Quantificação de fluxos de mercúrio gasoso na interface solo/atmosfera utilizando câmara de fluxo dinâmica: aplicação na bacia do Rio Negro

Gaseous mercury sampling conditions were optimized and a dynamic flux chamber was used to measure the air/surface exchange of mercury in some areas of the Negro river basin with different vegetal coverings. At the two forest sites (flooding and non-flooding), low mercury fluxes were observed: maximum of 3 pmol m-2 h-1 - day and minimum of -1 pmol m-2 h-1 - night. At the deforested site, the mercury fluxes were higher and always positive: maximum of 26 pmol m-2 h-1 - day and 17 pmol m-2 h-1 - night. Our results showed that deforestation could be responsible for significantly increasing soil Hg emissions, mainly because of the high soil temperatures reached at deforested sites.

Lingüística e arqueologia

This retrospective paper will shed light on the relations between Linguistics and Archaeology by drawing special attention to the history of Archaeology and the influence of Linguistic models for the development of archaeological interpretive frameworks. Reference will be made to culture history theoreticians, like Gordon Childe, to processual archaeologists influenced by Structuralism and to post-processual discourse analysis. The paper will conclude stressing the importance of Linguistics to archaeological thought.

A lingüística indígena no Brasil

This article presents a panorama of the area of the linguistics of the indigenous languages in Brazil within the discipline of Brazilian linguiistics as a whole. Special attention is given to those aspects related to its specific development. It is argued that in contrast to what is commonly supposed, the arrival of the Summer Institute of Linguistics (1959) not only was not the beginning of this area of study in the country, but it even contributed to the delay in its establishment. It was only after the return of Brazilian scholars educated abroad who were interested in the study of the national indigenous languages that a specialized branch of linguistics directed to the study of these languages began to take form. The present situation of the area and perspectives for future development are both explored.

Lingüística textual: quo vadis?

This paper aims to discuss the future -- and the proper survival of Textlinguistics this millenium, and the challenges it has to face in order to contribute to the development of Human Sciences in a new era.

Por uma lingüística crítica: linguagem, identidade e questão ética

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