A watershed management program is usually based on the results of watershed modeling. Accurate modeling results are decided by the appropriate parameters and input data. Precipitation is the most important input for watershed modeling. Precipitation characteristics usually exhibit significant spatial variation, even within small watersheds. Therefore, properly describing the spatial variation o...

This supplemental material section contains detailed information on the input data assumptions for the SWAT modeling as well as the model calibration and validation results. The data sources listed in Supplemental Table 1 were used to build the SWAT TMDL modeling system for the Raccoon River watershed, most of which are accessible in the Iowa Department of Natural Resources (IDNR) on-line digit...

This study presents the results from evaluation of a hydrologic modeling workshop for 46 water resource decision makers in Hermosillo, Mexico. This region has serious, ongoing water quantity and quality problems. Our goals were to assess participants’ perceptions of our workshop and associated hydrologic and water quality models and to learn whether it changed their perceptions of local water r...

Hydrological models are used to represent the rainfallrunoff and pollutant transport mechanisms within watersheds. Accurate representation of these dynamic and complex natural processes within a watershed is an important step in managing and protecting a watershed Artificial neural network (ANN) models are often used in hydrologic modeling. Typical ANN models are trained to use lumped data. How...

Complicated research and management questions regarding watershed systems often require the use of more than one simulation model. Therefore, it is necessary to develop a means to integrate multiple simulation models to predict holistic system response. In this paper we explore the use of a componentbased approach for the runtime integration of models, implemented as “plugand-play” software com...

Watershed models have been widely used for creating the scientific basis for management decisions regarding nonpoint source pollution. In this study, we evaluated the current state of watershed scale, spatially distributed, process-based, water quality modeling of nutrient pollution. Beginning from 1992, the year when Beven and Binley published their seminal paper on uncertainty analysis in hyd...

abstract spatial variability of soils makes difficult analysis of soil water flow phenomena especially in a large area such as a watershed. using scaling methods is a solution in variability problems. the objective of this study was to investigate the effect of the non-linear variability on performance of the scaling methods of richards’ equation for modeling infiltration in a watershed. the me...

Nitrogen (N) uptake in streams is an important ecosystem service that reduces nutrient loading to downstream ecosystems. Here we synthesize studies that investigated the effects of urban stream burial on N-uptake in two metropolitan areas and use simulation modeling to scale our measurements to the broader watershed scale. We report that nitrate travels on average 18 times farther downstream in...