Hancock,G.R.(2009): A catchment scale assessment of increased rainfall and storm intensity on erosion and sediment transport for Northern Australia. Geoderma, 152, 350-360.

『北部オーストラリアにおける増加した降水と暴風雨の浸食と堆積物運搬に対する流域規模の影響評価』


Abstract
 In recent years there has been a focus on the impact of changing climate on rainfall and storm patterns both globally and in Australia with research directed to examine how the global hydrological cycle will respond to climate change. This study investigates the effect of different rainfall patterns on erosion and sediment transport rates in a small study catchment in the Northern Territory, Australia. There have been several studies of the effect of climate change on rainfall patterns in the study area with projections indicating an increase in storm activity. Therefore it is important that the impact of this variability be assessed in terms of catchment hydrology, geomorphology and sediment transport and erosion rates. In this study a numerical model of erosion and deposition (CAESAR) is used to assess several different rainfall scenarios over a 1000 year modelled period. The results show that at the end of a 1000 year modelled period the simulated catchments are not geomorphologically or hydrologically different from one another. The model results reveal that increased rainfall amount and intensity increases sediment transport rates but predicted annual sediment output from the models was variable and non-linear but within the range of measured field data foe the catchment and region. The study provides a sensitivity analysis of both initial soil particle size distribution used in the erosion model and rainfall on long-term erosion rates and catchment sediment transport.

Keywords: Sediment transport; Hydrology; Geomorphology; Soil erosion modelling; CAESAR; Climate change; Climate variability』

1. Introduction
2. Study site
3. The CAESAR landscape and erosion model
4. Model input parameters
 4.1. Soil particle size and soil creep data
 4.2. Catchment digital elevation model
 4.3. Rainfall data
5. Methods and results
 5.1. Catchment geomorphology
 5.2. Erosion rates and patterns
6. Discussion
 6.1. Catchment geomorphology
 6.2. Erosion rates and patterns
7. Conclusion
Acknowledgments
References


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