Note on the diameter of otolith nucleus as a characteristic of the population groups of anchovy, Engraulis encrasicolus (Linnaeus, 1758), of the Cantabrian Sea and Galicia

The diameters of the nuclei of anchovy, Engraulis encrasicolus (Linnaeus, 1758), otoliths collected in 1995 and 1998 in the eastern Cantabrian Sea, the western Cantabrian Sea and Galicia (northwest Spain) have been measured to check possible differences in their length and, if they existed, whether they were characteristic of a different growth rate of the population groups of this species. Significant differences among the three regions were found. Although our results must be considered only preliminary, they seem to indicate that such differences can be characteristics of the population groups described in the regions studied.Se ha medido el diámetro del núcleo de otolitos de anchoa, Engraulis encrasicolus (Linnaeus, 1758), recogidos en el Cantábrico oriental, en el occidental y en Galicia durante 1995 y 1998 para comprobar si existían diferencias en su longitud y, si era así, si estas diferencias eran características de los grupos de población de la especie. Los resultados muestran diferencias significativas entre las tres regiones y, aunque deben considerarse solamente como preliminares, parecen indicar que estas diferencias pueden ser propias de los grupos de población de anchoa descritos en las regiones estudiadas.Instituto Español de Oceanografí

Terrestrial impact structures as geoheritage: an assessment method of their scientific value and its application to Brazil

Terrestrial impact structures are geological and geomorphological features with particular importance to understand the history and evolution of the planet. Impact structures are scattered around the world but in many countries these features are under threat, essentially due to anthropic factors. Impact structures with higher scienti c value should be considered as geological heritage and, consequently, be subjected to geoconservation strategies. In order to select the most important impact structures to be properly conserved and managed, this paper proposes a quantitative assessment method of the scienti c value of these structures. The eight Brazilian impact structures were used to test this method that has the potential to be applied to any geological context in any country. The structures known as Araguainha Dome-MT and Serra da Cangalha-TO reached a higher scienti c value, which justi es the need to develop geoconservation strategies and a proper management.The Conselho Nacional de Pesquisa e Desenvolvimento (CNPq / National Council for Research and Development) and the Programa Ciências sem Fronteiras / Science Without Borders Programme are acknowledged for the support of the postdoctoral grant No 233209/2013-1 of the 1st author. The work was co-funded by the European Union through the European Regional Development Fund, based on COMPETE 2020 (Programa Operacional da Competitividade e Internacionalização), project ICT (UID/ GEO/04683/2013) with reference POCI-01-0145- FEDER-007690 and Portuguese funds provided by Fundação para a Ciência e Tecnologia.info:eu-repo/semantics/publishedVersio

Denudation and geomorphic change in the Anthropocene; a global overview

The effects of human activity on geomorphic processes, particularly those related to denudation/sedimentation, are investigated by reviewing case studies and global assessments covering the past few centuries. Evidence we have assembled from different parts of the world, as well as from the literature, show that certain geomorphic processes are experiencing an acceleration, especially since the mid-twentieth century. This suggests that a global geomorphic change is taking place, largely caused by anthropogenic landscape changes

¿Es el diámetro del núcleo del otolito una característica de los grupos de población de la anchoa, Engraulis encrasicolus (Linnaeus, 1758), del Cantábrico y Galicia?

Publicado

The diet of the horse mackerel, Trachurus trachurus (Linnaeus 1758), in the Cantabrian Sea (north of Spain)

Publicado

Linking photosynthesis and sun-induced fluorescence at sub-daily to seasonal scales

Due to its close link to the photosynthetic process, sun-induced chlorophyll fluorescence (F) opens new possibilities to study dynamics of photosynthetic light reactions and to quantify CO2 assimilation rates. Although recent studies show that F is linearly related to gross primary production (GPP) on coarse spatial and temporal scales, it is argued that this relationship may be mainly driven by seasonal changes in absorbed photochemical active radiation (APAR) and less by the plant light use efficiency (LUE).In this work a high-resolution spectrometer was used to continuously measure red and far-red fluorescence and different reflectance indices within a sugar beet field during the growing season in 2015. Diurnal and seasonal developments were compared to eddy covariance derived GPP.Additionally, part of the time series coincided with a heatwave. The induced drought stress allowed us to observe F and its relationship to GPP under changing environmental conditions during the seasonal cycle.Across the season a strong linear relationship between GPP and F760 was found. This relationship however, was mainly driven by changes in APAR and was strongly reduced under drought conditions. We could show that far-red fluorescence yield can explain 59% of the diurnal and 79% of the seasonal variance in the light use efficiency. However, an even stronger relationship between FY760 and the structural vegetation index MTVI2 was found, implying that FY760 is affected by seasonal structural changes of the canopy. Nevertheless, the seasonally de-trended FY760 and PRI show that they share strong interdependencies with seasonal and diurnal LUE, in particular under drought stress conditions