There is a warm and humid climate in Aso. It has one of the largest calderas in the world and plants spread around it. If people don't care about the plants, they will be thickets. So through grazing, mowing, or burning off the field, people in Aso maintain the secondary natures.

   Grass resources are used for feed, compost, materials of a roof, fuel, and so on. Burning off the field in Aso is not bad for the environment because it burns off only surface and it maintains biodiversity.

   Aso has many forests and paddy fields, so it keeps a lot of water. This is why Aso is called a water jag of the northern Kyusyu.

Where is "GIAHS" in Aso?