Transit time is a fundamental catchment descriptor that reveals information about storage, flow pathways and source of water in a single characteristic. Given the importance of transit time, little guidance exists for the application of transit time modeling in complex catchment systems. This paper presents an evaluation and review of the transit time literature in the context of catchments and...

The development and increasing availability of global environmental data sets provides an opportunity to examine systematically the relationship between sediment yields and controlling catchment variables, employing Geographical Information Systems. Few studies have attempted to harness such information to analyse variations in sediment yields within large catchments. Sediment yields from 62 lo...

Addressing environmental management problems at catchment scales requires an integrated modelling approach, in which key bio-physical and socio-economic drivers, processes and impacts are all considered. Development of Decision Support Systems (DSSs) for environmental management is rapidly progressing. This paper describes the integration of physical, ecological, and socio-economic components i...

[1] The effects of catchment size and landscape organization on runoff generation are poorly understood. Little research has integrated hillslope and riparian runoff investigation across catchments of different sizes to decipher first-order controls on runoff generation. We investigated the role of catchment sizes on riparian and hillslope dynamics based on hydrometric and tracer data observed ...

Catchment contaminant loads vary with stream order as catchment characteristics influence inputs and in-stream processing. However, the relative influence and policy significance of these characteristics across a number of contaminants and at a national scale is unclear. We modeled the significance of catchment characteristics (e.g., climate, topography, geology, land cover), as captured by a n...

The application of fallout radionuclides in soil erosion and sedimentation investigations has provided a valuable tool for improving the understanding of erosion and sediment transfer processes. However, most studies using fallout radionuclides have focussed on small areas. Increasing acceptance of the important role of fine sediment in degrading aquatic habitats and in the transfer and fat...

Many models of phosphorus (P) transfer at the catchment scale rely on input from generic databases including, amongst others, soil and land use maps. Spatially detailed geochemical data sets have the potential to improve the accuracy of the input parameters of catchment-scale nutrient transfer models. Furthermore, they enable the assessment of the utility of available, generic spatial data sets...

The integrity of the Blesbok Spruit catchment has been significantly compromised over the past decades, mainly due to the discharge of mining effluent and sewage. This research investigated the hydrological responses, in terms of water quality, in the event of land cover change within the catchment to make predictions on the future sustainability of the region’s water resources with the applica...

1. Riparian zones function as important ecotones that reduce nitrate concentration in groundwater and inputs into streams. In the boreal forest of interior Alaska, permafrost confines subsurface flow through the riparian zone to shallow organic horizons, where plant uptake of nitrate and denitrification are typically high. 2. In this study, riparian zone nitrogen retention was examined in a hig...