Coral reefs are the 'rain forests of the sea', prized for their beauty and resources the world over. They are also one of the earth's most vulnerable ecosystems threatened by climate change. And no place better symbolises their importance and their plight than Australia's Great Barrier Reef. TechKnow's Marita Davison traveled to Queensland to explore the scientific efforts to save one of the world's most iconic ecosystems. The Great Barrier Reef covers 345,000 square kilometres, roughly the size of Germany, and stretches 2300km in length, nearly equal to the entire coastline of Chile. Because it's a living structure on earth, it can also die. While coral reefs cover less than 2% of the ocean floor, nearly 25% of all marine life depends on them for survival. According to the World Resources Institute (WRI), nearly all coral reefs worldwide will be threatened with death by 2050. So why are coral reefs under threat? "There are multiple stressors that face coral reefs like the great barrier reef," explains Dr. Ove Hoegh-Guldberg, Director of Global Change Institute. "There's sediments and nutrients flowing down rivers and smothering corals and other organisms. There has been too much fishing in some cases where we’ve knocked down key species. But the real "show-stoppers" now are the global stressors that we're inflicting on the great barrier reefs." More from TechKnow on: Twitter - https://Twitter.com/AJTechKnow Website - http://aljazeera.com/TechKnow Subscribe to AJE on YouTube - http://aje.io/YTsubscribe