Particulate and phytoplankton absorption during POLARSTERN cruises ANT-XXVI/3 and ANT-XXVIII/3

The euphotic depth (Zeu) is a key parameter in modelling primary production (PP) using satellite ocean colour. However, evaluations of satellite Zeu products are scarce. The objective of this paper is to investigate existing approaches and sensors to estimate Zeu from satellite and to evaluate how different Zeu products might affect the estimation of PP in the Southern Ocean (SO). Euphotic depth was derived from MODIS and SeaWiFS products of (i) surface chlorophyll-a (Zeu-Chla) and (ii) inherent optical properties (Zeu-IOP). They were compared with in situ measurements of Zeu from different regions of the SO. Both approaches and sensors are robust to retrieve Zeu, although the best results were obtained using the IOP approach and SeaWiFS data, with an average percentage of error (E) of 25.43% and mean absolute error (MAE) of 0.10 m (log scale). Nevertheless, differences in the spatial distribution of Zeu-Chla and Zeu-IOP for both sensors were found as large as 30% over specific regions. These differences were also observed in PP. On average, PP based on Zeu-Chla was 8% higher than PP based on Zeu-IOP, but it was up to 30% higher south of 60°S. Satellite phytoplankton absorption coefficients (aph) derived by the Quasi-Analytical Algorithm at different wavelengths were also validated and the results showed that MODIS aph are generally more robust than SeaWiFS. Thus, MODIS aph should be preferred in PP models based on aph in the SO. Further, we reinforce the importance of investigating the spatial differences between satellite products, which might not be detected by the validation with in situ measurements due to the insufficient amount and uneven distribution of the data.

Identificación de la brecha existente entre la ALFIN de los ingresantes y las competencias informacionales requeridas por la FHyCS-UNaM [ponencia]. En: VI Encuentro Iberoamericano de Colectivos Escolares y Redes de Maestras y Maestros que hacen investigación e innovación desde la escuela.

Los docentes de los primeros años de las distintas carreras que se dictan en la Facultad de Humanidades y Ciencias Sociales de la Universidad Nacional de Misiones (en adelante FHyCS-UNaM) coinciden en afirmar que los alumnos “ingresantes” demuestran un importante déficit de alfabetización informacional (en adelante ALFIN). Con el fin de verificar estos supuestos e identificar los puntos sobresalientes de la brecha informacional, que se advierte como existente frente a los requerimientos iniciales para acceder a la institución, se diseñó un proyecto de investigación, de tipo exploratorio, que aportara elementos teóricos, conceptuales y esquemas de acción que faciliten, a través de las TIC, la accesibilidad y permanencia del alumnado que ingresa a la comunidad universitaria. Este proyecto se inició en el año 2008 y continúa. En este trabajo se presenta el análisis de algunos de los resultados que permitieron arrojar luz sobre el problema.

Bacterial production in the eastern Mediteranean Sea in October 2008 during SES_GR2

The HCMR_SES_LAGRANGIAN_GR2_ MICROBIAL PARAMETERS dataset is based on samples collected in the framework of the project SESAME, in the North Aegean Sea during October 2008. The objectives were to measure the standing stocks and calculate the production of the microbial compartment of the food web, describe the vertical distribution pattern and characterize its structure and function through the water column as influenced by the BSW. Bacterial production was estimated by the 3H-leucine method (Kirchman et al. 1986, Kirchman 1993). At each depth, duplicate samples and a control were incubated with 20 nM L-[4,5 3H]-leucine. Samples were incubated in the dark, at in situ temperature.