Table 2 Driving forces and possible effects

 Distance to river (m)

Marshland near river exhibited fewer loss

 Elevation (m)

Marshland in lower areas more prone to loss

 Slope (°)

Marshland loss is more likely to occur in flat areas

 Average annual precipitation (mm)

The marshland loss rate increase with decrease precipitation

 Average annual temperature (°C)

Marshland are more likely to be converted at warmer temperatures

 Potential crop yield (kg/km²)

Marshland are more likely to be converted when potential crop yields are high

 Distance to settlement (m)

Marshland tend to be vulnerable to losses when adjacent to residents

 Distance to road (m)

 Gross domestic product (yuan/km²)

Marshland distributed in the poor areas are more likely to be lost

 Population density (persons/km²)

Marshland loss is more likely to occur in high-density population areas

 Ditch density (length/km²)

Marshland in the region with high ditch density are more likely to be prone to loss