Ecology 130 Human ecology 44 E ́cologie 33 Ecologie 28 Ecología 28 Zeitschrift 26 Environment 16 Ecología humana 15 Environmental policy 13 Pollution 12 Medio ambiente 11 O ̈kologie 11 Plant ecology 11 Agricultural ecology 10 Environmental protection 10 Environnement 10 Biology 9 Marine ecology 9 Microbial ecology 9 Animal ecology 8 E ́cologie ve ́ge ́tale 8 42.90 ecology: general 7 Conservation of natural resources 7 E ́cologie humaine 7 Environmental Health 7 Environmental Pollution 7 Microbiology 7 Pe ́riodiques 7 Protection 7 Religious aspects 7