12:00 PM - 12:15 PM
[HTT29-12] Development of trophic state index monitoring method in the lakes using Landsat-8 data
Keywords:satellite, Landsat, eutrophication, lake, monitoring
So the method by which automatic calculation and mapping of TSI using Landsat-8/OLI data with sensitive (12bit) and the high spatial resolution (30m) launched in February, 2013 was developed by this research. Lake Shinji and Lake Nakaumi (Shimane and Tottori prefectures in Japan) as test sites, were chosen. The 15 scenes from April, 2013 to July, 2014 were used for satellite data. At first, LCI (Linear Combination Index) method (Frouin et al., 2007) known as a simple atmospheric correction algorithm for ocean color sensor was used for Chl.a estimation from OLI data easily. The OLI band 2 , band 3. and band 5 were selected as the bands of LCI method. The -1 and 0.3 were set as the Angstrom index which indicates wavelength-dependence of aerosol. On the other hand, M-TSI was calculated from a relationship between Chl.a, TN, and TP in our country made separately. After the simple Rayleigh scattering correction was conducted, a target area was extracted from header information on Landsat-8 data using the programming function of the Matlab software (MathWorks Inc.). Finally, the automatic mapping system that TSI is estimated via Chl-a from LCI was developed. The characteristic of TSI distribution indicates the very high value in the western part of Lake Shinji in particular.