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Skillful and reliable forecasts of seasonal streamflows are highly valuable to water management. In a previous study, we developed a Bayesian joint probability (BJP) modeling approach for seasonal forecasting of streamflows at multiple sites. The approach has been adopted by the Australian Bureau of Meteorology for seasonal streamflow forecasting in Australia. This study extends the applicability of the BJP modeling approach to streams with zero flow occurrences. The aim is to produce forecasts for these streams in the form of probabilities of zero seasonal flows and probability distributions of above zero seasonal flows. We turn a difficult mathematical problem of mixed discrete-continuous multivariate probability distribution modeling into one of continuous multivariate probability distribution modeling by treating zero flow occurrences as censored data. This paper presents the mathematical formulation and implementation of the modeling approach, methods for forecast verification, and results of a test application to the Burdekin river catchment in northern Queensland, Australia. [ABSTRACT FROM AUTHOR]

Interactions between catchment variables and sediment transport processes in rivers are complex, and sediment transport behaviour during high-flow events is not well documented. This paper presents an investigation into sediment transport processes in a short-duration, high-discharge event in the Burdekin River, a large sand- and gravel-bed river in the monsoon- and cyclone-influenced, semi-arid tropics of north Queensland. The Burdekin's discharge is highly variable and strongly seasonal, with a recorded maximum of 40 400 m3 s−1. Sediment was sampled systematically across an 800 m wide, 12 m deep and straight reach using Helley-Smith bedload and US P-61 suspended sediment samplers over 16 days of a 29-day discharge event in February and March 2000 (peak 11 155 m3 s−1). About 3·7 × 106 tonnes of suspended sediment and 3 × 105 tonnes of bedload are estimated to have been transported past the sample site during the flow event. The sediment load was predominantly supply limited. Wash load included clay, silt and very fine sand. The concentration of suspended bed material (including very coarse sand) varied with bedload transport rate, discharge and height above the bed. Bedload transport rate and changes in channel shape were greatest several days after peak discharge. Comparison between these data and sparse published data from other events on this river shows that the control on sediment load varies between supply limited and hydraulically limited transport, and that antecedent weather is an important control on suspended sediment concentration. Neither the empirical relationships widely used to estimate suspended sediment concentrations and bedload (e.g. Ackers & White, 1973) nor observations of sediment transport characteristics in ephemeral streams (e.g. Reid & Frostick, 1987) are directly applicable to this river. [ABSTRACT FROM AUTHOR]

Presents a corrected version of the article "Supply limited sediment transport in a high-discharge event of the tropical Burdekin River, North Queensland, Australia," by K.J. Amos, J. Alexander, A. Horn, G.D. Pocock and C.R. Fielding, which was published in a volume 51 issue of the periodical "Sedimentology."

The article presents an investigation on the relationship between habitat condition and the abundance and distribution of plague minnow on the Burdekin River floodplain in Queensland. It examined the variation in the abundance of plague minnow associated with habitat degradation and trials of mechanical weed removal. It is discovered in the investigation that the combined effects of reduced abundance of alien plague minnows and aquatic weed removal can improve the structure of fish community.