Assessing pesticides leaching potential in layered soils : a case study in Northeast Region of Thailand | |
| Author | Doungpond Ponggumnerd |
| Call Number | AIT Thesis no.WM-21-01 |
| Subject(s) | Pesticides--Environmental aspects--Thailand--Northeast Region Soils--Thailand--Northeast Region--Thailand--Northeast Region Agricultural chemicals--Environmental aspects |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Water Engineering and Management |
| Publisher | Asian Institute of Technology |
| Abstract | The present study aims to develop a leaching potential model to assess the relative leaching potential of widely used top five pesticides for paddy fields in Northeast Thailand based on the revised attenuation factor (AFR) and mass fraction (MF) in layered soils. Therefore, the Python is used for scripting the assessment of AFR and MF models to compare with a point-based HYDRUS-1D solute transport to get the accuracy of the suitable models for the leaching potential vulnerability together with the geographical information system (GIS). Additionally, the results in this study are conducted during 2010-2019 of the recharge rates from HYDRUS-1D program, and there are seasonal paddy fields periods. Moreover, the assessment represents the classification to consider a decision making on environment and human health from pesticides contamination, and it is useful for many aspects of water management. The simulation of a point-based solute transport from HYDRUS-1D at the 4 selected site locations shows that the ten chemicals can be ranked, which the highest ranked is Paraquat from Nongkai and Surin, and Dicamba from Mukdahan and Chaiyaphum, respectively, and the lowest ranked is Propineb for all 4 weather stations. Furthermore, the accuracy of the models using the revised attenuation factor (AFR) and mass fraction (MF) in layered soils reveals that the comparison of the relative leaching orders of chemicals between MF models with HYDRUS-1D is higher than the comparison between AF models with HYDRUS-1D. Moreover, the results show that there is a contouring map from high to low in the northeast to the southwest, respectively which can be concluded that the recharge rate is different within the northeast Thailand map, and the differences of the soil characteristics likewise. Thus, the leaching potential class changes corresponding to locations which depend on recharge rate, and the soils. The results also indicated that the pesticides leaching risk can be ranked from highest to lowest by the groundwater vulnerability map which are Paraquat, Chlorpyrifos, Glyphosate, 2,4-D and Propineb, respectively. |
| Year | 2021 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Water Engineering and Management (WM) |
| Chairperson(s) | Shanmugam, Mohana Sundaram |
| Examination Committee(s) | Shrestha, Sangam;Babel, Mukand Singh;Sarawut Ninsawat |
| Scholarship Donor(s) | Royal Thai Government Fellowship |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 2021 |