52 ENVIRONMENT | MT 5211 natural environment | BT1 geophysical environment | RT flood [5216] | freshwater fishing [5641] | inland waters [1231] | inland waterway shipping [4821] | pollution from land-based sources [5216] | pollution of waterw
52 ENVIRONNEMENT | MT 5211 milieu naturel | BT1 milieu géophysique | RT eaux intérieures [1231] | inondation [5216] | navigation fluviale [4821] | pêche en eau douce [5641] | pollution des cours d'eau [5216] | pollution tellurique [5216]