首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Rainforests may store much less carbon than we thought. It could be time to dramatically revise our estimates following the disc
Rainforests may store much less carbon than we thought. It could be time to dramatically revise our estimates following the disc
admin
2021-09-17
68
问题
Rainforests may store much less carbon than we thought. It could be time to dramatically revise our estimates following the discovery that apparently similar forests hold vastly different amounts of the stuff. The finding is important because there are plans for governments worldwide to compensate tropical countries for protecting their forests as "carbon sinks" to curb global warming. If carbon cannot be counted, then dollars cannot be disbursed (支付).
Greg Asner of the Carnegie Institution for Science in Stanford, California, and colleagues say they used satellite mapping, laser probing of forest undergrowth from aircraft and local ground surveys across a large area of Peruvian rainforest to crack the problem of estimating how much carbon is locked up in forests. But the new technique has revealed a large, previously unknown variability in the density of carbon stored in apparently similar forests.
The Intergovernmental Panel on Climate Change says that there should be about 587 million tonnes of carbon stored in the study area, 43,000 square kilometres of lowland forest in the Madre de Dios region of Peru. But after dividing the area into 40 million individual grid (格子) squares and estimating for each the carbon stored as well as the rate at which it is being fixed and released, Asner says the real figure is just 395 million tones, a third less. "What really surprised us was how carbon storage differed among forest types and the underlying geology," says Asner. For instance, where the underlying rocks are younger, the soils and forests contain more carbon. "There has been no way to uncover these incredible patterns till now."
The study also reveals major carbon loss due to logging, fanning, mining and road construction—even in areas still covered by forest. This "forest degradation" made up almost 50 per cent of all carbon lost from the forest. But the study also found substantial carbon accumulated through natural forest regrowth on abandoned land.
Asner is now conducting similar studies elsewhere round the world, which he says can be used to police the United Nations’ proposed initiative on Reducing Emissions from Deforestation and Forest Degradation in Developing Countries. This scheme would compensate countries that protect their forests to store carbon. It’s important that countries with large rainforests do this, because around 15 per cent of global carbon dioxide emissions come from tropical deforestation.
Markku Kanninen, a forest scientist at the Center for International Forestry Research, a World Bank-backed body based in Bogor, Indonesia, agrees: "This research shows the importance of improving our data on forest carbon. The IPCC global default values are not precise enough for national inventories."
选项
答案
解析
转载请注明原文地址:https://kaotiyun.com/show/nSD7777K
0
大学英语六级
相关试题推荐
GrayingPopulationStaysinthePinkA)Elderlypeoplearegrowinghealthier,happierandmoreindependent,sayAmericanscientis
AdvantagesofPublicTransportA)AnewstudyconductedfortheWorldBankbyMurdochUniversity’sInstituteforScienceandTec
Forthispart,youareallowed30minutestowritealetterofapology.Youshouldwriteatleast150wordsfollowingtheoutlin
Forthispart,youareallowed30minutestowritealetterofinvitation.Youshouldwriteatleast150wordsfollowingtheout
A、Wetendtobesatisfiedafterasecondthought.B、Wearenotalwaysthrilledwiththemafterwards.C、Wealwaysregretthehast
Exerciseisgoodforyou.Butmostpeoplereallyknowverylittleabouthowtoexercise.Lookatthefollowingtrue-falsetests.
Exerciseisgoodforyou.Butmostpeoplereallyknowverylittleabouthowtoexercise.Lookatthefollowingtrue-falsetests.
A、Ithasturnedcertaininsectsintoanewfoodsource.B、IthasstartedtoexpandbusinessoutsidetheUK.C、Ithasimportedso
A、Doubtful.B、Reserved.C、Indifferent.D、Supportive.D从选项预测本题询问的是态度。女士在采访结束时说人们可能对该组织做事的方式持不同看法,但他们做的事情很了不起,希望他们继续并祝他们好运,故选D。长对话
A、Rightaway.B、Intwomonths.C、Earlynextmonth.D、Inacoupleofdays.C从选项预测本题问时间。男士跟女士说下月初她才可以开始上岗,这是否会对她有影响,女士回答说没有影响,故选C。
随机试题
女,38岁。G4P3,孕16周,第一胎5年前,因早孕时患甲型肝炎而行人工流产;第二胎3年前,妊娠34周,早产,新生儿肝脾大,贫血RDS死亡;第三胎,2年前,妊娠33周胎死宫内,娩出时见胎儿水肿,肝脾大,胎盘较大较厚。应做检查为
关于癫痫患者的用药原则,以下说法不正确的是
在一般土层中,确定高层建筑筏形和箱形基础的埋置深度时可不考虑:[2009年第121题]
电缆隧道、工作井的净高,不宜小于1800mm。()
在直方图中,横坐标表示( )。
某建设工程项目承发包双方签订了设计一施工总承包合同,属于承包人工作范围的是()。
马柯威茨均值方差模型所需要的基本输入变量不包括()。
属于融资融券业务的有()
下列有关所得来源地确定的表述中,不正确的是()。
股票期权的执行期限一般()。
最新回复
(
0
)