Manganese accumulation and its relation to "eucalyptus shoot blight in the Vale do Rio Doce"

Eucalyptus Shoot Blight in the Vale do Rio Doce (ESBVRD) is an anomaly that leads to reduced growth and, in more extreme cases, to death of eucalyptus plants. Initially diagnosed in plantations in the region of the Vale do Rio Doce, in the State of Minas Gerais, Brazil, this problem has also been found in plantations in other regions of the country and even in other countries. Although the symptoms of this anomaly are well-known, its causes are not yet understood. The aim of this study was to evaluate the cause-effect relationship between accumulation of manganese (Mn) in eucalyptus clones and ESBVRD. Characterization of the environment in areas of greater occurrence of this problem in regard to soil, climate and fluctuation of the water table was undertaken in eucalyptus plantations of the Celulose Nipo-brasileira S.A. (Cenibra) company in the region of the Vale do Rio Doce. Plant tissues were sampled in two situations. In the first situation, diagnosis occurred in the initial phase of the anomaly in clones with differentiated tolerance to the problem; in the second situation, diagnosis was made in a single clone, considered to be sensitive, in two time periods - in the phase with the strong presence of symptoms and in the recovery phase, in areas of occurrence and in areas of escape from the problem. The most ESBVRD-sensitive clone showed much higher (4.8 times higher) leaf Mn contents than more tolerant clones. In plants with the anomaly, Mn leaf contents were greater than 3,070 mg kg-1, much greater than the quantity found in those without the anomaly (734 mg kg-1). In the period in which the symptoms began to wane, there was a sharp decline in leaf Mn contents, from 2,194 to 847 mg kg-1. Manganese content in the above ground part and plant litter (44.4 g ha-1) in the area of occurrence of the anomaly was three times greater than that found in these same components (14.1 g ha-1) in the area of absence of the symptom. Based on the evidence found, such as the existence of environmental conditions favorable to high Mn availability to the plants in the areas of greatest incidence of ESBVRD, greater uptake of Mn in sensitive clones and in plants with symptoms, and a synchronism between the intensity of symptoms of ESBVRD and leaf Mn contents, it may be inferred that temporary excess of Mn in eucalyptus plants is closely related to ESBVRD.

[9 phot. de Madagascar entre 1867 et 1900, 2 phot. par A. et G. Grandidier. Enregistré en 1970]

Comprend : Andakama sur le Mangoro, à 60 km à l'est de Tananarive. ; Femme Sakalava, vers Tulear. ; Sakalave. ; Forêt dans l'est de Madagascar. ; Sakalava from W.coast. ; VillageVangaindrano (sur le bord du Mananara) ; fort Merina (hova), côte sud-est. ; Campement du commandant Lyautey et le mien, aux environs de Fort Dauphin, en 1900. ; Madagascar : Imerina, charrue.

Las investigaciones de Leo Frobenius y el Forschungsinstitut für Kulturmorphologie (FK) sobre el arte rupestre en España (1934-1936).

Leo Frobenius, fundador del Afrika Archiv y director del Forschungsinstitut für Kulturmorphologie (FK), centró la mayor parte de su actividad etnográfica en la documentación y estudio del arte rupestre. Tras estudiar las obras de Hugo Obermaier sobre el arte parietal en la Península Ibérica, decidió, en 1934, organizar una expedición para documentar los principales yacimientos francocantábricos y del Levante español. En ella se estudiaron tan sólo los yacimientos de Roca dels Moros de Cogul y el Barranco de la Valltorta, pero sirvió de base para la programación de una nueva expedición cuyos objetivos eran mucho más ambiciosos. En 1935, con la ayuda de Obermaier, Bosch Gimpera y Martínez Santa Olalla, y el amparo diplomático de la Embajada de Alemania en Madrid, realizó la petición de acceso a las principales cuevas con arte parietal, permiso que consiguió tras arduas negociaciones. En los meses previos al inicio de la Guerra Civil, un grupo de dibujantes y fotógrafos del FK trabajó en las cuevas de El Castillo, La Pasiega y Altamira, obteniendo copias a escala natural de grabados y pinturas que pasaron a formar parte del archivo del Instituto. En 1938, y como consecuencia del apoyo de Alemania al bando nacional, Martínez Santa Olalla, miembro de la Falange, se convirtió en el referente de Frobenius en España, desplazando a Obermaier. Dicha relación tendría como consecuencia el giro en la política arqueológica de los vencedores de la contienda y su vinculación con la organización Das Ahnenerbe de las SS.

Décret du 6 mars 1934 relatif à la réforme des études médicales

[Décret. 1934-03-06]