Region
China
6
Europe
4
United States
4
European Economic Community countries
2
Great Britain
2
New Hampshire
2
Sweden
2
Arid regions
1
Chine
1
Czechoslovakia
1
England
1
European Union countries
1
Friuli
1
Germany
1
Germany (West)
1
Hubbard Brook Experimental Forest
1
Hubbard Brook Experimental Forest (N.H.)
1
Hubbard Brook Valley
1
Italy
1
Japan
1
Mendota, Lake
1
Nile Valley
1
North America
1
North Carolina
1
Ontario
1
Philippine Islands
1
Pinatubo, Mount (Philippines)
1
Polar regions
1
Solar system
1
Stockholm (Province)
1
Sudbury (District)
1
Sultan Alonto, Lake
1
Wisconsin
1