The growing of rice in flooded fields.
The growing of rice in land fields.
The removal of rice in flooded fields.
The removal of rice in land fields.
Countries with very hot climate.
Countries with hot and wet climate.
Countries with very cold climate.
Countries with cold and dry climate.
Rice is semi-aquatic, its roots and stems have air tunnels.
Rice is waterproof.
Rice have the same roots as mangrove trees.
Rice can absorb more nutrients in flooded fields.
Here's an interesting quiz for you.