This study suggests the employment of accumulated sediments in the reservoir of Tucuruí (Pará /Brazil) to remineralize the surrounding degraded soils. The approach was based on the principles of stonemeal technology. It suggests that the soil can be rejuvenated by crushed rocks rich in macro and micronutrients. Removal of the sediments for agricultural use will bring benefits to family farmers and increase the life cycle of the reservoir and, therefore, energy generation. Geochemical data on retained sediments, soils and rocks in the area of influence of the reservoir were evaluated regarding nutrient transport mechanisms and soil-fertility potential. Results show that sediments from the reservoir contain nutrients levels at least one order of magnitude greater than average Amazon region soils. Our data on soil use and occupation in the region show the degradation areas which could be recovered by stonemeal techniques. Thence, an Agroforestry System was installed, with 12 plots where different mixtures of sediments removed from the reservoir were used, along with crushed rock with or without the addition of NPK and manure. The experiments showed that maximum crop yield and plant growth were attained in the plots where a mixture of sediments, crushed rocks and manure were added.

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RESUMO -A quantidade de catalisador(A), temperatura (B) e pressão (C) da reação foram estudas segundo planejamento experimental do tipo Box-Benken em 3 níveis para avaliar seus efeitos no processo de produção de sorbitol por meio da conversão catalítica da glicose. As reações foram conduzidas em um reator do tipo autoclave (Parr) na presença de catalisador a base de rutênio. Os resultados indicam que quantidade de catalisador e temperatura apresenta influências linear e quadrática, enquanto a pressão contribui apenas linearmente. Além do que, a concentração de catalisador é o fator de maior influência, sendo desejável utilizar concentrações entre 0,016 e 0,024 g/cm 3 . Os três fatores (A, B e C) exerceram influência sobre o rendimento, porém a seletividade apresentou-se invariavelmente em 100%.