Related by context. Frequent words. (Click for all words.) 68 reefs 66 ocean ecosystems 66 seagrasses 64 seagrass beds 63 coastal ecosystems 63 terrestrial ecosystems 63 coral reefs 63 aquatic habitats 62 ecosystems 62 corals 61 marine ecosystem 61 marine ecosystems 60 marine invertebrates 60 habitats 59 biota 59 aquatic ecosystems 59 freshwater ecosystems 59 reef 58 planktonic 58 foraminifera 58 marine habitats 58 coral reef ecosystems 57 seabeds 57 estuaries 57 intertidal 56 species 56 temperate forests 56 amphibian populations 56 coral 56 habitat fragmentation 56 aquatic ecosystem 56 freshwater mussels 56 benthic 56 Coral reefs 56 estuarine 55 habitat 55 aquatic habitat 55 marine organisms 55 kelp forests 55 marine biodiversity 55 marine sediments 55 ecologies 55 freshwater 55 biosphere 55 coral reef 54 shorelines 54 hydrological cycle 54 coral species 54 species extinctions 54 eel grass 54 ocean acidity 54 harmful algal blooms 54 coral bleaching 54 forest ecosystems 54 mammals 54 aquatic species 54 zooplankton 53 stratospheric ozone 53 biodiversity 53 sealife 53 Algae blooms 53 biodiversity hotspots 53 acidification 53 diatoms 53 headwater streams 53 freshwater lakes 53 alga 53 fauna 53 marine ecology 53 amphibian species 53 waterbirds 53 overfishing pollution 53 tidal wetlands 53 wetland habitats 53 biodiversity hotspot 53 coastal estuaries 53 gobies 53 invertebrates 53 freshwater wetlands 52 seamounts 52 underwater grasses 52 aquatic insects 52 hydrothermal vent 52 streambeds 52 atmospheric methane 52 eelgrass 52 Sperm whales 52 overexploitation 52 Daphnia 52 caribou herds 52 algal bloom 52 pupfish 52 microscopic algae 52 saltmarsh 52 tidal pools 52 fragile ecosystems 51 dinoflagellates 51 algal blooms 51 ecological 51 petrels 51 jumbo squid