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Bioresource and Agricultural Engineering

Selected Works

Articles 1 - 12 of 12

Full-Text Articles in Civil and Environmental Engineering

A Review Of Pesticide Fate And Transport Simulation At Watershed Level Using Swat: Current Status And Research Concerns, Ruoyu Wang Jun 2019

A Review Of Pesticide Fate And Transport Simulation At Watershed Level Using Swat: Current Status And Research Concerns, Ruoyu Wang

Ruoyu Wang

The application of pesticides in agriculture is a widely-used way to alleviate pest stresses. However, it also introduces various environmental concerns due to the offsite movement of pesticide residues towards receiving water bodies. While the application of process-based modeling approaches can provide quantitative information on pesticide exposure, there are nonetheless growing requirements for model development and improvement to better represent various hydrological and physico-chemical conditions at watershed scale, and for better model integration to address environmental, ecological and economic concerns. The Soil and Water Assessment Tool (SWAT) is an ecohydrological model used in over 3,000 published studies, including about 50 …

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Nitrate Runoff Contributing From The Agriculturally Intensive San Joaquin River Watershed To Bay-Delta In California, Ruoyu Wang May 2019

Nitrate Runoff Contributing From The Agriculturally Intensive San Joaquin River Watershed To Bay-Delta In California, Ruoyu Wang

Ruoyu Wang

Nitrogen loading from agricultural landscapes can trigger a cascade of detrimental e#11;ects on
aquatic ecosystems. Recently, the spread of aquatic weed infestations (Eichhornia crassipes, Egeria densa,
Ludwigia spp., and Onagraceae) in the Sacramento-San Joaquin Delta of northern California has raised
concerns, and nitrogen loading from California’s intensive farming regions is considered as one of
the major contributors. In this study, we employed the Soil andWater Assessment Tool (SWAT) to
simulate nitrogen exports from the agriculturally intensive San Joaquin River watershed to the Delta.
The alternate tile drainage routine in SWAT was tested against monitoring data in the tile-drained area
of …

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Environmental Fate And Impact Assessment Of Thiobencarb Application In California Rice Fields Using Ricewq, Ruoyu Wang May 2019

Environmental Fate And Impact Assessment Of Thiobencarb Application In California Rice Fields Using Ricewq, Ruoyu Wang

Ruoyu Wang

Thiobencarb is a commonly used herbicide in Northern California rice fields. Released paddy water containing thiobencarb may pose ecological risks to non-targeted organisms. In this research, the Rice Water Quality Model (RICEWQ) is  equilibrium tested and then calibrated using monitoring data at field level. Then it is employed to assess the environmental fate and impacts of thiobencarb in the Colusa Basin, and the effects of different management practices on water use and thiobencarb exposures. The model predicted thiobencarb concentrations from rice fields for multiple years throughout the Basin, using input from California Pesticide Use Reporting (PUR) database, and assessed both the …

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Evaluation Of Select Sensors For Real-Time Monitoring Of Escherichia Coli In Water Distribution Systems, Syreeta L. Miles, Ryan G. Sinclair, Mark R. Riley, Ian L. Pepper Apr 2019

Evaluation Of Select Sensors For Real-Time Monitoring Of Escherichia Coli In Water Distribution Systems, Syreeta L. Miles, Ryan G. Sinclair, Mark R. Riley, Ian L. Pepper

Ryan Sinclair PhD, MPH

This study evaluated real-time sensing of Escherichia coli as a microbial contaminant in water distribution systems. Most sensors responded to increased E. coli concentrations, showing that select sensors can detect microbial water quality changes and be utilized as part of a contaminant warning system.

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Modeling Pesticide Fate And Transport At Watershed Scale Using The Soil & Water Assessment Tool: General Applications And Mitigation Strategies, Ruoyu Wang Mar 2019

Modeling Pesticide Fate And Transport At Watershed Scale Using The Soil & Water Assessment Tool: General Applications And Mitigation Strategies, Ruoyu Wang

Ruoyu Wang

Pesticide residue runoff to surface water is of great concern to local stakeholders who seek to preserve or achieve good water quality. The Soil & Water Assessment Tool (SWAT) has been widely used to assess many environmental problems related to water resources and nonpoint-source pollution, including sediment and nutrient loads and pesticides. However, a comprehensive review of existing studies on SWAT-based pesticide modeling is still not available in the literature. Therefore, in this chapter, we present an overview summarizing all previous SWAT applications in studying the fate and transport of pesticides around the world, based on the peer-reviewed literature. We …

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Integrating Multimedia Models To Assess Nitrogen Losses From The Mississippi River Basin To The Gulf Of Mexico, Ruoyu Wang Nov 2018

Integrating Multimedia Models To Assess Nitrogen Losses From The Mississippi River Basin To The Gulf Of Mexico, Ruoyu Wang

Ruoyu Wang

This study describes and implements an integrated, multimedia, process-based system-level approach to estimating nitrogen (N) fate and transport in large river basins. The modeling system includes the following components: (1) Community Multiscale Air Quality (CMAQ), (2) Weather Research and Forecasting Model (WRF), (3) Environmental Policy Integrated Climate (EPIC), and (4) Soil and Water Assessment Tool (SWAT). The previously developed Fertilizer Emission Scenario Tool for CMAQ (FEST-C), an advanced user interface, integrated EPIC with the WRF model and CMAQ. The FEST-C system, driven by process-based WRF weather simulations, includes atmospheric N additions to agricultural cropland and agricultural cropland contributions to ammonia emissions. This study focuses …

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Input Uncertainty On Watershed Modeling: Evaluation Of Precipitation And Air Temperature Data By Latent Variables Using Swat, Ruoyu Wang Oct 2018

Input Uncertainty On Watershed Modeling: Evaluation Of Precipitation And Air Temperature Data By Latent Variables Using Swat, Ruoyu Wang

Ruoyu Wang

Latent variables (i.e., normally distributed random noise) provide valuable information regarding model input uncertainty. Watershed processes have been explored with sophisticated simulation models in the past few decades and researchers have found that incorporating the uncertainty attributed to forcing inputs, model parameters, and measured data, can help improve simulation results, however, not in all cases. Latent variable use requires careful consideration to determine if results are better or worse. In this study, latent variables were implemented to both precipitation and air temperature data to investigate the influence on model predictions and associated predictive uncertainty by using the Soil and Water …

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Predication Of The Sources Of Particulate Polycyclic Aromatic Hydrocarbons In China With Distinctive Characteristics Based On Multivariate Analysis, Ruoyu Wang May 2018

Predication Of The Sources Of Particulate Polycyclic Aromatic Hydrocarbons In China With Distinctive Characteristics Based On Multivariate Analysis, Ruoyu Wang

Ruoyu Wang

Particulate polycyclic aromatic hydrocarbons (PAHs) have the characteristics of high carcinogenicity, degradation resistance, and long-distance transport. It is necessary to determine the critical sources that contribute to PAHs in atmospheric particulatematter (PM), soils, and sediments. In the present study, particulate PAHs were collected from Chinese cooking, biomass combustion, waste incineration, coal combustion, and petroleum combustion in different regions of the Chinese mainland. Through linear regression analysis, the relationships have been investigated between different measurement units, including the mass of particulate PAHs per mass of particle matter, mass of particulate PAHs per volume of …

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Ultrasonic Enhanced Liquefaction And Saccharification Of Corn For Bio-Fuel Production, Samir Kumar Khanal, Melissa T. Montalbo, Johannes Van Leeuwen, Gowrishankar Srinivasan, David A. Grewell Sep 2015

Ultrasonic Enhanced Liquefaction And Saccharification Of Corn For Bio-Fuel Production, Samir Kumar Khanal, Melissa T. Montalbo, Johannes Van Leeuwen, Gowrishankar Srinivasan, David A. Grewell

Gowrishankar Srinivasan

Dry grind corn milling does not reach full efficiency of starch conversion to sugars and subsequently to ethanol because of limitations in the milling process. This paper examines the use of high-power ultrasonics to enhance the release of fermentable sugars from milled dry corn. In this work, 20 kHz ultrasonic energy was used to pretreat corn mash prior to enzymatic conversion of corn starch to glucose in a batch-mode. The ultrasonic amplitude was varied from 0, 191 to 320 µm pp . The corn mash was sonicated for 0 (control), 20 and 40 seconds. Other experimental variables that were studied …

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Investigations And Management Of Epizootic Plague At Ice House Reservoir, Eldorado National Forest, California, 1994 And 1995, Kenneth R. Townzen, Malcolm A. Thompson, Charles R. Smith Jun 2015

Investigations And Management Of Epizootic Plague At Ice House Reservoir, Eldorado National Forest, California, 1994 And 1995, Kenneth R. Townzen, Malcolm A. Thompson, Charles R. Smith

Charles Kay Smith

The occurrence of plague (Yersinia pestic) at Ice House Reservoir in 1994 and 1995 was characteristic of widespread epizootics in high use recreational areas of California. Staff of the Vector-Borne Disease Section investigated these epizootics and found dense populations of plague susceptible California ground squirrels (Spermophilus beecheyi) with high numbers of fleas, primarily Diamanus montanus, the most important plague vector. This combination indicated a high risk of plague exposure to campground users. A non-fatal human case of plague, contracted at Mountain Camp II, was reported after the initial epizootic investigation. The patient's exposure occurred prior to the reporting of the …

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Ultrasonic Enhanced Liquefaction And Saccharification Of Corn For Bio-Fuel Production, Samir Kumar Khanal, Melissa T. Montalbo, Johannes Van Leeuwen, Gowrishankar Srinivasan, David A. Grewell May 2015

Ultrasonic Enhanced Liquefaction And Saccharification Of Corn For Bio-Fuel Production, Samir Kumar Khanal, Melissa T. Montalbo, Johannes Van Leeuwen, Gowrishankar Srinivasan, David A. Grewell

Gowrishankar Srinivasan

Dry grind corn milling does not reach full efficiency of starch conversion to sugars and subsequently to ethanol because of limitations in the milling process. This paper examines the use of high-power ultrasonics to enhance the release of fermentable sugars from milled dry corn. In this work, 20 kHz ultrasonic energy was used to pretreat corn mash prior to enzymatic conversion of corn starch to glucose in a batch-mode. The ultrasonic amplitude was varied from 0, 191 to 320 µm pp . The corn mash was sonicated for 0 (control), 20 and 40 seconds. Other experimental variables that were studied …

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Applications Of Homotopy Perturbation Transform Method For Solving Time-Dependent Functional Differential Equations, Habibolla Latifizadeh Dec 2010

Applications Of Homotopy Perturbation Transform Method For Solving Time-Dependent Functional Differential Equations, Habibolla Latifizadeh

H. L. Zadeh

No abstract provided.

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