2011/01/11 12:46賴品瑀
摘譯自2011年1月5日ENS美國，俄勒岡州，科瓦利斯報導；張桂芳編譯；蔡麗伶審校
奧勒崗州立大學一位科學家警告說，儘管漂浮在太平洋上的塑料垃圾量大到「令人不安」的地步，但她卻不諱言表示，介於美國加利福尼亞州和日本之 間的太平洋大垃圾帶是美國德克薩斯州兩倍大的説法過於誇張。 擔任奧勒崗州立大學海洋學系助理教授的安琪懷特（Angel White）表示，一直聲稱自20世紀 50年代以來，該垃圾帶每十年增長了十倍，而且充斥海洋中的塑料遠比浮游生物來得多的説法實為「嚴重誇大。」
幾年前懷特參與了一項難得專為探究隨處可見的塑料碎片和塑料對微生物群影響的考察團。
該考察於2008年8月25至9月5日間進行。活動由美國國家科學基金會(National Science Foundation)贊助，透過總部設於美國檀香山夏威夷大學的微生物海洋學中心：研究和教育(C-MORE)執行。
懷特說，如果就塑料垃圾帶本身實際面積而言，而不是整個垃圾帶環繞的北太平洋環流，其中「聚集在一塊」的塑料帶，事實上根本不到德州1%的面積。
懷特還表示「那裏的塑料垃圾量的確不少。 但是，即便引用任何科學家曾經提供過的最高密度數據所得到的垃圾帶大小，也只有德州面積的一小部分般大而已，而不至於到它的兩倍大小。」
她還說，最近一項聲稱太平洋大垃圾帶的深度有如金門大橋那麽高，是完全沒有根據的理論。
微生物和塑料之間的微妙關係是引發懷特與她的C-MORE同事進行這些研究的原因。考察行程中，他們發現光合微生物依附在許多塑料顆粒上，生意盎然。
懷特進一步表示，雖然這些塑料可能有利於某些微生物的生長，但同時也可能是有毒的。她關心的是，許多侵入性物種可能藉著漂浮物而遷移到較敏感脆弱的棲地。
她接著表示:「一方面，這些塑料可能有助於排除水中毒素。另一方面，同樣的這些帶有毒素的顆粒可被魚類和海鳥誤食。因此，顯然塑料不該出現在海中。」
懷 特最後表示:「從這些例子中總結來說就是，我們就把海洋垃圾帶的數量並不如傳説的那麽糟視為一個好消息，但要清除這些塑料的費用卻貴得令人望而卻步。所 以，如何防止更多的垃圾污染我們的海洋，應該是未來努力的重心。CORVALLIS, Oregon, January 5, 2011 (ENS)
There is a "troubling" amount of plastic trash floating in the Pacific Ocean, warns an Oregon State University scientist, but she is debunking claims that the Great Pacific Garbage Patch between California and Japan is twice the size of Texas.
Angel White, an assistant professor of oceanography at Oregon State, says claims that the patch has been growing tenfold each decade since the 1950s and that the oceans are filled with more plastic than plankton are "grossly exaggerated."
White took part in one of the few expeditions solely aimed at understanding the abundance of plastic debris and the impact of plastic on microbial communities.
The expedition, which took place August 25 through September 5, 2008 was part of research funded by the National Science Foundation through C-MORE, the Center for Microbial Oceanography: Research and Education, based at the University of Hawaii in Honolulu.
If you look at the actual area of the plastic itself, rather than the entire North Pacific Gyre in which it cycles, the "cohesive" plastic patch is actually less than one percent of the geographic size of Texas, White says.
"The amount of plastic out there isn't trivial," White said. "But using the highest concentrations ever reported by scientists produces a patch that is a small fraction of the state of Texas, not twice the size."
One recent claim that the Great Pacific Garbage Patch is as deep as the Golden Gate Bridge is tall is completely unfounded, White said.
The relationship between microbes and plastic is what drew White and her C-MORE colleagues to their analysis. On their expedition, they discovered that photosynthetic microbes were thriving on many plastic particles.
While plastic may be beneficial to some organisms, it can also be toxic, White confirms, and she is concerned that floating debris may allow invasive species to migrate into sensitive habitats.
"On one hand, these plastics may help remove toxins from the water," she said. "On the other hand, these same toxin-laden particles may be ingested by fish and seabirds. Plastic clearly does not belong in the ocean."
"If there is a takeaway message, it's that we should consider it good news that the garbage patch doesn't seem to be as bad as advertised," White said, "but since it would be prohibitively costly to remove the plastic, we need to focus our efforts on preventing more trash from fouling our oceans in the first place."
全文及圖片詳見：ENS
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