2026-04-13T13:30:28Zhttps://recercat.cat/oai/requestoai:recercat.cat:10256/136532024-10-29T08:21:58Zcom_2072_452992com_2072_2054col_2072_453154
RECERCAT
author
Di Donato, Valentino
author
Martín Fernández, Josep Antoni
author
Daunis-i-Estadella, Pepus
author
Esposito, Paola
2024-10-29T08:21:58Z
2024-10-29T08:21:58Z
2011-05-13
http://hdl.handle.net/10256/13653
The choice of the sediment size fraction in the analysis of fossil planktonic foraminifera is of
great importance in determining the composition of assemblages. In past studies several size
fractions have been utilised. Imbrie and Kipp (1971) stated that “smaller fractions give rise to too
many uncertainties in the identification of small specimens and require too long to process. Large
mesh size yield undesiderable loss of small species, and small specimens of larger species”. The
adoption of coarser sieve meshes has the effect to reduce the percentages of small sized (usually
living in cold waters) species (Bé and Hutson, 1977). In a comparison between >63 μm and >150
μm size-fraction of planktonic foraminifera assemblages from NW Atlantic Ocean, Smart (2002),
stated that because particular smaller species are either under-represented or even absent from the
larger (>150 μm) size-fraction, the smaller (>63 μm) size-fraction must be included in studies of
planktonic foraminifera. Di Donato et al. (2008) highlighted in the >150 μm size fraction of a core
from the Tyrrhenian Sea, a great loss of the small-sized species Turborotalita quinqueloba in glacial
samples, where this species is very abundant. This caused an increase in warm water species such as
Globigerinoides ruber, apparently reaching typical Holocene values in some full glacial levels.
From the above mentioned statements, it is clear that treatment changes can strongly influence the
results of palaeoclimatic reconstructions based on planktonic foraminiferal assemblages.
As stated by Aitchison (1986, 1992) scale invariance and subcompositional coherence are
fundamental properties of the compositional data analysis (CODA). The main goal of this paper is
to verify if the variable relationships pointing out from CODA of foraminiferal assemblages are or
not influenced by the size fraction and, more in general, to test the robustness of CODA respect to
treatment changes related to different preparation techniques for the analysis of planktonic foraminifera
info:eu-repo/semantics/openAccess
Estadística matemàtica -- Congressos
Mathematical statistics -- Congresses
Anàlisi multivariable -- Congressos
Mathematical statistics -- Congresses
Foraminífers fòssils -- Mètodes estadístics -- Congressos
Foraminifera, Fossil -- Statistical methods -- Congresses
Analysis of Fossil Planktonic Foraminifera: The Sieve Mesh Effect
info:eu-repo/semantics/bookPart info:eu-repo/semantics/publishedVersion