SOURCE AND LICENCE NOTES

This independent work sample uses Taiwan public datasets. The works rectangle is illustrative. It does not represent a client project or permission to clear vegetation.

1. River-channel snapshot
Water Resources Agency. Source statistical year 2000.
https://data.gov.tw/dataset/25781
Taiwan Open Government Data Licence, version 1.

2. Historical broadleaf-forest snapshot
Forestry and Nature Conservation Agency. Surveys from 2003 to 2009, with partial 2013 updates. Evergreen broadleaf and secondary evergreen broadleaf classes only.
https://data.gov.tw/dataset/9930
The current open-data page links the downloaded resource under the Taiwan Open Government Data Licence, version 1. The archived download also contains older restrictive text. The source record retains this discrepancy. No claim is made that the old text has been legally superseded.

3. Satellite snapshot
Sentinel-2C L2A, 26 September 2026. Original pixel size 10 m.
Contains modified Copernicus Sentinel data (2026).
https://dataspace.copernicus.eu/explore-data/data-collections/sentinel-data/sentinel-2

4. Terrain snapshot
Taiwan official 20 m DTM. 2025 release. Surveys from 2021 to 2022. TWVD2001 elevations. No epoch conversion was applied.
https://data.gov.tw/dataset/176927
Taiwan Open Government Data Licence, version 1.

5. Software
Leaflet 1.9.4, BSD 2-Clause licence.
https://github.com/Leaflet/Leaflet/blob/v1.9.4/LICENSE
Turf 7.2.0, MIT licence.
https://github.com/Turfjs/turf/blob/v7.2.0/LICENSE

METHOD AND LIMITS
The browser calculates a 50 m outward band from river-channel polygons, excluding the channel itself. Turf uses geographic input and spherical area calculations. These values can differ from the EPSG:3826 QGIS reference calculation. Source age, resolution and geometry limitations remain applicable. Re-fetching historical data does not make it a current survey.

The web view is prepared for responsive browser review. Physical phone testing and public hosting have not been completed. Google Earth viewing is represented by the separate static KMZ sample. Automatic refresh, regulatory interpretation and editing in the field are outside this demonstration.