Red tide monitoring method in coastal waters of Hebei Province based on decision tree classification
, , , and | Jun 24, 2022
About this article
Published Online: Jun 24, 2022
Page range: 43 - 60
Received: Oct 29, 2021
Accepted: May 15, 2022
DOI: https://doi.org/10.2478/amns.2022.1.00051
Keywords
© 2022 Kang Yan et al., published by Sciendo
This work is licensed under the Creative Commons Attribution 4.0 International License.
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Red tide area extracted by various methods
| Red tide monitoring method | Red tide area |
|---|---|
| Chlorophyll method | 1,548 km2 |
| Single band ratio method | 2,780 km2 |
| Multi-band difference ratio method | 1,866 km2 |
| Decision tree classification | 1,943 km2 |
Sample calculation results
| Sample point | Land | Abnormal water area | Clean water area | |||
|---|---|---|---|---|---|---|
| A | R | A | R | A | R | |
| 1 | –0.490186 | 0.431966 | 0.208190 | 0.520284 | 0.157197 | 0.343478 |
| 2 | –0.515848 | 0.436719 | 0.197401 | 0.511940 | 0.224858 | 0.336290 |
| 3 | –0.488859 | 0.328717 | 0.195482 | 0.518240 | 0.179280 | 0.350442 |
| 4 | –0.456237 | 0.349821 | 0.176524 | 0.524408 | 0.245110 | 0.403250 |
| 5 | –0.341247 | 0.420170 | 0.167894 | 0.473622 | 0.159053 | 0.331198 |
| 6 | –0.451948 | 0.454620 | 0.180254 | 0.535965 | 0.376934 | 0.249489 |
| 7 | –0.392420 | 0.459112 | 0.189532 | 0.505973 | 0.342486 | 0.267309 |
| 8 | –0.398071 | 0.518295 | 0.197775 | 0.519787 | 0.318415 | 0.143954 |
| 9 | –0.477858 | 0.515863 | 0.218227 | 0.510321 | 0.230179 | 0.421184 |
| 10 | –0.502500 | 0.504848 | 0.183310 | 0.522109 | 0.248343 | 0.393807 |
| 11 | –0.502628 | 0.430932 | 0.172382 | 0.467220 | 0.141973 | 0.334235 |
| 12 | –0.461805 | 0.554743 | 0.169851 | 0.525808 | 0.149018 | 0.372128 |