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Temporal variation of TFs area with CI error (ha)
| Year_Range | KPT_Area | KPT_CI_Error | Year_Range | Yangma_Area | Yangma_CI_Error |
|---|---|---|---|---|---|
| 1984–1986 | – | – | 1984–1986 | 972.04 | 45.39 |
| 1986–1988 | 1678.81 | 78.4 | 1887–1989 | 517.06 | 24.15 |
| 1989–1991 | 1651.07 | 77.1 | 1990–1992 | 450.83 | 21.05 |
| 1992–1994 | 1226.50 | 57.28 | 1993–1995 | 415.44 | 19.4 |
| 1995–1997 | 1146.25 | 53.53 | 1996–1998 | 383.23 | 17.9 |
| 1998–2000 | 1136.97 | 53.1 | 1999–2001 | 308.74 | 14.42 |
| 2001–2003 | 947.26 | 44.24 | 2002–2004 | 308.90 | 14.43 |
| 2004–2007 | – | – | 2005–2007 | 372.53 | 17.4 |
| 2008–2010 | 1338.51 | 62.51 | 2008–2010 | 351.64 | 16.42 |
| 2011–2012 | – | – | 2011–2012 | – | – |
| 2013–2015 | 1344.84 | 62.8 | 2013–2015 | 298.04 | 13.92 |
| 2016–2018 | 1396.80 | 65.23 | 2016–2018 | 299.01 | 13.96 |
| 2019–2021 | 1394.76 | 65.14 | 2019–2021 | 258.25 | 12.06 |
| 2022–2024 | 1408.17 | 65.76 | 2022–2024 | 290.12 | 13.55 |
Formulas of the spectral indices used in this study
Confusion matrix of TF validation
| Class | TF | Non-TF | Total | UA | |
|---|---|---|---|---|---|
| Map pixels | TF | 234 | 16 | 250 | 93.6% |
| Non-TF | 10 | 199 | 209 | 95.2% | |
| Total | 244 | 215 | 459 | OA = 94.3% | |
| PA | 96.0% | 92.6% | Kappa = 0.88 |
Annual TF area with 95% CIs (2017–2024)
| Year | KPT area | KPT CI error | Yangma area | Yangma CI error |
|---|---|---|---|---|
| 2017 | 1492.23 | 69.69 | 291.93 | 13.63 |
| 2018 | 1624.92 | 75.88 | 299.48 | 13.99 |
| 2019 | 1605.06 | 74.96 | 401.01 | 18.73 |
| 2020 | 1227.01 | 57.3 | 438.34 | 20.47 |
| 2021 | 1489.75 | 69.57 | 232.22 | 10.84 |
| 2022 | 1498.94 | 70.0 | 351.32 | 16.41 |
| 2023 | 1236.24 | 57.73 | 278.8 | 13.02 |
| 2024 | 1492.28 | 69.69 | 290.91 | 13.59 |