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Here we report on 3 years (1 1-15-25/xmol L-during base flow, increased to-30/xmol L-on the rising limb of the hydrograph during snowmelt runoff, then decreased to-5/xmol L-• on the recession limb of late summer, with a return to base flow values in the autumn. In contrast, organic N was 7-15/xmol L-• during base flow and decreased to near or below detection limits on the rising limb of the hydrograph, with a gradual but consistent increase on the recession limb and on into the autumn. The amount of N in dissolved organic matter changed over time, with the dissolved organic carbon (DOC):DON ratio decreasing from-45 on the rising limb of the hydrograph to <20 in the autumn. Spatially, there was a striking difference in the ratios of NO3-N and DON between talus and tundra areas. Nitrate concentrations in surface water draining talus areas were always greater than DON. In contrast, DON concentrations in surface water draining tundra areas were always greater than NO3-N. Concentrations of DON were not significantly correlated with DOC (R 2 = 0.04, p > 0.05), indicating that controls on DON export may be different than controls on DOC export. Our results suggest that the ratio of the annual mass flux of inorganic N to organic N in stream waters may provide a novel index to evaluate the N status of terrestrial ecosystems from various biomes. 1. Introduction The flux of dissolved organic matter (DOM) through terrestrial ecosystems plays an important role in soil formation and nutrient dynamics [McDowell and Wood, 1984; Neff et al., 2000]. Nevertheless, there is surprisingly little information on the magnitude of organic N fluxes relative to inorganic fluxes of NH4-N and NO3-N. Twenty years ago, Sollins and McCori-son [1981] emphasized that organic N must be measured if total N transfers are to be calculated because the only meaningful comparison is total N input versus output. To illustrate the potential importance of organic N, Seely and Lathja [1997] added •SNO•-to soils and reported that most of the isotopically labeled NO3-N left the system in the form of DON. Even less is known about the role of organic N in atmospheric deposition of wetfall and dryfall [Neff et al., 2001]. It has been

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The 1H-13C CP MAS NMR and Raman spectra of N,N,N,N ‘ ,N ‘ ,N ‘-hexaethylpentanediammonium (Et6-diquat-5) ions encapsulated within P1, SUZ-4, and ZSM-57 zeolites are presented. The Et6-diquat-5 molecules occluded are found to adopt distinct molecular conformations in order to fit in the pores of each zeolite host. Computer modeling studies show that encapsulation of Et6-diquat-5 in the small-pore zeolite P1 is not energetically favorable. However, a remarkable match between the conformation of guest molecule and the geometry of the host structure is observed for the medium-pore zeolites SUZ-4 and ZSM-57, revealing the existence of organic structure-directing effect. The overall results of this study suggest that conformations available to the flexible, linear organic cation like Et6-diquat-5 may differ considerably according to the type and concentration of alkali cations present in the zeolite synthesis mixture, which is a critical factor affecting the phase selectivity of the crystallization. It thus appears that the modification of conformations of flexible organic structure-directing agents by varying the type and concentration of alkali cations may be an area of considerable possibility for finding new zeolite structures.