Summary of results from GIS analysis of historical Landsat imagery, 1973–2013 (see Figure 1 for locations, Table S1 for detailed measurements within each study grid). DOI: https://doi.org/10.1525/elementa.263.t1
| . | Poldered Areas . | Natural Areas . | ||||
|---|---|---|---|---|---|---|
| Year | 1973* | 2003 | 2013 | 1973* | 2003 | 2013 |
| Length of tidal channels outside of polders (km) | 1891 | 783 | 782 | 1964 | 1987 | 1981 |
| Length of tidal channels obstructed by polders [1° creeks] (km) | 0 | 1108 | 1108 | 0 | 0 | 0 |
| Length of tidal channels outside of polders with >50% obstruction [khas land] (km) | 0 | 355 | 420 | 0 | 0 | 0 |
| % change in drainage network | –59% | 1% | ||||
| % of conduit channels converted to khas land | 45% | 54% | 0% | |||
| . | Poldered Areas . | Natural Areas . | ||||
|---|---|---|---|---|---|---|
| Year | 1973* | 2003 | 2013 | 1973* | 2003 | 2013 |
| Length of tidal channels outside of polders (km) | 1891 | 783 | 782 | 1964 | 1987 | 1981 |
| Length of tidal channels obstructed by polders [1° creeks] (km) | 0 | 1108 | 1108 | 0 | 0 | 0 |
| Length of tidal channels outside of polders with >50% obstruction [khas land] (km) | 0 | 355 | 420 | 0 | 0 | 0 |
| % change in drainage network | –59% | 1% | ||||
| % of conduit channels converted to khas land | 45% | 54% | 0% | |||