Determining the survival of zoonotic pathogens in livestock manure and runoff is critical for understanding the environmental and public health risks associated with these wastes. The occurrence and persistence of the bacterial pathogens Escherichia coli O157:H7 and Campylobacter spp. in a passive beef cattle feedlot runoff control-vegetative treatment system were examined over a 26-mo period. ...

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...

Current vegetable production systems use polyethylene (plastic) mulch and require multiple applications of agrochemicals. During rain events, runoff from vegetable production is enhanced because 50 to 75% of the field is covered with an impervious surface. This study was conducted to quantify off-site movement of soil and pesticides with runoff from tomato (Lycopersicon esculentum Mill.) plots ...

Significant advances in upland erosion modeling have been achieved in the past decade. The TREX (Two-dimensional Runoff, Erosion, and Export) watershed model has been developed at Colorado State University for the simulation of surface runoff from spatially and temporally distributed rainstorms on watersheds. The model has been applied in several countries with different climatic conditions. TR...

Permeable pavement (PP) is used worldwide to mitigate surface runoff in urban areas. Various studies have examined the factors governing the hydrologic performance of PP. However, relatively little is known about the relative importance of these governing factors and the long-term hydrologic performance of PP. This study applied numerical models—calibrated and validated using existing experimen...

Wet deposition of solutes to an alpine catchment in the southern Sierra Nevada was measured from October 1984 through March 1988. Rainfall had a volume-weighted pH of 4.9, and snowfall had a volume-weighted pH of 5.3. Acetic and formic acids were important components of all wet deposition, contributing 25-30% of the measured anions in snowfall and, through analysis of charge balance deficits, t...

The large quantities of slurry and manure that are produced annually in many areas in which cattle are raised could be an important source of organic matter and nutrients for agriculture. However, the benefits of waste recycling may be partially offset by the risk of water pollution associated with runoff from the fields to which slurry or manure has been applied. In this paper, the effects of ...

climate change is a natural phenomenon that occurs in the long time scale. the most important factors that intensify climate change are changes in reflected radiation from the sun, changes in earth's orbit, greenhouse gases and continents drift. in this research the barandoezchay watershed in west azerbaijan province with an area of 1088 km2 was investigated. due to the lack of synoptic st...

A study was undertaken to determine the predictive capability of Annualized Agricultural NonPoint Source (AnnAGNPS) model with respect to runoff volume, peak flows, and sediment yield from a 130.8 ha watershed in the Siwalik Hills of Nepal. AnnAGNPS simulations are compared with two years of field observations from the study watershed. The model predicted the runoff volume within the range of a...