Chemical amendment of dairy cattle slurry has been shown to effectively reduce incidental phosphorus (P) losses in runoff; however, the effects of amendments on incidental nitrogen (N) losses are not as well documented. This study examined P and N losses in runoff during three simulated rainfall events 2, 10 and 28 days after a single application of unamended/chemically amended dairy cattle slu...

This study was conducted to measure the effects of slurry application method, swine growth stage, and flow rate on runoff nutrient transport. Swine slurry was obtained from production units containing grower pigs, finisher pigs, or sows and gilts. The swine slurry was applied using broadcast, disk, or injection methods at a rate required to meet annual nitrogen requirements for corn. Three 30 m...

Agricultural runoff often contains pollutants with antagonistic impacts. The individual influence of nutrients and atrazine on periphyton has been extensively studied, but their impact when introduced together and with multiple agricultural pollutants is less clear. We simulated a field-scale runoff pulse into a riverine wetland that mimicked pollutant composition typical of field runoff of the...

Computer simulation models are essential tools for evaluating soil erosion potential over large areas of cropland. Small-plot and field-scale evaluations are commonly conducted for federal farm program compliance, but producers are now faced with off-farm water quality concerns. Predicting the potential contribution of upland sediment is of interest to producers and state and federal agencies. ...

Water changes information in the hydrological system, in time and space, as an environmental issue takes heed of managers and decision makers in watershed management and river engineering, which can be addressed by using spatially distributed modeling. In this study simulation of water balance components in Taleghan mountainous watershed is performed using the spatially distributed hydrological...

A one-dimensional model, SOIL/SOILN_NO is used to simulate the water and N balance at the catchment scale. The catchment is characterized by a large number of farm fields with a high degree of variability, both in crop type, fertilizer application, yield level and soil type. The model was not applied to individual fields but instead a lumped approach was chosen in which the number of crops was ...

The application of hydrological and water quality models is an efficient approach to better understand the processes of environmental deterioration. This study evaluated the ability of the Annualized Agricultural Non-Point Source (AnnAGNPS) model to predict runoff, total nitrogen (TN) and total phosphorus (TP) loading in a typical small watershed of a hilly region near Taihu Lake, China. Runoff...

Little information is currently available concerning temporal changes in nutrient transport following the addition of manure to cropland areas. This study was conducted to measure nutrient transport in runoff as affected by tillage and time following the application of beef cattle or swine manure to a site on which corn (Zea mays L.) was grown. Rainfall simulation tests were initiated 4, 32, 62...

Due to a shortage of available phosphorus (P)-loss datasets, simulated data from an accurate quantitative P transport model could be used to evaluate a P Index. The objective of this study was to compare predictions from the Texas Best Management Practice Evaluation Tool (TBET) against measured P-loss data to determine whether the model could be used to improve P Indices in the southern region....

Field and laboratory studies have indicated that rock fragments in the topsoil may have a large impact on soil properties, soil quality, hydraulic, hydrological and erosion processes. In most studies, the investigated rock fragments still remain visible at the soil surface and only properties of these visible rock fragments are used for predicting runoff and soil loss. However, there are indica...