Recent and future river basin management requires a more spatially distributed description of basin hydrology and nutrient transport processes to enable land use management as a process controlling factor to realize sound river basin management. The spatial description of these processes in the Soil and Water Assessment Tool (SWAT) watershed model is presently realized by aggregating the flows ...

Trends in concentration and loads of acetochlor, alachlor, and metolachlor and their ethanasulfonic (ESA) and oxanilic (OXA) acid degradates were studied from 1996 through 2006 in the main stem of the Iowa River, Iowa and in the South Fork Iowa River, a small tributary near the headwaters of the Iowa River. Concentration trends were determined using the parametric regression model SEAWAVE-Q, wh...

River basin sediment loads are affected by several factors, with flood magnitude and watershed erosional stability playing dominant and dynamic roles. Long-term average sediment loads for northern California river basins have been computed by several researchers by several methods. However, characterizing the dynamic nature of climate and watershed stability requires computation of annual loads...

The South-to-North Water Transfer (SNWT) Project of China is the largest of its kind ever implemented. Of its three routes (i.e., East, Middle and West), the middle one will transfer 14 billion m(3) of water annually from the Han River, a tributary of the Yangtze and the water supplying area, to Beijing by 2030. Thus water quality in the 95,000 km(2) upper Han River basin is of great concern. A...

A mass balance was assembled for perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), perfluorodecanoic acid (PFDA), and perfluorooctanesulfonic acid (PFOS) in the Baltic Sea. Inputs (from riverine discharge, atmospheric deposition, coastal wastewater discharges, and the North Sea) and outputs (to sediment burial, transformation of the chemical, and the North Sea), as well as the inve...

The analysis of changes in water quality in a monitoring network system is important because the sources of pollution vary in time and space. This study utilized analysis of the water quality index calculation, hierarchical cluster analysis, and mapping. This was achieved by assessing the water quality parameters of the samples collected from Galma River in Zaria, Northwestern Nigeria in wet an...

Recently, a manuscript was published with the objective to complete a multivariable and multisite calibration and validation for the Soil and Water Assessment Tool (SWAT) model on the Motueka River basin by Cao et al. (2006). Physically based distributed parameter models, such as SWAT, have become a preferred tool to predict watershed response not only at the watershed outlet, but also at inter...

The fishes and invertebrates of the Cosumnes River basin and its floodplain were intensively studied from 1999 through 2002 to determine their basic distribution, abundance, and ecology. The purpose of the studies, done in conjunction with studies on fluvial geomorphology, water chemistry, and other aspects of the physical and chemical environment, was to develop the information needed for mana...

A freshwater fish inventory was conducted from March through August, 2002 in the Alagnak Watershed. The objectives of the inventory were (1) to document species that were expected yet undocumented and (2) to provide initial descriptions of the distributions, abundance, and biologic characteristics of these species. Minnow traps, minnow seines, beach seines, snorkel gear, hand nets, fyke nets, t...

The main purpose of the study is determination of the pollutants hazard potential as well as environmental vulnerability of Qarah Su River. First the most significant pollutant sources in the Qarah Su river watershed were identified and then accordingly the pollution hazard potential rate was calculated in Universal Ranking System Model setting. Then, by generalizing the algebraic sum of the re...