own onigawa's shut down prevented major damage. the iaea experts will investigate what impact there was on the demonstration of the pikes and pulls of nuclear fuel. >> when you look at all three units, at this point, because it is the beginning of the mission, we have not any focused area to look at. so once we look at the information, we will decide where we will look and what areas. >> they will also research the sea wall around onigawa. the structure is believed to have helped the plant with standard tsunami in contrast to the break wall at fukushima daiichi. the iaea experts hope to use their findings to strengthen the quake resistance of plants around the world. nhk world, from onigawa. >>> one of the world's natural wonders, australia's great barrier reef, is under growing pressure from shifting tides of climate and industry. a recent conference sounded the alarm over the future of the world heritage site. nhk world has more. >> reporter: stretching more than 2,000 kilometers of the most eastern state of queensland, the great