Koenings, ). P., H. ). Geiger, and 1. 1. Hasbrouck. 1993. Smolt-to-adult survival patterns of sockeye salmon (Oncorhynshus nerka): effects of smolt length and geographic latitude when entering the sea. Can. 1. Fish. Aquat. Sci. 50: 600-61 1. Variations in smolt-to-adult survival (SAS) of sockeye salmon (Oncorhynchus nerka) relative to smolt length and age and latitude of the nursery Bake outlet were explored for six stocks in Canada, Russia, and Alaska (W. E. Ricker. 1962. ). Fish. Res. Board Can. 19: 537-5601 and 12 Alaskan populations. SAS values ranged from <1 to 68% for age 1 ., 2., and 3. smolt populations of 54-200 mm in mean length. The common pattern underlying the SAS to smolt sine relationship, determined by nonparametric regression (loess), was nonlinear with f~snction-ally distinct zones. SAS of smaller smolts increased (0.3-0.5 (%) SAScmrn -') with size, but SAS of smolts >90-100 mm (6-8 g) did not. Variation in SAS was explained by srnolt sine (30%) and a south to north cline of nursery lakes (21 %j indexed by latitude. SAS of about 3 and 13% for threshold-sized age 1. smolts (60-65 mm) from southern and northern nursery lakes were consistent with sockeye biostandards for Canada (4.7%) and Alaska (1 2%1, respectively. The combined effects of latitude and smolt length on SAS resulted in larger smolts at higher (>60QN) latitudes having seven times the SAS sf smaller smolts at lower (<5%'N! latitudes. Chez six stocks trouvks au Canada, en Russie et en Alaska et qui ont dkja eke analyses par W. E. Ricker (1962. j. can. sci. halieut. aquat. 19 : 531-5630), ainsi que chez 12 populations d'Alaska, on a examine les variations de la survie du saumsneau a l'adulte ISSA) chez le saumon rouge (Oncorhynchus nerka) en fonctisn de la longueur et de I'2ge des saumoneaux, ainsi que de I'emplacenient de I'exutoire du lac d'alevinage. La SSA variait entre moires de 1 et 68 % dans les pop~slations de saumoneaux mesurant 54-200 mm de longueur moyenne et Ag6s de 1 ., 2. et 3. ares. Telle que deterrninke par une regression now parametrique (loess), I'allure commune de la relation entre la SSA et la taille des saumoneaux etait non lineaire et com~portait des zones fonctionnellement distinctes. La SSA des plus petits saumoneaux s'accroissait proportionnellement 2 la taille (0,3-0,5 (%) SSAamm-I), mais ce n16tait pas le cas de la SSA des saumoneaux de plus de 90-1 00 m m (6-8 g). bes variations de la SSA s'expliquaient par la ta~lle des saumoneaux (30 %) et I'existence d'un clivage, orient6 du sud au nord, des lacs d'alevindge (21 %) exprime en fonction de la latitude. La SSA d'environ 3 et 13 % chef les saumoneaux de taille minimale et 2gks de 1. an (60-65 mm) qui provenaient des lacs d'alevinage du sud et du nord etait conforme aux standards biollogiques du saumon rouge au Canada (4,7 %) et en Alaska (1 2 %), respsctivement. L'effet combink de la latitude et de la longueur des saumoneaux sur la SSA explique que les plus gsos saumoneaux des hautes latitudes (>60 "N) ont une SSA sept fois supkrieure A celle des petits sauni...

The relationship between iron and phosphorus and the relationship of these elements to colloidal organic matter (COM ) was studied in a meromictic acid bog lake by chemical characterization, filtration and in situ dialysis, and in situ experiments with labeled components.Bathophenanthroline ( BPN ) rcactivc ferrous iron existed in true solution ( dialyzable ) in constantly anaerobic monimolimnetic water; iron was of colloidal size.

A sampler and an analytical and characterization scheme were developed to investigate the chemical and physical state of iron in a highly stained acid bog lake (North Gate Lake). Iron fractions were chemically separated by reactivity to bathophenanthroline (BPN) after specific digestion procedures. Physical separation by anaerobic in situ filtration (450 nm) and in situ dialysis (4.8 nm) resulted in three size classes: particulate, colloidal, and dissolved. Inorganic, nonreactive species of iron [e.g. Fe(OH)3] represent minor amounts of the total iron in North Gate Lake, in contrast to lakes of pH 6–8. In situ radiochemical analyses revealed that colloidal reactive ferric iron predominates in the oxygenated epilimnion, while dialyzable or dissolved ferrous iron increases with depth. Unlike iron, organic matter is present in a nontransient colloidal state. In acid (pH 4–5) bog lakes ferric iron may be colloidal not as an inorganic complex (OH‒) but as reactive Fe3+ by complexation with the colloidal organic acids. After thermally induced mixing with anaerobic waters, ferric iron is reduced and dissolved; however some of the BPN reactive iron remains colloidal, suggesting the presence of a residual ferrous organic complex.

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