Off the coast of Formentera, an island
进入查看：2022-2023学年英语周报九年级第1期答案汇总
以下内容仅作展示，图片上方文字进入查看。
Off the coast of Formentera, an island, lives seagrass that stretches 15 km. The seagrass, covering several kilometers, is made up of a single organism. The grasses are also long-lived, for tens or hundreds of thousands of years. Along with two other kinds of coastal ecosystem – mangrove (红树林) swamps and tidal marshes (潮汐沼泽) – seagrass fields are particularly good at taking carbon dioxide from the air.
This role was highlighted in a report published on March 2nd by UNESCO, on “blue carbon” – the carbon stored by Earth’s oceanic and coastal ecosystems. In total around 3,300 million tons of carbon dioxide (about three-quarters of the world’s emissions in 2019) are locked away in the planet’s blue-carbon sinks. Research by Carlos Duarte, the report’s author and an ecologist, has shown that one hectare of seagrass can suck as much carbon dioxide each year as 15 hectares of rainforest.
One reason that blue-carbon ecosystems make such effective sinks is that underwater forests are thicker than the land-based woods. They can also trap floating pieces and organic matter, which settles on the sea floor and can double the amount of carbon stored away. They possess another advantage, too. Climate change is leading to more wildfires around the world. As forests burn, their carbon stocks are sent back into the atmosphere. Unlike forests on land, blue-carbon ecosystems do not burn.
