GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Potential and limitations of applying the mean temperature approach to fossil otolith assemblages
    Springer Science and Business Media LLC ; 2022
    In:  Environmental Biology of Fishes Vol. 105, No. 10 ( 2022-10), p. 1269-1286
    Details
    In: Environmental Biology of Fishes, Springer Science and Business Media LLC, Vol. 105, No. 10 ( 2022-10), p. 1269-1286
    Abstract: Evaluation of the impact of climatic changes on the composition of fish assemblages requires quantitative measures that can be compared across space and time. In this respect, the mean temperature of the catch (MTC) approach has been proven to be a very useful tool for monitoring the effect of climate change on fisheries catch. Lack of baseline data and deep-time analogues, however, prevent a more comprehensive evaluation. In this study, we explore the applicability of the mean temperature approach to fossil fish faunas by using otolith assemblage data from the eastern Mediterranean and the northern Adriatic coastal environments corresponding to the last 8000 years (Holocene) and the interval 2.58–1.80 Ma B. P. (Early Pleistocene). The calculated mean temperatures of the otolith assemblage (MTO) range from 13.5 to 17.3 °C. This case study shows that the MTO can successfully capture compositional shifts in marine fish faunas based on variations in their climatic affinity driven by regional climate differences. However, the index is sensitive to methodological choices and thus requires standardized sampling. Even though theoretical and methodological issues prevent direct comparisons between MTO and MTC values, the MTO offers a useful quantitative proxy for reconstructing spatial and temporal trends in the biogeographic affinity of fossil otolith assemblages.
    Type of Medium: Online Resource
    ISSN: 0378-1909 , 1573-5133
    URL: Article
    DOI: 10.1007/s10641-022-01252-6
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2022
    detail.hit.zdb_id: 196790-3
    detail.hit.zdb_id: 1497685-7
    SSG: 21,3
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Millennial-scale changes in abundance of brachiopods in bathyal environments detected by postmortem age distributions in death assemblage (Bari Canyon, Adriatic Sea)
    Geological Society of London ; 2023
    In:  Geological Society, London, Special Publications Vol. 529, No. 1 ( 2023-07-03), p. 153-174
    Details
    In: Geological Society, London, Special Publications, Geological Society of London, Vol. 529, No. 1 ( 2023-07-03), p. 153-174
    Abstract: Inferring the composition of pre-Anthropocene baseline communities on the basis of death assemblages (DAs) preserved in a surface mixed layer requires discriminating among recently-dead shells sourced by living populations and older shells from extirpated populations. Here, we assess the distribution of postmortem ages in the DA formed by the brachiopod Gryphus vitreus at 580 m depth in the Bari Canyon (Adriatic Sea), with no individuals collected alive. The Gryphus DA exhibits millennial time averaging (inter-quartile range = 1250 years) and two modes in abundance at 500 and 1750 years BP. As high abundance of species in time-averaged DAs can reflect passive accumulation of shells sourced by populations with low standing population density, we reconstruct changes in annual density on the basis of the abundance maxima detected in the distribution of postmortem ages and on the basis of estimates of per-specimen disintegration rate. We find that adults ( 〉 20 mm) achieved densities of at least 10–20 individuals/m 2 (assuming lifespan is 10 years), and the pulses in abundance were thus associated with a high population density in the past, followed by the decline over the last few centuries. We infer that bathyal populations were volatile during the Late Holocene, with brachiopods sensitive to siltation that was induced by temporal changes in sediment dispersal into the Bari Canyon due to deforestation and climatic changes.
    Type of Medium: Online Resource
    ISSN: 0305-8719 , 2041-4927
    URL: Article
    DOI: 10.1144/SP529-2022-117
    Language: English
    Publisher: Geological Society of London
    Publication Date: 2023
    detail.hit.zdb_id: 2478172-1
    detail.hit.zdb_id: 196249-8
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Quantitative comparison of Pleistocene and Recent coral reef habitats in the northern Red Sea (El Quseir, Egypt)
    Springer Science and Business Media LLC ; 2016
    In:  Facies Vol. 62, No. 2 ( 2016-4)
    Details
    In: Facies, Springer Science and Business Media LLC, Vol. 62, No. 2 ( 2016-4)
    Type of Medium: Online Resource
    ISSN: 0172-9179 , 1612-4820
    URL: Article
    DOI: 10.1007/s10347-016-0468-6
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2016
    detail.hit.zdb_id: 2045898-8
    SSG: 13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Molluscan benthic communities at Brijuni Islands (northern Adriatic Sea) shaped by Holocene sea-level rise and recent human eutrophication and pollution
    SAGE Publications ; 2018
    In:  The Holocene Vol. 28, No. 11 ( 2018-11), p. 1801-1817
    Details
    In: The Holocene, SAGE Publications, Vol. 28, No. 11 ( 2018-11), p. 1801-1817
    Abstract: The effects of and the interplay between natural and anthropogenic influences on the composition of benthic communities over long time spans are poorly understood. Based on a 160-cm-long sediment core collected at 44 m water depth in the NE Adriatic Sea (Brijuni Islands, Croatia), we document changes in molluscan communities since the Holocene transgression ~11,000 years ago and assess how they were shaped by environmental changes. We find that (1) a transgressive lag deposit with a mixture of terrestrial and marine species contains abundant seagrass-associated gastropods and epifaunal suspension-feeding bivalves, (2) the maximum-flooding phase captures the establishment of epifaunal bivalve-dominated biostromes in the photic zone, and (3) the highstand phase is characterized by increasing infaunal suspension feeders and declining seagrass-dwellers in bryozoan-molluscan muddy sands. Changes in the community composition between the transgressive and the highstand phase can be explained by rising sea level, reduced light penetration, and increase in turbidity, as documented by the gradual up-core shift from coarse molluscan skeletal gravel with seagrass-associated molluscs to bryozoan sandy muds. In the uppermost 20 cm (median age 〈 200 years), however, epifaunal and grazing species decline and deposit-feeding and chemosymbiotic species increase in abundance. These changes concur with rising concentrations of nitrogen and organic pollutants due to the impact of eutrophication, pollution, and trawling in the 20th century. The late highstand benthic assemblages with abundant bryozoans, high molluscan diversity, and abundance of soft-bottom epi- and infaunal filter feeders and herbivores represent the circalittoral baseline community largely unaffected by anthropogenic impacts.
    Type of Medium: Online Resource
    ISSN: 0959-6836 , 1477-0911
    URL: Article
    DOI: 10.1177/0959683618788651
    RVK:
    RA 1000
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2018
    detail.hit.zdb_id: 2027956-5
    SSG: 14
    SSG: 3,4
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Radiocarbon dating supports bivalve-fish age coupling along a bathymetric gradient in high-resolution paleoenvironmental studies
    Geological Society of America ; 2020
    In:  Geology Vol. 48, No. 6 ( 2020-06-01), p. 589-593
    Details
    In: Geology, Geological Society of America, Vol. 48, No. 6 ( 2020-06-01), p. 589-593
    Abstract: Studies of paleocommunities and trophic webs assume that multispecies assemblages consist of species that coexisted in the same habitat over the duration of time averaging. However, even species with similar durability can differ in age within a single fossil assemblage. Here, we tested whether skeletal remains of different phyla and trophic guilds, the most abundant infaunal bivalve shells and nektobenthic fish otoliths, differed in radiocarbon age in surficial sediments along a depth gradient from 10 to 40 m on the warm-temperate Israeli shelf, and we modeled their dynamics of taphonomic loss. We found that, in spite of the higher potential of fishes for out-of-habitat transport after death, differences in age structure within depths were smaller by almost an order of magnitude than differences between depths. Shell and otolith assemblages underwent depth-specific burial pathways independent of taxon identity, generating death assemblages with comparable time averaging, and supporting the assumption of temporal and spatial co-occurrence of mollusks and fishes.
    Type of Medium: Online Resource
    ISSN: 0091-7613 , 1943-2682
    URL: Article
    URL: Article
    DOI: 10.1130/G47210.1
    DOI: 10.1130/2020173
    Language: English
    Publisher: Geological Society of America
    Publication Date: 2020
    detail.hit.zdb_id: 184929-3
    detail.hit.zdb_id: 2041152-2
    SSG: 13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    Multiple phyla, one time resolution? Similar time averaging in benthic foraminifera, mollusk, echinoid, crustacean, and otolith fossil assemblages
    Geological Society of America ; 2022
    In:  Geology Vol. 50, No. 8 ( 2022-08-01), p. 902-906
    Details
    In: Geology, Geological Society of America, Vol. 50, No. 8 ( 2022-08-01), p. 902-906
    Abstract: Time averaging of fossil assemblages determines temporal precision of paleoecological and geochronological inferences. Taxonomic differences in intrinsic skeletal durability are expected to produce temporal mismatch between co-occurring species, but the importance of this effect is difficult to assess due to lack of direct estimates of time averaging for many higher taxa. Moreover, burial below the taphonomic active zone and early diagenetic processes may alleviate taxonomic differences in disintegration rates in subsurface sediments. We compared time averaging across five phyla of major carbonate producers co-occurring in a sediment core from the northern Adriatic Sea shelf. We dated individual bivalve shells, foraminiferal tests, tests and isolated plates of irregular and regular echinoids, crab claws, and fish otoliths. In spite of different skeletal architecture, mineralogy, and life habit, all taxa showed very similar time averaging varying from ~1800 to ~3600 yr (interquartile age ranges). Thus, remains of echinoids and crustaceans—two groups with multi-elemental skeletons assumed to have low preservation potential—can still undergo extensive age mixing comparable to that of the co-occurring mollusk shells. The median ages of taxa differed by as much as ~3700 yr, reflecting species-specific timing of seafloor colonization during the Holocene transgression. Our results are congruent with sequestration models invoking taphonomic processes that minimize durability differences among taxa. These processes together with temporal variability in skeletal production can overrule the effects of durability in determining temporal resolution of multi-taxic fossil assemblages.
    Type of Medium: Online Resource
    ISSN: 0091-7613 , 1943-2682
    URL: Article
    DOI: 10.1130/G49970.1
    Language: English
    Publisher: Geological Society of America
    Publication Date: 2022
    detail.hit.zdb_id: 184929-3
    detail.hit.zdb_id: 2041152-2
    SSG: 13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    Anthropogenically induced environmental changes in the northeastern Adriatic Sea in the last 500 years (Panzano Bay, Gulf of Trieste)
    Copernicus GmbH ; 2016
    In:  Biogeosciences Vol. 13, No. 21 ( 2016-11-01), p. 5965-5981
    Details
    In: Biogeosciences, Copernicus GmbH, Vol. 13, No. 21 ( 2016-11-01), p. 5965-5981
    Abstract: Abstract. Shallow and sheltered marine embayments in urbanized areas are prone to the accumulation of pollutants, but little is known about the historical baselines of such marine ecosystems. Here we study foraminiferal assemblages, geochemical proxies and sedimentological data from 1.6 m long sediment cores to uncover  ∼  500 years of anthropogenic pressure from mining, port and industrial activities in the Gulf of Trieste, Italy. From 1600 to 1900 AD, normalized element concentrations and foraminiferal assemblages point to negligible effects of agricultural activities. The only significant anthropogenic activity during this period was mercury mining in the hinterlands of the gulf, releasing high amounts of mercury into the bay and significantly exceeding the standards on the effects of trace elements on benthic organisms. Nonetheless, the fluctuations in the concentrations of mercury do not correlate with changes in the composition and diversity of foraminiferal assemblages due to its non-bioavailability. Intensified agricultural and maricultural activities in the first half of the 20th century caused slight nutrient enrichment and a minor increase in foraminiferal diversity. Intensified port and industrial activities in the second half of 20th century increased the normalized trace element concentrations and persistent organic pollutants (PAH, PCB) in the topmost part of the core. This increase caused only minor changes in the foraminiferal community because foraminifera in Panzano Bay have a long history of adaptation to elevated trace element concentrations. Our study underlines the importance of using an integrated, multidisciplinary approach in reconstructing the history of environmental and anthropogenic changes in marine systems. Given the prolonged human impacts in coastal areas like the Gulf of Trieste, such long-term baseline data are crucial for interpreting the present state of marine ecosystems.
    Type of Medium: Online Resource
    ISSN: 1726-4189
    URL: Article
    URL: Article
    DOI: 10.5194/bg-13-5965-2016
    DOI: 10.5194/bg-13-5965-2016-supplement
    Language: English
    Publisher: Copernicus GmbH
    Publication Date: 2016
    detail.hit.zdb_id: 2158181-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    Inferring time averaging and hiatus durations in the stratigraphic record of high‐frequency depositional sequences
    Wiley ; 2022
    In:  Sedimentology Vol. 69, No. 3 ( 2022-04), p. 1083-1118
    Details
    In: Sedimentology, Wiley, Vol. 69, No. 3 ( 2022-04), p. 1083-1118
    Abstract: A sequence stratigraphic framework predicts that time averaging and hiatus durations will be long at times of fastest sea‐level rise. This prediction does not necessarily apply to environments where carbonate production keeps up with sea‐level rise and where undetected hiatuses decouple short‐term from long‐term sedimentation rates. The taphonomic clock, however, which measures the residence time of skeletal particles in the mixed layer, can estimate the duration of hiatuses if the rate of skeletal alteration is slow and if skeletal particles endure long‐term exposure in the mixed layer. Here, time averaging is calibrated by using evidence from alteration of bivalves in a metre‐scale Holocene sequence in the Adriatic Sea. In this sequence, transgressive molluscan lags, a maximum‐flooding zone shell bed with bivalves, and highstand bryomol assemblages were all deposited under similar long‐term sedimentation rates ( ca 0.01 to 0.03 cm year −1 ) and exhibit millennial time averaging. Median ages of valves stained by pyrite and cemented by high‐magnesium calcitic micritic envelopes exceeding ca 1000 years indicate that: (i) these authigenic processes are slow in subsurface zones with reducing conditions (with prolonged sulphate reduction and carbonate ions sourced from dissolved shells in the surface zones); and (ii) subsurface micrite precipitation prolongs the disintegration half‐lives of valves exhumed to surface zones from decades to millennia. The high abundance of stained valves, valves with micrite envelopes, and valves with composite alteration (encrusters and borers colonizing stained and cemented grains) thus identifies hiatuses and skeletal concentrations time‐averaged to 〉 1000 years. The upcore decrease in abundance of valves with composite alteration, coupled with temporally‐constant long‐term sedimentation rates and time averaging, indicates that a temporal decline in sediment exhumation was compensated by a decline in burial of skeletal carbonate produced by molluscs.
    Type of Medium: Online Resource
    ISSN: 0037-0746 , 1365-3091
    URL: Issue
    URL: Article
    DOI: 10.1111/sed.v69.3
    DOI: 10.1111/sed.12936
    RVK:
    RB 10121
    Language: English
    Publisher: Wiley
    Publication Date: 2022
    detail.hit.zdb_id: 2020955-1
    detail.hit.zdb_id: 206889-8
    SSG: 13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 9
    Online Resource
    Online Resource
    A decline in molluscan carbonate production driven by the loss of vegetated habitats encoded in the Holocene sedimentary record of the Gulf of Trieste
    Wiley ; 2019
    In:  Sedimentology Vol. 66, No. 3 ( 2019-04), p. 781-807
    Details
    In: Sedimentology, Wiley, Vol. 66, No. 3 ( 2019-04), p. 781-807
    Abstract: Carbonate sediments in non‐vegetated habitats on the north‐east Adriatic shelf are dominated by shells of molluscs. However, the rate of carbonate molluscan production prior to the 20th century eutrophication and overfishing on this and other shelves remains unknown because: (i) monitoring of ecosystems prior to the 20th century was scarce; and (ii) ecosystem history inferred from cores is masked by condensation and mixing. Here, based on geochronological dating of four bivalve species, carbonate production during the Holocene is assessed in the Gulf of Trieste, where algal and seagrass habitats underwent a major decline during the 20th century. Assemblages of sand‐dwelling Gouldia minima and opportunistic Corbula gibba are time‐averaged to 〉 1000 years and Corbula gibba shells are older by 〉 2000 years than shells of co‐occurring Gouldia minima . This age difference is driven by temporally disjunct production of two species coupled with decimetre‐scale mixing. Stratigraphic unmixing shows that Corbula gibba declined in abundance during the highstand phase and increased again during the 20th century. In contrast, one of the major contributors to carbonate sands – Gouldia minima – increased in abundance during the highstand phase, but declined to almost zero abundance over the past two centuries. Gouldia minima and herbivorous gastropods associated with macroalgae or seagrasses are abundant in the top‐core increments but are rarely alive. Although Gouldia minima is not limited to vegetated habitats, it is abundant in such habitats elsewhere in the Mediterranean Sea. This live–dead mismatch reflects the difference between highstand baseline communities (with soft‐bottom vegetated zones and hard‐bottom Arca beds) and present‐day oligophotic communities with organic‐loving species. Therefore, the decline in light penetration and the loss of vegetated habitats with high molluscan production traces back to the 19th century. More than 50% of the shells on the sea floor in the Gulf of Trieste reflect inactive production that was sourced by heterozoan carbonate factory in algal or seagrass habitats.
    Type of Medium: Online Resource
    ISSN: 0037-0746 , 1365-3091
    URL: Issue
    URL: Article
    DOI: 10.1111/sed.2019.66.issue-3
    DOI: 10.1111/sed.12516
    RVK:
    RB 10121
    Language: English
    Publisher: Wiley
    Publication Date: 2019
    detail.hit.zdb_id: 2020955-1
    detail.hit.zdb_id: 206889-8
    SSG: 13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 10
    Online Resource
    Online Resource
    High‐frequency cycles of brachiopod shell beds on subaqueous delta‐scale clinoforms (early Pliocene, south‐east Spain)
    Wiley ; 2019
    In:  Sedimentology Vol. 66, No. 5 ( 2019-08), p. 1486-1530
    Details
    In: Sedimentology, Wiley, Vol. 66, No. 5 ( 2019-08), p. 1486-1530
    Abstract: During the early Pliocene, subaqueous delta‐scale clinoforms developed in the Águilas Basin, in a mixed temperate carbonate–siliciclastic system. The facies distribution is consistent with the infralittoral prograding wedge model. Stacking patterns and bounding surfaces indicate that the clinoforms formed during the highstand and falling sea‐level stages of a high rank cycle. Twenty‐two prograding clinothems were recognized over a distance of ≥1 km. Biostratigraphic data indicate a time span shorter than 700 kyr for the whole unit ( MP l3 biozone of the Mediterranean Pliocene). Cyclic skeletal concentrations and occasional biostromes of suspension feeders (terebratulid brachiopods, modiolid bivalves and adeoniform bryozoan colonies), slightly evolved glauconite and occasional Glossifungites ichnofacies formed on the clinoforms during high‐frequency pulses of relative sea‐level rise. During such stages, increased accommodation space in the topsets of the clinoforms caused a strong reduction of terrigenous input into the foresets and bottomsets. This provided favourable conditions for the development of these suspension feeder palaeocommunities. During stillstand stages, however, reduced accommodation space in the topsets eventually resumed progradation in the foresets. There, the abundance of Ditrupa tubes indicates frequent siltation events that extirpated the terebratulid populations and other epifaunal suspension feeders in the foreset and bottomset subenvironments. The occurrence of shell beds on the clinoforms suggests that this case study represents lower progradation rates than standard examples where shell beds bound the clinobedded units at their base and top only. Importantly, the distributions of biofacies and ichnoassemblage associations contribute significantly to the understanding of the effects of relative sea‐level fluctuations on the evolution of subaqueous delta‐scale clinoform systems.
    Type of Medium: Online Resource
    ISSN: 0037-0746 , 1365-3091
    URL: Issue
    URL: Article
    DOI: 10.1111/sed.2019.66.issue-5
    DOI: 10.1111/sed.12541
    RVK:
    RB 10121
    Language: English
    Publisher: Wiley
    Publication Date: 2019
    detail.hit.zdb_id: 2020955-1
    detail.hit.zdb_id: 206889-8
    SSG: 13
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...