Modeling Floodplain Filtration for the Improvement of River Water Quality

Abstract. A mathematical model was developed to describe a treatment method of floodplain filtration for the improvement of river water quality. The process consists of spraying poor quality river water onto the river floodplains and thus allowing soil filtration to treat water before it gets back again into the main river stream. This technique can be readily employed in Korea because it exploits the characteristics of the climate and rivers in the country, as described in an experimental study o

Examination of the design procedures for drainage/subirrigation systems in the lower Fraser Valley, British Columbia

Techniques for designing drainage/subirrigation systems in the Lower Fraser Valley of British Columbia are examined in the present study. An attempt was made to formally define the overall goal in the design of such systems. Various difficulties were encountered in proceeding formally in the design. Therefore, a "branch and bound" approach was used in which a series of studies are conducted to focus our attention on the key issues of the problem and to regroup or eliminate other issues of secondary importance. A simple study showed that drainage designs seemed to be the limiting factors in drainage/subirrigation system designs for the Lower Fraser Valley. Therefore, subirrigation design was not considered in further analyses. The drainage requirements for different seasons were discussed. It was suggested that a drainage system designed to meet workability requirements in early spring should be more than sufficient to meet other seasonal requirements of interest from a drainage point of view. It was suggested that these requirements will be met by designing a drainage system that ensures at least one workable period of twelve days in March. A Markov chain model was proposed that can simulate the transitions in the water table elevations in response to weather. Design curves were presented for some local soils that can aid designers to perform drainage designs that satisfy requirements of the individual farmers. A study was undertaken to investigate the importance of uncertainty in soil parameters on the drainage system design. First and second order methods of analyzing uncertainty were applied to Hooghoudt's equation of designing drainage systems. The applicability of the uncertainty approach was extended to the numerical model of designing drainage systems based on the Boussinesq equation. An example problem was solved to illustrate how a drainage design criterion can be formulated when uncertainties due to both the climate and the soil parameters are present at the same time. Conclusions were drawn from the present study and recommendations were made for future work. The environmental impacts of agricultural drainage were discussed. They are included in the appendix because the main thrust of the thesis was on the design of drainage/subirrigation systems. Also, a design methodology was proposed in the appendix that can be used in designing drainage systems on a steady state basis in the absence of any knowledge about the saturated hydraulic conductivity of the soil or the location of the impermeable layer.Graduate and Postdoctoral StudiesGraduat

Evaluation of Frying Oil Quality Using VIS/NIR Hyperspectral Analysis

Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 7 (2005): Evaluation of Frying Oil Quality Using VIS/NIR Hyperspectral Analysis by Samira Kazemi, Ning Wang, Michael Ngadi, Shiv O. Prashe

Correction: Niazi, A., Prasher, S.O., Adamowski, J., Gleeson, T. A System Dynamics Model to Conserve Arid Region Water Resources through Aquifer Storage and Recovery in Conjunction with a Dam. Water 2014, 6, 2300–2321

We have recently been made aware by Prof. Sharon Megdal (The University of Arizona) and Dr. Peter Dillon (CSIRO) of some errors and omissions in our recent paper [1]. The authors wish to make the following corrections to this paper:[...

Evaluating Three Hydrological Distributed Watershed Models: MIKE-SHE, APEX, SWAT

Selecting the right model to simulate a specific watershed has always been a challenge, and field testing of watersheds could help researchers to use the proper model for their purposes. The performance of three popular Geographic Information System (GIS)-based watershed simulation models (European Hydrological System Model (MIKE SHE), Agricultural Policy/Environmental Extender (APEX) and Soil and Water Assessment Tool (SWAT)) were evaluated for their ability to simulate the hydrology of the 52.6 km2 Canagagigue Watershed located in the Grand River Basin in southern Ontario, Canada. All three models were calibrated for a four-year period and then validated using an independent four-year period by comparing simulated and observed daily, monthly and annual streamflow. The simulated flows generated by the three models are quite similar and closely match the observed flow, particularly for the calibration results. The mean daily/monthly flow at the outlet of the Canagagigue Watershed simulated by MIKE SHE was more accurate than that simulated by either the SWAT or the APEX model, during both the calibration and validation periods. Moreover, for the validation period, MIKE SHE predicted the overall variation of streamflow slightly better than either SWAT or APEX

Monitoring corn and soybean agroecosystems after establishing no-tillage practices in Québec, Canada

, H. 2007. Monitoring corn and soybean agroecosystems after establishing no-tillage practices in Québec, Canada. Can. J. Plant Sci. 87: 841-849. The conversion to no-tillage (NT) may seem risky to some producers who rely on tillage to control weeds, some insect pests and disease-causing pathogens that can reduce crop yield. Weeds, arthropods, and disease incidence were monitored in silage corn (Zea mays L.) and soybean (Glycine max L. Merr.) agroecosystems with CT and newly established NT plots in Ste-Anne-de-Bellevue, Québec. During the first 2 establishment years, there were more annual grass and fewer annual broadleaf weeds in NT than in CT plots, but the surface area covered by weeds (broadleaf, grasses and perennials) was greater in CT than NT plots. Foliar arthropods were more numerous in soybean than corn plots in both years, but were unaffected by tillage. There were more ground-dwelling generalist predators, especially Coleoptera and Carabidae, in CT than NT plots, while spiders and harvestmen (Araneae and Opiliones) were dominant in NT plots. Crop damage from insect pests and diseases was below economic thresholds, but 5 yr of yield monitoring (2000)(2001)(2002)(2003)(2004) revealed a trend of greater silage corn and soybean yields in CT than NT plots. The reduction in crop yield after establishing NT practices at this site was probably due to rooting constraints from inadequate seedbed preparation in the NT system, rather than from weed competition, insect damage or crop diseases. Key words: Arthropods, crop disease, silage corn, soybean, tillage, weed control Whalen, J. K., Prasher, S. O. et Benslim, H. 2007. Surveillance aux agro-écosystèmes de maïs-ensilage et de soya convertis en semis-direct au Québec, Canada. Can. J. Plant Sci. 87: 841-849. Le système de semis-direct (NT) peut sembler risqué pour quelques producteurs qui comptent sur le labourage pour contrôler les mauvaises herbes, quelques insectes ravageurs et les pathogènes causant des maladies qui peuvent réduire la production végétale. Nous avons examiné des mauvaises herbes, des arthropodes, et l'incidence des maladies dans les agro-écosystèmes de maïs-ensilage (Zea mays L.) et soya (Glycine max L. Merr.), aux parcelles nouvellement converties en NT à Sainte-Anne-de-Bellevue, Québec. Pendant les deux premières années d'étab-lissement, il y avait plus des mauvaises herbes annuelles et moins des dicotylédones annuelles avec NT que dans les parcelles avec CT, mais le degré d'envahissement par les mauvaises herbes était plus grand dans le CT que le NT. Pendant deux ans, les arthropodes foliaires étaient plus nombreux en soya par apport au maïs-ensilage, mais ils n'étaient pas affectés par le labourage du sol. Il y avait plus de prédateurs de généraliste, particulièrement les coléoptères et les Carabidae, dans le CT que le NT, alors que les araignées et les faucheux (Araneae et Opiliones) étaient dominants dans les parcelles sous NT. La diminution du rendement de la récolte après l'établissement du NT sur ce site a été probablement due à la difficulté d'enracinement plutôt causée par une prépa-ration inadéquate du semis avec la pratique NT que par la concurrence des mauvaises herbes, des dommages d'insecte ou des maladies végétales

A System Dynamics Model to Conserve Arid Region Water Resources through Aquifer Storage and Recovery in Conjunction with a Dam

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Evaluation of the MIKE SHE Model in a Cold Region

Given its rapid urbanization, the Canagagigue Creek watershed, located in Grand River Basin (Ontario, Canada), is subjected to shifting hydrological patterns. Consequently, surface runoff was simulated using a watershed-scale model MIKE SHE. The model was calibrated with four years of data and validated with another four years data. Satisfactory levels of overall correlation (R2) between monitored and model-simulated monthly runoff were: 0.87 and 0.77 for the calibration and validation periods, respectively. Corresponding values of the Nash-Sutcliffe coefficient, 0.86 and 0.75, were similar. The model was also used to simulate different management scenarios, urbanization, deforestation, conversion of pastureland into agriculture, diversification of corn system into cash crops, and application of tile drainage. Urbanization showed little impact on surface runoff as increase in urbanized area was a small fraction of the watershed area. Deforestation considerably increased (11%) the total flow. Change in cropping patterns and installation of drainage system had marginal impacts on the surface runoffs. Overall, the model was able to simulate surface runoff reasonably well on monthly and annual basis, although slightly poorer on daily basis. It was concluded that the model could be used to investigate hydrological behaviour of the watersheds in cold climate