Abstract.A boreal deciduous forest in Saskatchewan, Canada, sequestered 144i65, 80i60, 116-t-35 and 290-t-50 g C m -2 y-• in 1994, 1996, 1997 and 1998, respectively. The increased carbon sequestration was the result of a warmer spring and earlier leaf emergence, which significantly increased ecosystem photosynthesis, but had little effect on respiration. The high carbon sequestration in 1998 was coincident with one of the strongest E1 Nifio events of this century, and is considered a significant and unexpected benefit.

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The local flow structure in a slot-rectangular spouted bed column of 300 mm × 100 mm cross-section was investigated with slots of equal area but different length-to-width ratios. Dead-zones, spout shapes, and distributions of pressure, particle velocity, and voidage were explored. The local flow structure of the slot-rectangular spouted bed became similar to conventional spouted beds as the height increased, with spouts from slots of different length-to-width ratios approaching similarity in the upper part of the bed. Static bed height was found to have little influence on the flow in the spout at a given level.On aétudié la structure d'écoulement local dans une colonneà lit jaillissant rectangulaireà fentes d'une section transversale de 300 mm × 100 mm, les fentesétant de surfaceégale mais les rapports longueur sur largeur différents. Les zones mortes, les formes de bec et les distributions de pression et de vitesse des particules ainsi que le degré de vide ontété explorés. La structure d'écoulement local du lit jaillissantà fentes rectangulaires devient semblableà celle des lits jaillissants conventionnels lorsque la hauteur augmente, les jets des fentes de différents rapports longueur sur largeur approchant une similarité dans la partie supérieure du lit. On a trouvé que la hauteur de lit statique avait peu d'influence sur l'écoulement dans le jetà un niveau donné.

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We introduce a fast computational method for feature selection that facilitates the accurate spectral analysis of a chemical species of interest in the presence of overlapping uncorrelated variance. Using a genetic algorithm in a data-driven approach, our method assigns predictors according to a template determined to minimize prediction variance in a calibration space. This template-oriented genetic algorithm (TOGA) efficiently establishes features of greatest significance and determines their optimal combination. We demonstrate the efficacy of TOGA using an elementary model system in which we seek to quantify a target monosaccharide in mixtures containing other sugars added in random amounts. The results establish TOGA as an effective and reliable technique for isolating signature spectra of targeted substances in complex mixtures.