Eutrophication of coastal oceans as a result of the delivery of excess nutrients by rivers is a critical environmental issue on local, regional, and global scale. Japanese agriculture has created high nitrogen surpluses in agricultural lands due to the increasing rate of chemical fertilizer application and the increase of livestock. In this study, to estimate the nitrogen load exported to Koise...

This is the first global assessment of nitrogen-related water pollution in river basins with a specification of the pollution by economic sector, and by crop for the agricultural sector. At a spatial resolution of 5 by 5 arc minute, we estimate anthropogenic nitrogen (N) loads to freshwater, calculate the resultant gray water footprints (GWFs), and relate the GWFs per river basin to runoff to c...

[1] Diurnal cycles in snow-fed streams provide a useful technique for measuring the time it takes water to travel from the top of the snowpack, where snowmelt typically peaks in the afternoon, to the river gauge, where the daily maximum flows may arrive many hours later. Hourly stage measurements in nested subbasins (6–775 km) of the Tuolumne River in Yosemite National Park illustrate travel ti...

The Middle Fork Salmon River watershed spans high-elevation mixed-conifer forests to lowerelevation shrub-steppe. In recent decades, runoff from severely burned hillslopes has generated large debris flows in steep tributary drainages. These flows incised alluvial fans along the mainstem river, where charcoal-rich debris-flow and sheetflood deposits preserve a record of latest Pleistocene to Hol...

Restriction fragment length polymorphism (RFLP) analysis of mitochondrial DNA (mtDNA) was employed to characterize species and populations of Astyanax, a Neotropical freshwater fish genus. Samples of five species, A. altiparanae, A. fasciatus, A. lacustris, A. scabripinnis paranae and A. schubarti, from the Upper Paraná and São Francisco river basins were analyzed. Two out of the ten restrictio...

The target basins of this project are located in the Mekong River Basin across the toposequence (northern Thailand, northeast Thailand, Mekong Delta in Vietnam). An additional site is located in Bhutan. In these basins, diverse stakeholders with differing perceptions of water dynamics adopt various strategies to cope with the problems. There is a need, therefore, to understand the factors influ...

Impacts of land cover changes on watershed hydrology have been a long-term academic concern with acute dispute. But little attention has been paid to such effects on mesoscale river basins, where the society has a closer link to river hydrology. The present study focuses on a mesoscale river basin, the Suomo Basin that is located on the upper reaches of the Yangtze River. Land covers in the bas...

Realistic estimates of daily streamflow and water temperature are required for effective management of water resources (e.g. for electricity and drinking water production) and freshwater ecosystems. Although hydrological and process-based water temperature modelling approaches have been successfully applied to small catchments and short time periods, much less work has been done at large spatia...

During the Cenozoic, Southeast Asia was profoundly affected by plate tectonic events, dynamic river systems, fluctuating sea levels, shifting coastlines, and climatic variation, which have influenced the ecological and evolutionary trajectories of the Southeast Asian flora and fauna. We examined the role of these paleogeographic factors on shaping phylogeographic patterns focusing on a species ...

Many river basins throughout the world are increasingly under pressure as water demands keep rising due to population growth, industrialization, urbanization and rising living standards. In the past, the typical answer to meet those demands focused on the supply side and involved the construction of hydraulic infrastructures to capture more water from surface water bodies and from aquifers. As ...