『Abstract
　This study investigated the storage of nitrogen (N) and phosphorus (P) in he biomass, bed sediments and water column of representative reaches of a sub-tropical river, the upper Brisbane River (UBR), Queensland, Australia, and contrasted instream storage with total wet season exports. In reaches which contained accumulated fine sediments, more than 87％ of total P and between 50％ and 92％ of total N were stored in the surface sediments. The lower proportion of n in sediment at some sites was attributed to substantial differences in the N/P ratios of sediments and macrophytes. At one site, the riverbed was dominated by cobbles and boulders and total nutrient stocks were comparatively low and dominated by the biomass. In reaches with a narrow channel and intact riparian cover, biomass N and P were stored predominately in leaf litter, while in wider unshaded reaches, macrophytes dominated. Total instream storage in the mid to lower reaches of the UBR was 〜50.9 T for N and 〜18.1 T for P. This was considerably higher than total wet season N (〜15.6 T) and P (〜2.7 T) exports from the UBR. The first flow event in the river after a prolonged period of no flow resulted in the export of free-floating, emergent species Azolla. The estimated biomass of Azolla in the mid to lower reaches of the river was equivalent to approximately 24％ and 9％ of the total N and P flux, indicating that this may be a significant, previously unaccounted for, source at peak flow.

Keywords: Nitrogen; Phosphorus; Rivers; Sediment; Macrophytes』

1. Introduction
　1.1. The upper Brisbane River catchment
2. Methods
　2.1. Location of study sites and flow conditions during the study period
　2.2. characterisation of reach geomorphology
　2.3. Water column sampling and analysis
　2.4. sampling and analysis of macrophyte, leaf litter, periphyton and sediment
　2.5. Estimation of C, N and P storage in biomass, sediment and water column pools
　2.6. Estimation of N and P exports during the study period
3. Results and discussion
　3.1. The effect of reach-scale geomorphology on nutrient partitioning
　3.2. Comparison of total nitrogen and phosphorus storage in reaches of the upper Brisbane River and tributaries
　3.3. The effect of a flow event on macrophyte biomass in he UBR (UBRA)
　3.4. Comparison of wet season N and P loads with instream N and P storage
4. Conclusion
Acknowledgements
References