Paula Diz

Moodle's Workshop plugin is designed for individual assignments and does not adequately handle group submissions, often resulting in discrepancies in the grades assigned to members of the same group. In this study, we present an external, open-access Python tool that automatically extracts grading data from Moodle Workshop, identifies group membership, calculates submission grades for each group (the same for all team members), and exports final grades to the Moodle gradebook. We illustrate the approach through a case study with first-year Marine Science undergraduates at University of Vigo, where students completed a practical teamwork assignment involving the calculation of the calcium carbonate content of a sediment. Our analysis shows that the modified group grades slightly differ from the default Moodle grades. The proposed methodology enhances consistency and transparency in group-based peer assessment and provides a reproducible framework for similar teaching contexts.

The transition from 41-kyr to 100-kyr climate cycles during the Mid-Pleistocene Transition (MPT; 1250–700 kyr), occurred in the absence of any significant shift in orbital forcing. The increase of carbon storage in the deep ocean between Marine Isotope Stage (MIS) 24–22 has been suggested as a main internal factor leading to the transition to 100-kyr glacial cycles. We present sedimentary redox proxies and benthic foraminifera assemblages that demonstrate persistent dysoxic conditions during the MPT at IODP Site U1314 (subpolar North Atlantic). During glacials between 940 and 870 kyr, benthic foraminifera species typical of high porewater oxygen concentration disappeared, and concentrations of manganese oxides and reactive phosphorus mineral phases, both influenced by redox state, showed reductions exceeding 50%. Here, we show that higher freshwater supply associated with ice-rafted delivery caused a reduction in deep-water convection, decreasing bottom-water oxygenation and favoring carbon storage in the subpolar North Atlantic during the MPT.

Benthic foraminifera are important components of the ocean benthos and play a major role in ocean biogeochemistry and ecosystem functioning. Generating ecological baselines for ocean monitoring or biogeographical distributions requires a reference dataset of recent census data. Moreover, the information from their modern biogeography can be used to interpret past environmental changes on the seafloor. In this study, we provide the first comprehensive quantitative benthic foraminifera database from surface sediments of the eastern Pacific (BENFEP). Through the collation of archival quantitative data on species abundance and their homogenization according to the most recent taxonomic standards, we are able to provide a database with 3077 sediment samples, corresponding to 2509 georeferenced stations of wide geographical (60^∘ N–54^∘ S) and water depth (0–7280 m) coverage. The quantitative data include living, dead, and living plus dead assemblages obtained from 50 published and unpublished documents. As well as describing the data collection and subsequent harmonization steps, we provide summarized information on metadata, examples of species' distributions, potential applications of the database, and recommendations for data archiving and publication of benthic foraminiferal data. The database is enriched with meaningful metadata for accessible data management and exploration with R software and geographical information systems. The first version of the database (BENFEP_v1, Diz et al., 2022a, https://doi.org/10.1594/PANGAEA.947086) is provided in short and long format, and it will be upgraded with new entries and when changes are needed to accommodate taxonomic revisions.

The Middle Pleistocene Transition (MPT, ~641–920 ka) represents a period of the Quaternary climate when, in the absence of substantial changes in orbital forcing, the climate progressively shifted to the 100 ka asymmetrical glacial–interglacial cyclicity characterizing the current climate. The causes of this change remain still uncertain but several lines of evidence suggested the carbon storage of the deep ocean played a relevant role. Here we evaluate the contribution of the eastern deep tropical Pacific to the global ocean carbon sequestration and storage between 760 and 1,040 ka. We present multi‐proxy records for export production and the redox environment at the seabed from Ocean Drilling Program Site 1242 located in the deep East Equatorial Pacific. Our data indicate the development of suboxic bottom waters during early marine isotopic stage (MIS) 23 and glacial MIS 22, suggesting the capture and storage of respired carbon. Redox‐sensitive elements suggest the progressive oxygenation of the deep ocean initiated at the end of the glacial MIS 22, continued across deglaciation and ended with the accomplishment of full interglacial MIS 21. We describe this pattern as a “less complete deglacial ventilation” in that it differs from the mid‐late Pleistocene Pacific deep ocean ventilation pattern which occurs during deglaciations. The ventilation of the deep Pacific Ocean extending beyond deglaciation might have contributed to a persistent deep ocean carbon sequestration, which might have resulted in lowered atmospheric CO₂ values that could have influenced the internal response of the climate system contributing to the development of the 100 ka climate variability.