Related by context. Frequent words. (Click for all words.) 52 biodiversity hotspot 51 Aral Sea 50 Greater Mekong 49 Soil erosion 48 rampant deforestation 48 Cholera outbreak 48 Kala azar 47 HIV Aids epidemic 47 invasive insect 47 Desertification 47 Kyrgyzstan Tajikistan 47 Poyang Lake 47 devastations 47 Severe drought 47 river deltas 46 Lake Natron 46 coastland 46 Omo River 46 Tien Shan 46 deltaic 46 taiga 46 Amazonian rainforest 46 Poliomyelitis 46 Kola Peninsula 46 cyclone Aila 46 Greater Mekong Sub 46 Devastating floods 46 Balkan Peninsula 45 Africas 45 Quake jolts 45 Dongting Lake 45 wetland ecosystems 45 severe droughts 45 Tropical Cyclone Nargis 45 temperate rainforest 45 Mekong River 45 Tibetan Plateau 45 virgin forest 45 monsoon floods 44 sub Sahara 44 sub Saharan Africa 44 tropical forest 44 Taihu Lake 44 periodic droughts 44 Danube Delta 44 Melting glaciers 44 Amur River 44 Buruli ulcer 44 Tajikistan Kyrgyzstan 44 Mekong river 44 Qinghai Tibet Plateau 44 Lao Cai province 44 Tidal waves 44 archipelagic nation 44 Quake shakes 44 bird flu epidemic 43 ecological 43 Mekong delta 43 Bohai Sea 43 deciduous forests 43 tiger habitats 43 avian influenza outbreaks 43 temperate forests 43 Xishuangbanna 43 Mekong 43 Amazon Rainforest 43 rinderpest 43 Radiation leaks 43 cyclone Sidr 43 desertification 43 Illegal logging 43 Maniema 43 ecological degradation 43 drylands 43 prolonged droughts 43 lowland forests 43 Quang Tri province 43 arid lands 43 biodiverse 43 ecological catastrophe 43 elephant poaching 43 Thar Desert 43 freshwater ecosystems 42 Southeast Asia 42 Amu Darya 42 Asia 42 bio diversity 42 continent 42 deadly cholera epidemic 42 palm plantations 42 virgin forests 42 Africa 42 Typhoon Lekima 42 amphibian populations 42 biodiversity 42 Tarim Basin 42 indigenous cultures 42 IWRM 42 Sahelian 42 Boreal forest 42 cholera epidemics