altitude typology: | |
high: > 800 m, mid-altitude: 200 - 800 m, lowland: < 200 m | |
depth typology based on mean depth: | |
< 3 m, 3 - 15 m, > 15 m | |
size typology based on surfcae area: | |
0.5 to 1 km², 1 to 10 km², 10 to 100 km², > 100 km² | |
geology: | |
calcareous, siliceous, organic |