cyst abundance and the different abiotic factors monitored, neither in the water column (physicochemical parameters) nor in the sediment (% H2O). Low dinocyst abundance was consistent with the dominance of non-cyst-forming dinoflagellates in the GML water column.

Biogeography of dinoflagellate cysts in northwest Atlantic estuaries.

Few biogeographic studies of dinoflagellate cysts include the near‐shore estuarine environment. We determine the effect of estuary type, biogeography, and water quality on the spatial distribution of organic‐walled dinoflagellate cysts from the Northeast USA (Maine to Delaware) and Canada (Prince Edward Island). A total of 69 surface sediment samples were collected from 27 estuaries, from sites with surface salinities >20. Dinoflagellate cysts were examined microscopically and compared to environmental parameters using multivariate ordination techniques. The spatial distribution of cyst taxa reflects biogeographic provinces established by other marine organisms, with Cape Cod separating the northern Acadian Province from the southern Virginian Province. Species such as Lingulodinium machaerophorum and Polysphaeridinium zoharyi were found almost exclusively in the Virginian Province, while others such as Dubridinium spp. and Islandinium? cezare were more abundant in the Acadian Province. Tidal range, sea surface temperature (SST), and sea surface salinity (SSS) are statistically significant parameters influencing cyst assemblages. Samples from the same type of estuary cluster together in canonical correspondence analysis when the estuaries are within the same biogeographic province. The large geographic extent of this study, encompassing four main estuary types (riverine, lagoon, coastal embayment, and fjord), allowed us to determine that the type of estuary has an important influence on cyst assemblages. Due to greater seasonal variations in SSTs and SSSs in estuaries compared to the open ocean, cyst assemblages show distinct latitudinal trends. The estuarine context is important for understanding present‐day species distribution, the factors controlling them, and to better predict how they may change in the future.

Scrippsiella trochoidea cysts in recent sediments from Amur Bay, Sea of Japan: distribution and phylogeny

Abstract A study of vertical distribution of dinoflagellate cysts in recent sediments was conducted for the first time in the Far Eastern seas of Russia. Dinoflagellate cysts were studied in sediment cores retrieved from five stations in Amur Bay (Peter the Great Bay, Sea of Japan) in 2010 and 2013. The Scrippsiella trochoidea complex was the dominant type of cyst, the average proportion of which (in the entire sediment cores) reached 39% of the total cyst abundance. The maximum abundance of S. trochoidea complex reached 5513 cysts g-1 dry sediment. Cysts of the S. trochoidea complex were found to remain viable in the sediments after exposure to sub-zero temperatures. The identification of S. trochoidea in the Far Eastern seas of Russia was first confirmed by using biomolecular genetic analyses. The study of vertical distribution showed that cysts of this species dominate the upper sediment layers (0–10 cm). A tendency for abundance to increase from the shore toward the middle part of the bay was observed in the spatial distribution of cysts.

Dinoflagellate cyst distribution in the oligotrophic environments of the Gulf of Aqaba and northern Red Sea

Abstract Oligotrophic environmental systems form a major part of the marine aquatic environments on earth. Compared to mesotrophic and eutrophic environments extremely little information is available about the relationship between the distribution of organic-walled dinoflagellate cysts and physical and biological gradients in the upper water column. Here we present the first comprehensive study of the modern geographic distribution of organic-walled dinoflagellate cysts in the oligotrophic environments of the northern Red Sea and Gulf of Aqaba. We show that sediments of both regions have characteristic dinoflagellate cyst associations consisting of both heterotrophic and phototrophic species of which the latter, including both autotrophic and mixotrophic species, form the major part of the associations in both regions. The upper water environment of the Gulf of Aqaba is characterized by slightly enhanced nutrient concentrations compared to the Red Sea, due to water column mixing in winter. Its phytoplankton composition is dominated by pico- and ultra-plankton and a slight higher amount of eukaryotes compared to northern Red Sea. Its sedimentary cyst associations are characterized by higher relative and absolute abundances of the species Brigantedinium spp., Votadinium calvum, Echinidinium spp., Lingulodinium machaerophorum, Spiniferites spp., Spiniferites bentorii, Spiniferites membranaceus and Spiniferites mirabilis. Sediments of the northern Red Sea are characterized by high relative abundances of Impagidinium aculeatum, Impagidinium sphaericum, Operculodinium israelianum, Operculodinium longispinigerum, Operculodinium centrocarpum, cysts of Pentapharsodinium dalei, and Selenopemphix nephroides. A positive relationship between the distribution of the heterotrophic species Brigantedinium spp., Echinidinium spp. and V. calvum with the occurrence of other eukaryotic groups such as e.g. diatoms is documented. The distribution of S. nephroides cannot be related to the presence of diatom occurrences and it is suggested that the distribution of food sources other than diatoms affects its distribution. We document a positive relationship between the sedimentary distribution of the phototrophic dinoflagellate species L. machaerophorum and Spiniferites species and the abundance of the cyanobacteria Synechococcus in the water column. Since Synechococcus is known to be a potential prey of Lingulodinium polyedrum and members of the Gonyaulax spinifera complex (the motile forms producing these cysts) we suggest a possible cyst distribution–prey relationship of mixotrophic dinoflagellates.

九龙江西陂库区沉积物甲藻孢囊的分布

PDF HTML阅读 XML下载 导出引用 引用提醒 九龙江西陂库区沉积物甲藻孢囊的分布 DOI: 10.5846/stxb201408041554 作者: 作者单位: 福建师范大学环境科学与工程学院,福建师范大学环境科学与工程学院,福建师范大学环境科学与工程学院,福建师范大学环境科学与工程学院,国家海洋局第三海洋研究所;国家海洋局第三海洋研究所 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目(41101060);福建省自然科学基金项目(2014J01154) Research on the distribution of dinoflagellate cysts in the surface sediments of the XiPi Reservoir in the Jiulong River Author: Affiliation: Environmental Science and Engineering College of Fujian Normal University Key Laboratory of Polymer Materials of Fujian Province,,,, Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:孢囊在甲藻的生活史中发挥重要作用,福建省九龙江从2009年起,暴发多次拟多甲藻水华事件。采用显微镜观察和单细胞PCR技术,对九龙江西陂库区2012-2013年不同月份沉积物中的甲藻孢囊进行种属判定,并对甲藻孢囊的分布及其影响因素进行分析。结果表明,西陂库区沉积物中的甲藻孢囊主要为拟多甲藻属,约占80%,其次为裸甲藻属,发现了2009年水华的优势种佩式拟多甲藻(Peridiniopsis penardii)孢囊。库区沉积物中甲藻孢囊的丰度在(13.7±1.2)-(105.2±8.3)个/g干重之间。多元相关分析结果显示甲藻孢囊的丰度与含水率呈现显著正相关性(P < 0.05),反映了甲藻孢囊沿水流方向逐渐积累。本研究结果填补了国内水库甲藻孢囊鉴定和萌发的研究空白,为九龙江甲藻水华的防治提供科学参考。 Abstract:Resting cysts play a major role in the life history of dinoflagellates. Peridiniopsis blooms have occurred many times in the Jiulongjiang River (Fujian province) since February 2009. This study investigates the characteristics of dinoflagellate cysts found in the sediments of the Xipi Reservoir in the Jiulongjiang River during different months, from 2012 to 2013. We used microscopy and single-cell Polymerase Chain Reaction (PCR) technology to identify the species of dinoflagellate cysts in a germination experiment. The results show that Peridiniopsis forms the dominant genus among the dinoflagellate cysts found in these sediments, and accounts for 80% of the total population while the rest belong to the genus Gymnodinium. We identified the cysts of Peridiniopsis penardii, the dominant bloom species in 2009. We also assessed the distribution and abundance of dinoflagellate cysts and investigated the driving factors of these population characteristics. The abundances of dinoflagellate cysts in sediments during different months are between (13.7 ± 1.2) to (105.2 ± 8.3) cysts/g DW. The multiple correlation analysis demonstrated that the abundance of dinoflagellate cysts is significantly positively correlated with moisture (P < 0.05). It showed that the distribution of dinoflagellate cysts gradually increased along the direction of the river flow. These results provide new insight into freshwater dinoflagellate cyst characterization and germination in this reservoir, and provide a scientific background for efforts aimed at the prevention of dinoflagellate blooms in the Jiulongjiang River. 参考文献 相似文献 引证文献

Calcareous dinoflagellate cysts and the Turonian nutrient crisis – Data from the upper Turonian of the Lower Saxony Basin (northern Germany)

Little information exists on the distribution of calcareous dinoflagellate cysts from the Turonian (Upper Cretaceous) of Germany, and the first taxonomic assessment of late Turonian calcareous dinoflagellate cysts from the Salder Formation (NW Germany, Lower Saxony Basin) is a first step to close this gap. Ca. 11.000 calcareous dinoflagellate cysts were considered for this study, representing seven taxa only. The dominant taxon is Pithonella, mainly represented by Pithonella sphaerica and Pithonella ovalis, while Pithonella cardiiformis and Pithonella discoidea are rare. The species Pithonella spiralis n. sp. is newly described. Non-pithonellid c-dinocysts are represented by Normandia circumperforata and Pirumella sp. The late Turonian c-dinocyst diversity of the NW German shelf sea is extremely low compared with the Early Cretaceous species richness in the same area. The diversity drop is explained to result from a Turonian nutrient crisis, caused by the drowning of source areas of nutrient input during the early Late Cretaceous sea-level highstand.

Middle-late Eocene dinoflagellate cysts from NE Ukraine (Borehole No. 230, Dnepr-Donets Depression): stratigraphic and palaeoenvironmental approach

Abstract Analysis of the stratigraphic and quantitative distribution of dinoflagellate cysts and other palynomorphs from a shallow marine Eocene section drilled from borehole No. 230 (NE Ukraine) resulted in an updated age-assessment of regional formations and a reconstruction of the major transgressive-regressive trends in the North Ukrainian palaeosedimentological province. Based on dinocyst age-diagnostic events, the Buchak Formation is attributed to the mid-upper Lutetian; the Kiev Formation is assigned to the Bartonian-?lowermost Priabonian; finally, the Obukhov Formation is dated Priabonian. The Buchak Formation accumulation reflects the first major transgressive episode in the North Ukrainian Province; the accumulation of the lower Kiev Formation corresponds to the maximum of regional marine transgression, while the palynological assemblages from the upper Kiev Formation indicate a protracted regression. The beginning of the Obukhov Formation accumulation corresponds to the last marine transgressive cycle.

Impact of industrial pollution on recent dinoflagellate cysts in Izmir Bay (Eastern Aegean)

The spatial distribution of dinoflagellate cysts was studied to understand the impact of industrial pollution on the surface sediment of Izmir Bay, Turkey. Forty two dinoflagellate cyst morphotypes belonging to 12 genera were identified and qualified at 12 sampling points. The cyst of Gymnodinium nolleri dominated the bay and had the highest abundance in most of the stations, following Spiniferites bulloideus and Lingulodinium machaerophorum. The highest cyst concentration was recorded in the inner part of the bay. Cyst concentration ranged between 384 and 9944cystg−1 dry weight of sediment in the sampling area. Sediment metal concentrations were determined. Heavy metal levels in Izmir Inner Bay were higher than the Middle and Outer Bay. L. machaerophorum, Dubridinium caperatum and Polykrikos kofoidii showed significant positive correlation with some metals (Cd, Pb, Cu, Zn) and organic carbon content. However, there was no significant correlation between dinoflagellate cyst abundance and sediment type.

Dinoflagellate Cyst Distribution during the Middle Eocene in the Drake Passage Area: Paleoceanographic Implications

The middle—late Eocene (45–36 Ma) dinoflagellate cyst distribution in high latitudes of the Southern Hemisphere has been explained by a surface ocean circulation pattern characterized by extensive subpolar gyres around Antarctica. Based on global paleoclimate models it has been proposed that these surface ocean gyres might favored the development of an Antarctic—endemic dinoflagellate cyst assemblage, which was consistently abundant until the end of the Eocene. During the late Eocene the deepening of the Tasman Gateway and the Drake Passage would have generated a circumpolar water flow responsible for the disruption of the local gyre system and the subsequent extinction of the endemic assemblage. Some authors have recently suggested that during the middle Eocene shallow water flows had already developed through incipient openings of the Tasman Gateway and the Drake Passage. In this review we have compared the middle Eocene dinoflagellate cysts assemblages dominated by the Antarctic—endemic species from localities of the Drake Passage area and performed a multivariate analysis to evaluate this hypothesis. Our results point out a clear differentiation between localities to the north and south of what now is the Drake Passage. While localities from the Antarctic Peninsula and Scotia Sea would had been affected by Antarctic surface waters, the Austral Basin would had been flooded by Antarctic waters together with Pacific waterflows developed through an incipient Drake Passage during the middle Eocene.

Surface sediment dinoflagellate cysts from the Hudson Bay system and their relation to freshwater and nutrient cycling

Abstract Surface sediment samples from the Hudson Bay system were analysed in order to examine the role of key regulators of arctic marine productivity — light and nutrients as affected by freshwater stratification and sea-ice cover — on the spatial distribution and production of dinoflagellate cysts. Total cyst fluxes vary from 0.2 × 10 6 to 30.6 × 10 6 cysts m − 2 a − 1 , with the highest values observed in eastern Hudson Bay. A total of 24 cyst taxa, representing 11 genera of five orders, were identified and distribution maps of the most common taxa have been produced. This is the first record of Echinidinium aculeatum , Echinidinium karaense , cf. Echinidinium delicatum , Islandinium brevispinosum , Selenopemphix quanta , cysts of Protoperidinium americanum , cysts of cf. Biecheleria sp. and Polarella glacialis in the Hudson Bay system. Dinoflagellate cyst assemblages show distinct spatial patterns revealing three compositional domains: eastern Hudson Bay, western-central Hudson Bay and Hudson Strait. The eastern domain is characterised by a dominance of autotrophic cysts of Pentapharsodinium dalei whereas the western-central domain is characterised by autotrophic Operculodinium centrocarpum with some contribution by heterotrophic Polykrikos sp. var. arctic morphotype and Polykrikos spp. Sites from Hudson Strait are distinguished by an overwhelming prevalence of heterotrophic Protoperidiniaceae cysts, mainly Islandinium minutum , and have the highest values of sedimentary biogenic silica, used as a proxy for diatom productivity. Sediment geochemical tracers are used as proxies for freshwater inputs (lignin and its biomarkers) and nitrate availability (nitrogen isotopes), and sea-ice concentrations derived from passive microwave data as a proxy for light availability. Sea-ice regulated length of the dark season has a negligible influence on the proportion and production of heterotrophic (dark-adapted) versus autotrophic (light-dependent) dinoflagellate cysts, perhaps due to the location of our study area on the southern fringe of the Arctic. Instead, cyst populations in Hudson Bay are primarily regulated by vertical stratification and nitrate availability, while in Hudson Strait the pivotal mechanism constitutes food availability.

Dinoflagellate cyst distribution in recent sediments along the south-east coast of India

The spatial variation in the dinoflagellate cyst assemblage from the south-east coast of India is presented along with a comparison of the cyst abundance from other regions of the world. Samples from 8 stations revealed the presence of 24 species from the genera Protoperidinium, Zygabikodinium, Gonyaulax, Lingulodinium and Gyrodinium. Cyst abundance was comparatively high at northern stations and was well correlated with the fine-grained (silt-clay dominated) sediments. In contrast, low cyst abundance was recorded in sandy sediments at southern stations. Fourteen cyst-forming dinoflagellate species previously unrecorded in planktonic samples were detected in the sediments. The cyst abundance recorded here is low (29–331 cysts g−1 dry sediment) as compared to sub-tropical and temperate regions, but it is on a par with tropical regions, including the west coast of India. Comparison of the cyst assemblage along the Indian coast revealed a smaller number of potentially harmful and red-tide-forming dinoflagellate species on the south-east coast (6 species) than on the west coast (10 species). Calcareous cysts of the genus Scrippsiella reported from the west coast and Visakhapatnam harbour (south-east coast) were not observed in this study although their planktonic cells have been reported.

Provenance of surface sediments along the southeastern Adriatic coast off Italy: An overview

Multi-proxy studies are necessary to understand sediment composition and related provenance on continental shelfs. Here it is shown that the spatial distribution of geochemical composition and grain size for surface sediments along the southeastern Italian coast is related to provenance and mechanisms influencing sediment pathways. A northern Adriatic/Italian provenance can be distinguished from a southern Apennine river source. This is done independent of grain size using the element ratios Ce/Ni and Zr/Cr. Furthermore, the origin of organic matter is determined using bulk carbon isotopes and the C/N ratio. Integrating these results with those from complementary studies on δ18O and δ13C of Globigerinoides ruber (white), the BIT index, stable isotopes of plant waxes and dinoflagellate cyst distribution from the same set of samples reveals that:•Sediments from the northwestern Adriatic are transported as far southward as the Gallipoli shelf (eastern Gulf of Taranto) by the Western Adriatic Current (WAC)•Along the WAC, there is a consistent southward decrease in Po river/northern Apennines provenance and a concomitant decrease in terrestrial (soil) organic matter (OM), whereas the percentage of marine OM increases.•The provenance for Gallipoli shelf sediments is for ∼80% attributed to Po River/northern Apennines sources and for ∼20% to southern Italian sources.•OM in the eastern Gulf of Taranto contains more marine OM than other areas within the WAC, whereas OM and sediments from the western part of the Gulf of Taranto have a more local, riverine provenance.

Distribution of dinoflagellate cysts in Yellow Sea sediments

To investigate the distribution, abundance, and species composition of dinoflagellate cysts in the Yellow Sea, surface sediment samples were collected at 37 sites, including the Korean dump site. Twenty-one dinoflagellate cyst taxa were identified, with the assemblages dominated mainly by Spiniferites bulloideus, Operculodinium centrocarpum, and cyst of Alexandrium catenella/tamarense type. A high frequency of O. centrocarpum in the Yellow Sea was observed for the first time, and it is likely that this can be attributed to the dynamics of the Yellow Sea Cold Water Mass and the Changjiang (Yangtze) River runoff. Total cyst concentrations ranged from 23 to 48 442 cysts/g dry weight, and high cyst concentrations were recorded adjacent to the dumping site. This result suggests that anthropogenic activities such as ocean dumping stimulate the growth of dinoflagellates in the Yellow Sea, which in turn leads to high levels of dinoflagellate cyst production.