Analysis of water and nitrogen mass balance by intensive field measurement on a tropical paddy field | |
| Author | Jaruwan Tantasut |
| Call Number | AIT Thesis no. WM-00-21 |
| Subject(s) | Water--Analysis Water--Nitrogen content |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Abstract | Nitrogen mass balances in a 1600 m 2 experimental field in Asian Institute of Technology, Thailand were estimated to determine the pathways of nitrogen in the experimental field. The amount of nitrogen in terms of nitrate nitrogen, ammonia nitrogen, organic nitrogen and total nitrogen entering and leaving the experimental field were measured. Inputs of total nitrogen to the field by fertilizer, irrigation water and precipitation were 132.25, 24.99 and 10.48 kg/ha, respectively. Outputs of total nitrogen from the field by leaching to groundwater and uptake in harvested crops were 42.35 and 103 kg/ha, respectively. The amounts of nitrogen stored in pre-cultivation and post-cultivation soil of 1 m depth were 1925.61and1868.41 kg, respectively. Nitrogen mass balance was evaluated in terms of total nitrogen (T-N) for the whole cultivation period. Input nitrogen to the experimental field was 167. 72 kg/ha. Output nitrogen from the experimental field was 145.35 kg/ha and the difference of nitrogen stored in precultivation and post-cultivation soil was 57.2 kg. From the balancing the amount of nitrogen, 34.65 kg of nitrogen lost from the experimental field. Basically, the amount of nitrogen leaving the field that was not taken up in harvested crops or leached to groundwater was loss by volatilization and denitrification. The amount of nitrogen contained in seeds before cultivation was 2.55 kg/ha and the amount of nitrogen contained in harvest crops was 105.5 kg/ha. In harvested crops, high amount of nitrogen was contained in grains (63 kg/ha), while amount of nitrogen contained in stems, leaves and roots were 17.6, 19.0 and 5.91 kg/ha, respectively. The difference in amount of nitrogen in pre-cultivation and post-cultivation soil showed 18% increase of nitrate nitrogen and 5.02% increase of organic nitrogen while 25.3% of ammonia nitrogen decreased. It can be said that ammonia nitrogen changed to nitrate nitrogen and organic nitrogen. |
| Year | 2001 |
| 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) | Iida, Toshiaki |
| Examination Committee(s) | Izumi, Norihiro ;Clemente, Roberto S. ;Babel, Mukand S. |
| Scholarship Donor(s) | The German Academic Exchange Service (DAAD) |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 2001 |