We evaluated the impacts of natural wetlands and various land uses on stream nitrogen concentration in two grassland-dominated catchments in eastern Hokkaido, Japan. Analyzing land use types in drainage basins, measuring denitrification potential of its soil, and water sampling in all seasons of 2003 were performed. Results showed a highly significant positive correlation between the concentrat...

Dissolved organic carbon concentrations ([DOC]) in surface waters are increasing in many regions of Europe and North America. These increases are likely driven by a combination of changing climate, recovery from acidification and change in severity of winter storms in coastal areas. INCA-C, a process-based model of climate effects on surface water [DOC], was used to explore the mechanisms by wh...

By increased rural-urban migration in many African countries, the assessment of changes in catchment hydrologic responses due to urbanization is critical for water resource planning and management. This paper assesses hydrological impacts of urbanization on two medium-sized Zimbabwean catchments (Mukuvisi and Marimba) for which changes in land cover by urbanization were determined through Lands...

Land use change is the most significant driver linked to global species extinctions. In Northern Australia, the landscape is still relatively intact with very low levels of clearing. However, a re-energized political discourse around creating a northern food bowl means that currently intact ecosystems in northern Australia could be under imminent threat from increased land clearing and water ex...

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...

introduction flood is an inevitable natural phenomenon occurring from time to time in all rivers and natural drainage systems, which not only damages the lives, natural resources and environment, but also causes the loss of economy and health. so estimation and prediction flood hazard is very important spatially in the watersheds without measurement station. there are many models in the water a...

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...

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...

Rainfall-runoff models are used for various applications, ranging from the estimation of catchment water yield to the estimation of land use and climate change impacts on runoff characteristics. Most rainfall-runoff models can be calibrated successfully to reproduce the recorded runoff, however it is difficult to determine appropriate parameter values to use for modelling runoff in an ungauged ...

This paper presents a new method of representing flow duration curves (FDC) using a logarithmic transformation. The FDC has been defined using two parameters – the ‘cease to flow’ point, and the slope of the FDC. This method for defining the FDC has been applied to 23 sub-catchments of the Burdekin River in North Queensland, Australia. The two parameters defining the FDC have been related to th...