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We used nondisruptive, whole-stream methods to measure hydraulic characteristics, ecosystem metabolism, and phosphorus cycling in the west fork of Walker Branch (WE), Tennessee and in Hugh White Creek (HWC), North Carolina. Although similar in many of their hydrological and chemical characteristics, transient storage zone volume in HWC was relatively large (similar to 1.5 times that of the flowing water zone), whereas transient storage zone volume in WE was small (similar to 0.1 times that of the flowing water zone). Both streams were highly heterotrophic (gross primary production:total respiration ratios <0.1), although respiration rate was similar to 2.4 times greater in HWC than in WE. Phosphorus uptake rate was similar to 2.6 times, greater in HWC than in WE, and P uptake length was 5 times longer in WE than in HWC. Analysis of P-33:H-3 ratio profiles from (PO4)-P-33 and (H2O)-H-3 injection experiments indicated that P uptake within the transient storage zone accounted for similar to 43% of the total P uptake in HWC but was negligible in WE, explaining, in part, the difference in total P uptake rate between these streams. The higher rate of P uptake in the surface zone, shorter P uptake length, and larger ratio of P uptake:respiration in HWC compared with WE suggest that the microbial community in HWC exerts a greater demand for and has a greater affinity for streamwater P presumably as a result of a greater supply of labile organic matter and/or lower nutrient levels in HWC.