A new study says the worlds tropical coastal forests store more planet-warming carbon dioxide than almost any other ecosystem.But rapid loss of these forests - known as mangroves - is releasing substantial and previously unrecognized quantities of greenhouse gases into the atmosphere. Mangroves provide rich breeding grounds for fish, and they help buffer coastal areas from storm surges. But their role in trapping climate-warming carbon dioxide has not been studied much. A new study in the journal Nature Geoscience provides a first look. More carbon per hectare than tropical rainforests Daniel Donato with the Forest Service of the U.S. Department of Agriculture and his colleagues surveyed tree mass, dead wood, and soil carbon in 25 mangrove ecosystems around the tropical Indian and Pacific Oceans. Donato says study shows, They are right up there with the most carbon-rich forests in the world. Donatos results showed mangroves store about three to four times more carbon per hectare as temperate forests or even tropical rainforests. But Donato says most of it is hidden. Carbon in mangroves is really about the below-ground story, he says. Most of the carbon stored in that ecosystem is in the soil and the tree roots. Mangroves stored about five times as much carbon in deep soils compared to temperate or tropical forests. Rapid loss But the researchers note that a third to a half of the worlds mangroves have been cut down in the last half-century for timber, coastal development and aquaculture. The researchers estimate that the amount of greenhouse gases released each year from mangrove deforestation may be equivalent to as much as 10 percent of the global toll from deforestation.Thats despite the fact that mangroves make up less than 1 percent of the tropical forest area. Donato says the research should get the attention of policymakers.It shows mangroves are probably pretty good candidates for things like carbon-market trading to encourage sustainable forest management. Dollar value Carbon markets, where industries buy the right to emit carbon dioxide in exchange for protecting forests or other offsets, could be a powerful force for conservation, environmentalists say. Many developing countries, especially in Asia, are clearing mangroves for fish and shrimp aquaculture because it can be profitable. The value of the mangrove often is not immediately obvious to policymakers, says Emily Pidgeon, director the marine climate change program at the environmental group Conservation International. By suddenly having an actual mechanism to value these systems in dollars, it gives you a potentially very large new mechanism for countering the other financial and economic arguments, she says. Consumer standards Other groups are approaching the economics of mangrove conservation from the buyers side. They are encouraging Western supermarkets and other large consumers to only buy farmed seafood that meets certain standards, including limited impact on mangrove loss. Pidgeon says it works well in some places. But other developing countries are not equipped to meet or enforce the standards. The government structures are not very strong, she says, and the expertise and capacity to apply some of these approaches is often very challenging. Mosaic of services One of the most important ways to help local communities value the mangroves, Pidgeon says, is to see them as part of a mosaic that provides a whole range of services, including nurturing the fisheries that many developing-world coastal fishing communities depend on for their livelihoods. Although you may catch your fish in one particular piece of the mosaic, the fish are only there to catch because of the time they spend in all the other pieces, she adds. For many coastal communities, carbon storage is just the latest service they may see mangroves providing. Daniel Donato A mangrove landscape on the Ganges River Delta, Bangladesh. Mangroves are being rapidly deforested globally.
英语名篇名段背诵精华27
精选英语美文阅读:How selfless real love is 无私的爱
浪漫英文情书精选:Is It Love?这是爱么?
精选英语美文阅读:爱的奇迹 Keep on Singing
精选英语美文阅读:哪有一株忘忧草? (双语)
精选英语美文阅读:你见或者不见我(中英对照)
双语美文欣赏:孤独人生
精选英语美文阅读:无雨的梅雨天 (双语)
英文《小王子》温情语录
精选英语美文阅读:被忽略的爱 Helpless love
爱情英语十句
态度决定一切 Attitude Is Everything
美文欣赏:海边漫步
英语美文:一双丝袜(有声)
浪漫英文情书精选:My Everything我的一切
浪漫英文情书精选:Good Morning早上好
精选英语美文阅读:A Friend's Prayer 朋友的祈祷
英语美文:生命这个奇迹
精美散文:爱你所做 做你所爱
生命可以是一座玫瑰花园
双语美文:I Wish I Could believe
精选英语美文阅读:饶孟侃《呼唤》
双语阅读:回家的感觉真好
精美散文:守护自己的天使
26个英文字母蕴含的人生哲理
浪漫英文情书精选:My Heart And Soul我的灵魂
英语晨读:忘忧树
英语美文:A Psalm of Life 人生礼颂
最美的英文情诗:请允许我成为你的夏季
英语美文:越长大越孤独(双语)
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |