Related by context. Frequent words. (Click for all words.) 62 terrestrial ecosystems 62 boreal forests 62 biodiversity hotspots 62 temperate regions 62 temperate zones 60 biome 59 drylands 59 hardwood forests 59 tropical forests 59 subtropical regions 59 savannas 58 tropical rainforest 58 species 58 savannahs 57 habitats 57 boreal 57 grasslands 56 ecosystems 56 biodiverse 56 arid regions 55 forest ecosystems 55 boreal forest 55 mammal species 55 tropical rainforests 55 marine sediments 55 amphibian populations 55 tropics 55 tropical forest 55 vertebrate species 55 subarctic 55 coral species 55 Polar Regions 55 wetland habitats 54 amphibian species 54 orchid species 54 conifers 54 flora 54 megafauna 54 avian species 54 subtropics 54 taxa 53 barrens 53 mammals 53 landforms 53 crocodilians 53 woodlands 53 river deltas 53 sequoias 53 ecologies 53 Tibetan Plateau 53 subtropical 53 hickories 53 forests 53 continental crust 52 biomes 52 forested 52 bird species 52 lichens 52 tropical climates 52 jack pine 52 savanna 52 grassland 52 freshwater ecosystems 52 habitat 52 lowlands 52 lichen 52 flowering plants 52 aridity 52 peat bogs 52 Giant pandas 52 coral reef ecosystems 51 biologically diverse 51 marine invertebrates 51 atmospheric methane 51 grassland birds 51 mountain glaciers 51 temperate 51 pine forests 51 micro climates 51 tallgrass prairie 51 calcareous 51 coniferous 51 seagrasses 51 semi arid 51 fauna 51 geomorphology 51 stromatolites 51 Arctic tundra 51 rainforests 51 permafrost 51 marine reptiles 50 habitat fragmentation 50 herbaceous plants 50 understory 50 lake sediments 50 temperate climates 50 ant species 50 mammalian species 50 diatom 50 Qinghai Tibet Plateau 50 grasses