Vulnerability assessment to delineate areas that are more susceptible to contamination from anthropogenic sources has become an important element for sensible resource management and land use planning. This contribution aims at estimating aquifer vulnerability by applying the DRASTIC model as well as utilizing sensitivity analyses to evaluate the relative importance of the model parameters for ...

Despite improvements in the use of soil conservation practices, crop rotation and nutrient management programs, significant concern still exists regarding soil erosion and nutrient losses in runoff from row crop production. In the US, states are required to implement water quality standards based on USEPA guidelines or other scientifically defensible methods (Ice and Binkley, 2003). Agroforestr...

Subgrade moisture content varies with environmental and soil conditions and has significant influence on pavement performance. Therefore, it is important to establish realistic estimates of expected subgrade moisture contents to account for the effects of this variable on predicted pavement performance during the design stage properly. The initial boundary soil suction profile for a given pavem...

Due to the complex nature of pesticide transport, process-based models can be difficult to use. For example, pesticide transport can be effected by macropore flow, and can be further complicated by sorption, desorption and degradation occurring at different rates in different soil compartments. We have used the Root Zone Water Quality Model (RZWQM) to investigate these phenomena with field data...

An Analysis on Soil Properties on Predicting Critical Hydraulic Gradients for Piping Progression in Sandy Soils By Tammy Jacobson, Master of Science Utah State University 2013 Major Professor: Dr. John Rice Department: Civil and Environmental Engineering Piping is a form of internal erosion in which soil particles are eroded at a seepage exit location due to the forces imposed on the particles ...

Permeability is a very important engineering property of soils and finds utility in a number of soil engineering problems such as yield of wells and seepage through and below the earth structures. It controls the hydraulic stability of soil masses. The permeability of soils is also required in the design of filters required to prevent piping in hydraulic structures. However, the determination o...

Accurate knowledge of water fluxes in the vadose zone of watersheds is important for applications such as water resources management and climate forecasting. Most, if not all, large-scale studies follow a pragmatic approach where simplifying assumptions have to be made regarding problem formulation and estimation of hydraulic properties. This study investigates simplifications in both regards t...

Woody plants native to mesic habitats tend to be more vulnerable to drought-induced cavitation than those in xeric habitats. Cavitation resistance in herbaceous plants, however, is rarely studied and whether or not annual plants in arid habitats conform to the trends observed in woody plants is unknown. This question is addressed by comparing the hydraulic properties of annual plants endemic to...