Dead Zones in the Ocean
所謂海洋“死區(qū)”是指由于海水富營養(yǎng)化日益嚴重,導致海水中含氧量減少,魚類等生物無法生存的區(qū)域。科學家介紹,人類過量使用化肥、大量生活垃圾、車輛和工廠排放的廢氣廢水等,都使得海水中氮、磷等生物營養(yǎng)物質的含量以越來越快的速度增加,營養(yǎng)積累過剩使海藻等浮游植物大量繁殖,浮游植物死亡及腐爛都消耗海水中的氧,從而使海水嚴重缺氧,這就是富營養(yǎng)化污染。目前全球海洋中約有150處“死區(qū)”,而且數(shù)量還在不斷增多,有些“死區(qū)”面積高達數(shù)萬平方公里。情況最糟糕的一處“死區(qū)”在墨西哥灣,這里的大面積海水嚴重缺氧,魚類等生物根本無法生存。另外,美國東海岸的切薩皮克灣、波羅的海、黑海、亞得里亞海沿岸及泰國灣等海域,均有“死區(qū)”分布。在南美、日本、澳大利亞和新西蘭等海域中也開始出現(xiàn)這樣的區(qū)域。
Are there dead zones in the ocean? Find out on this Moment of Science.
Well, as if we needed one more reason to get our environmental act together, a recent U.N. report warns that the number and size of dead zones in the ocean is increasing.
Dead zones are regions of oxygen-deprived water, where nothing can live. They’re caused by an excess of nutrients–usually nitrogen(氮)–released into the water. When sewage, farm fertilizers, and emissions from vehicles and factories get washed into the ocean, you get what experts call a “nitrogen cascade(氮容器)”. Tiny free- floating organisms known as plankton(浮游生物) feed on all that untreated nitrogen, and multiply to such an extent that they (1)deplete the oxygen supply in the water.
While fish may be able to swim away and avoid (2)suffocation, slower-moving and (3)bottom-dwelling creatures like lobsters(龍蝦), clams(蛤蚌), and oysters(牡蠣) often can’t. Also, the ocean might be a large place, but right now there are 146 known dead zones, some of which span tens of thousands of square miles. One of the worst is where the Mississippi River (4)drains into the Gulf of Mexico, and dumps fertilizer (5)runoff from the Midwest.
Oh,no.Is there anything we can do? We can reduce nitrogen emissions from cars and factories, and implement better sewage treatment. We can plant new forest and grasslands to (6)soak up extra nitrogen and keep it out of the water. And we can develop alternative energy sources(替代能源) that aren’t based on burning fossil fuels(化石燃料).
譯文:
如果我們需要一個理由一起進行環(huán)保行動,那么這個理由就是聯(lián)合國最近的發(fā)布的一個報告警告說海洋死區(qū)的數(shù)量在不斷增多,面積在不斷增大。
海洋死區(qū)是指海水中的氧氣被消耗減少,以致沒有東西能夠生存。它們是由排入水中的過剩的營養(yǎng)物質引起的-這種物質常常是氮。當污水,農田肥料,以及車輛和工廠的排放物被沖刷入海中時,就形成了專家所謂的“氮容器”。像浮游生物這些自由浮動的微小生物就是以未經處理的氮為食。它們繁殖到了如此的程度,以致于耗盡了水中供應的氧氣。
盡管魚可以游走避免窒息,但是那些緩慢移動和底棲的生物,列如:龍蝦,蛤蚌,和牡蠣卻不行?;蛟S海洋是一個廣闊的地方,但是目前已知的海洋死區(qū)已有146個,其中一些跨度數(shù)萬平方英里。最嚴重的地方之一是密西西比河流入墨西哥灣的地方,這里傾倒著從中西部流失過來的肥料。
噢,不。有沒有什么我們可以做的呢?我們可以減少汽車和工廠氮的排放量,并且實施更好的污水治理方法,種植新的森林和草地來吸收多余的氮,并使氮遠離水源。我們還可以開發(fā)不以化石燃料燃燒為基礎的替代能源。
Notes:
(1)deplete [di'pli:t] vt.耗盡,用盡;使衰竭,使空虛
The fire had depleted the game in the forest.
那場大火使森林里的鳥獸瀕臨絕跡。
(2)suffocation [,s?f?'kei??n] n.窒息;悶死
A target that makes her save is immune to suffocation from that elemental for 24 hours.
豁免成功的目標在24小時內免疫這個火元素造成的窒息效果。
(3)bottom-dwelling 底棲生物
marine eellike mostly bottom-dwelling fishes of northern seas.
北部海洋中大多數(shù)底棲的似鰻海魚。
(4)drain into 流入,排入,泄入
The river drains into the sea.
河流向大海。
(5)runoff ['r?n?f, -?:f] n.徑流;決賽;流走的東西 adj.決勝的
So, it is practical to use the sequential clustering and Markov model to forecast the river runoff.
這說明運用馬爾可夫模型進行河徑流量的豐枯狀態(tài)預報是有效可行的。
(6)soak up v.吸收
Soak the spilt tea up with a cloth.
用塊布把灑了的茶水吸干。