海洋的九大危機

海洋的九大危機

賴鵬智譯

一、過漁 Overfishing

許多海洋學家認為過漁（過度撈捕）是人類對海洋最壞的影響。聯合國糧食及農業組織估計全世界超過70％的魚種已經被撈光、枯竭。撈捕的速度快過魚類繁殖生長的速度，我們已嚴重危害整個海洋生態系，無論是掠食魚種或是被掠食的魚種，牠們之間的食物鏈關係已經被破壞。這樣的損傷使得其他的干擾（如污染）更容易威脅海洋生態系。為了永續海洋資源，必須有一個全面翻修的漁業政策，這就須要全世界各國通力合作才行。

Many marine scientists consider overfishing to be the worst impact humans are having on the oceans. The Food and Agriculture Organization estimates that over 70% of the world’s fish species have been entirely exploited or depleted. By capturing fish faster than they can reproduce, we are harming entire ecosystems that interact with those species, from the food they eat to the predators that eat them. These losses make the ecosystems more vulnerable to other disturbances, such as pollution. A complete overhaul of fishing policies, requiring global cooperation, is needed to achieve a sustainable system. 

二、沒良心的養殖漁業  Irresponsible Fish Farming

野生漁獲減少，水產養殖業就更形發達。理論上養殖漁業是個好主意，但因為不當的經營管理導致許多負面的結果。養殖飼料、水產糞便、化學藥品（譯按：如抗生素、消炎藥、清潔劑）都很容易流進開放的大海而影響海洋生態。養殖的魚也有可能在不經意間流入海洋而有嚴重影響，例如消滅原生族群、傳播疾病及破壞棲地等。不幸的是，想要克服這些問題卻很不容易，因為供應全球將近50％魚貨的養殖漁業在目前並沒有很好的管制。 

Fish farming, or aquaculture, is the growing response to wild fish stocks rapidly depleting. While it sounds like a good idea in theory, it unfortunately has many negative consequences due to poorly managed operations. Nutrient and chemical pollution can occur easily in open-ocean operations when fish feed, excrement, and medication is released into the environment. Farmed fish accidentally released into wild populations can also have destructive effects, such as loss of native stocks, disease transmission, and damaging changes in habitat. Unfortunately, the biggest hindrance to overcoming the challenges of an industry that supplies nearly 50% of the world’s fish food supply is that it currently remains relatively unregulated.

三、幽靈撈捕 Ghost Fishing

遺失或丟棄的漁具在海中繼續纏捕魚類或其他海洋生物稱之為「幽靈撈捕」（或譯「幽靈漁撈」），是對海洋生態極大的傷害。這種情形往往造成連鎖問題，例如小型生物被廢棄漁具纏住，大型掠食生物前來捕食，卻也一起被纏住。漂流的漁具也可能被捲進螺旋槳而損害船隻。現在有許多解決辦法被提出，例如以生物可分解的材質製造漁具，或像南韓政府收購老舊的漁具，鼓勵漁民更新（對海洋生態較友善的）魚具。

Ghost fishing is an environmentally harmful issue caused when lost or discarded fishing gear continues to catch fish and other marine life. Often times, the traps trigger a chain-reaction problem when larger predators come to eat the smaller ones that have been ensnared, only to get tangled in the mess themselves. The issue of ghost fishing is most common with passive gear that has been abandoned, and also poses a serious threat to other ocean vessels. Stray gear can be caught in the propeller of a boat, damaging or even disabling it. Many solutions have been offered, such as fishing gear made from biodegradable materials or incentives like the Republic of Korea’s buy-back program, which rewards fisherman for turning in old gear.

四、垃圾 Garbage

這是明顯易見的問題。真是令人驚訝這些垃圾是如何倒進大海的。海洋生物很容易被人類的垃圾纏住或困住，美麗的珊瑚與海綿也會被摧毀。更甚者，塑膠袋會被海龜或海豚視為牠們最喜愛的食物—水母或魷魚而吞食，造成牠們窒息或阻塞消化系統。如果您認為這樣還沒什麼，那麼在太平洋有一個比美國德州面積更大的垃圾漩渦及另一個規模稍小一點的位在大西洋，就應該是個警鐘了吧！

This one is the most obvious. It’s astounding how much of our trash finds its way into the ocean. Animals become easily entangled and trapped in our garbage, and it can destroy delicate sea life like coral and sponges. In addition, sea turtles and dolphins often mistake plastic bags for their favorite foods, jellyfish and squids, choking them or clogging their digestive system. If that’s not bad enough, hopefully the bigger-than-Texas trash vortex in the Pacific Ocean and its smaller cousin in the Atlantic will help serve as a wakeup call. 

五、酸化 Acidification

海洋吸收了地球將近1/3的二氧化碳，讓地球可以不那麼熱但也使得海洋表面更酸。但這樣也限制了珊瑚、浮游生物及其他海洋生物利用碳酸鈣製造骨骼或保護用的外殼（譯按：這部分道理請參閱2010年2月9日科學月刊「二氧化碳濃度與海水酸化」或是2008年12月7日中國時報B4/科學周報「海水升溫+酸化 珊瑚遭『雙殺』」）。工業革命後海洋酸化程度增加25％，如果以這樣的速度繼續酸化下去（譯按：就是人類繼續大量排放二氧化碳），許多海洋生命將因此消逝。 

The ocean absorbs as much as one third of the CO2 emitted worldwide, which keeps us cooler but makes the ocean surface much more acidic. This has the effect of limiting calcium carbonate needed by coral, plankton, and other marine life that use it to build the skeletal frames and shells that protect them. Oceanic acidity has increased by 25% since the industrial revolution, and will eventually destroy much marine life if it increases at this rate.

六、優養化 Dead Zones

七、水銀污染 Mercury Pollution

八、海上鑽油 Offshore Drilling

海上鑽油一直是個爭議，但顯然的只要石油持續開採，就會加劇對海洋的傷害。使用石化燃料會使海洋更熱而且更酸，但海上鑽油帶來的危機不只如此。當石油從海底被往上汲取時，連帶會有許多重金屬如汞、砷、鉛等都被提出來。同時偵測油源的震波也對海洋哺乳動物造成傷害或使鯨豚驚慌失措。2008年全球最大石油業者艾克森美孚公司就是使用震波科技時導致100隻鯨擱淺。而運輸油料的基礎設施會造成海岸侵蝕，則又是另一個問題了。（譯按：其實本文沒有提及另一嚴重問題，就是意外發生時，石油流洩污染海洋的夢魘。） 

九、取鯊魚翅及捕鯨 Shark Finning / Whaling

原英文報導： 

9 Problems Destroying Our Oceans (PHOTOS)