%0 Journal Article %J Oecologia %D 2004 %T Carbon and nitrogen stoichiometry and nitrogen cycling rates in streams %A W. K. Dodds %A Marti, E. %A Tank, J. %A Pontius, J.L. %A Hamilton, S.K. %A Grimm, N.B. %A W.B. Bowden %A W.H. McDowell %A Peterson, B.J. %A Valett, H.M. %A Webster, J.R. %A Gregory, S. %K carbon %K Carbon:Nitrogen ratio %K nitrogen %K stoichiometry %K streams %X Stoichiometric analyses can be used to investigate the linkages between N and C cycles and how these linkages influence biogeochemistry at many scales, from components of individual ecosystems up to the biosphere. N-specific NH4 + uptake rates were measured in eight streams using short-term 15N tracer additions, and C to N ratios (C:N) were determined from living and non-living organic matter collected from ten streams. These data were also compared to previously published data compiled from studies of lakes, ponds, wetlands, forests, and tundra. There was a significant negative relationship between C:N and N-specific uptake rate; C:N could account for 41% of the variance in N-specific uptake rate across all streams, and the relationship held in five of eight streams. Most of the variation in N-specific uptake rate was contributed by detrital and primary producer compartments with large values of C:N and small values for N-specific uptake rate. In streams, particulate materials are not as likely to move downstream as dissolved N, so if N is cycling in a particulate compartment, N retention is likely to be greater. Together, these data suggest that N retention may depend in part on C:N of living and non-living organic matter in streams. Factors that alter C:N of stream ecosystem compartments, such as removal of riparian vegetation or N fertilization, may influence the amount of retention attributed to these ecosystem compartments by causing shifts in stoichiometry. Our analysis suggests that C:N of ecosystem compartments can be used to link N-cycling models across streams. %B Oecologia %V 140 %P 458 -467 %G eng %M KNZ00925 %R 10.1007/s00442-004-1599-y