abstract microbial contaminants transport to groundwater is a serious environmental problem that can result in large outbreaks of waterborne diseases. some of bacteria can travel from vadose zone and cause contamination of groundwater resources. thus, an accurate prediction of transport and fate of pathogenic microorganisms in unsaturated soil is needed to protect groundwater resources. the mai...

[1] In this study we estimate a time series of regional groundwater anomalies by combining terrestrial water storage estimates from the Gravity Recovery and Climate Experiment (GRACE) satellite mission with in situ soil moisture observations from the Oklahoma Mesonet. Using supplementary data from the Department of Energy’s Atmospheric Radiation Measurement (DOE ARM) network, we develop an empi...

Understanding of hydrological processes, including consideration of interactions between vegetation growth and water transfer in the root zone, underpins efficient use of water resources in arid-zone agriculture. Water transfers take place in the soil-plant-atmosphere continuum, and include groundwater dynamics, unsaturated zone flow, evaporation/transpiration from vegetated/ bare soil and surf...

An analytical one-dimensional model for vertical transmission of barometric pressure in soil unsaturated zone has been developed to examine the effect of free boundary caused by water table. The model is applicable to a special case in which the water table moves in according to the pressure with high barometric efficiency. Ambient sinusoidal pressure fluctuation is assumed at the soil surface....

Rainfall infiltration exerts great effect on the stability of soil slopes. Based on the actual rainfall data, saturated-unsaturated seepage theory and the mechanical theory of unsaturated porous media, numerical simulations were conducted to examine the seepage field of saturatedunsaturated slope during rainfall infiltration in this paper. The influence of the coefficient with rainfall duration...

Hydrological modeling of the unsaturated soil zone fluxes allows the transfer processes simulation through the hydrological active soil zone. The pedotransfer functions (FTP) are useful tools in the modeling process. They contain analytical functions derived through statistic optimization process using a large amount of soil information data. This paper aims to analyze the level of reliability ...

Upon an increase of moisture, unsaturated soil may collapse or swell, depending on the loading state and history. This important characteristic must be realistically reproduced by a constitutive model aimed for practical applications. In addition to collapse/swelling, other essential features, such as deformation and failure following arbitrary shearing paths, must also be realistically reprodu...

Prediction method for undrained shear behaviour of unsaturated soils is discussed in this paper. Based on Original Cam Clay model, authors have proposed constitutive model for unsaturated soils that the effect of water content is incorporated into superloading surface concept. Firstly, stress path of constant volume shear test is formulated under constant void ratio condition. And relationship ...

Pesticide transport through the unsaturated zone is a function of chemical and soil characteristics, application, and water recharge rate. The fate and transport of 82 pesticides and degradates were investigated at five different agricultural sites. Atrazine and metolachlor, as well as several of the degradates of atrazine, metolachlor, acetochlor, and alachlor, were frequently detected in soil...

Considering unsaturation conditions of soil significantly helps to produce relatively real results. Numerical methods have been assumed as conventional methods in soil mechanics to examine soil behavior. However, the accuracy of numerical methods dramatically depends on applying the appropriate behavioral model to solve problems. One of the known elastoplastic models for unsaturated soils i...