| Author | Suwisa Mahasandana |
| Call Number | AIT Diss. no.RS-09-03 |
| Subject(s) | Water quality--Remote-sensing images--Bangpakong Estuary (Thailand)
|
| Note | A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Engineering in Remote Sensing and Geographic Information Systems |
| Publisher | Asian Institute of Technology |
| Series Statement | Dissertation ; no. RS-09-03 |
| Abstract | Satellite Imagery has limited using in water monitoring. Chlorophyll-a(chl-a), turbidity and temperature in ocean can be approximately estimated by using remote sensing methodology. The accuracy of chl-a estimation may be improved by the determination of suitable radiance bands and algorithms. The aim of a present study was to investigate in suitability of a combination of radiance bands to effectively determine chl-a concentration in marine waters of the gulf of Thailand. Suitable indices were established by using chl-a high absorption and high reflectance wavelengths to produce indices. The relationship between indices and chl-a are determined and then applied satellite bands for model development. The minor focuses of this study were to measure turbidity in coastal waters by Landsat 5 satellite imagery and to produce the correlation models between water quality parameters and turbidity. The water quality–turbidity correlation model could be the indirect monitored models for satellite application. Sea surface spectrum was measured in situ using a portable spectrometer. Chl-a concentration and all chemical parameters were analyzed in the laboratory. Satellite images were obtained from Landsat 5 for the sampling day. The results of a three band index from the spectrometer composed of wavelengths of 435, 488 and 692 nm indicate the most significant correlation with chl-a concentration. The exponential relation was observed with a highest coefficient correlation of r2 =0.83. The index model was applied to Landsat 5 data. Observed chl-a dataset was compared to that estimated from Landsat 5. This analysis offered high correlation of 0.73. The spectral index models for chl-a estimation and methodology can be applied to any other coastal area. For this study, the best correlation between turbidity and Landsat 5 satellite received from the model of band 2 and turbidity by r2 of 0.88. Turbidity was found the correlation to suspended solid, biomass, dissolved oxygen, transparency, phosphate and total nitrogen with the r2 of 0.97, 0.92, 0.48, 0.83, 0.73 and 0.56, respectively. These correlations were applied to the turbidity-Landsat 5 model. The results were the water quality maps from satellite imagery. The methodology can be applied to any other coastal area. |
| Year | 2009 |
| Corresponding Series Added Entry | Asian Institute of Technology. Dissertation ; no. RS-09-03 |
| Type | Dissertation |
| School | School of Engineering and Technology (SET) |
| Department | Department of Information and Communications Technologies (DICT) |
| Academic Program/FoS | Remote Sensing (RS) |
| Chairperson(s) | Tripathi, Nitin Kumar |
| Examination Committee(s) | Honda, Kiyoshi ;Preeda Parkpian ;Thaithaworn Lirdwitayaprasit |
| Scholarship Donor(s) | Mahidol University, Thailand |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 2009 |