《海洋殺手》Killing Ourselves Quickly…

我們的海洋是地球的生命維持系統。它提供食物,氧氣,改變我們的沿海環境,調節我們的大氣和氣候。長期以來,人類一直依賴海洋及其看似巨大的資源,而很少關心保護。然而,在過去的100年中,我們的人口從1914年的18億增長到72.1億(ANU)。加上工業發展,化石燃料的使用和消費主義經濟,我們對世界海洋施加了不可估計的壓力。海洋暖化的速度超過了預期,對世界的氣候造成了嚴重破壞。

我們的海洋維持著地球上的所有生命,但我們繼續忽視它,損害了無數海洋生物,並污染了我們最重要的資源之一。在保護環境的鬥爭中,海洋健康應該是第一任務。

在這裡,我們想談論我們海洋的困境,以及我們如何在此過程中令人類步入滅亡。

海洋酸化
在過去的200年中,全球海洋酸度增加了30%。我們海洋不斷變化的酸度有可能破壞海洋生命的化學平衡。酸化的基本科學原理是海洋通過自然過程吸收二氧化碳,但是按照我們通過燃燒化石燃料將其泵入大氣的速率,海洋的pH平衡值下降到了海洋生物難以應對的地步,海洋酸度增加會導致碳酸鹽短缺,阻止了一些動物(和植物)需要建造其外殼和骨骼的關鍵構件;這些動物包括蛤蜊、蠔、螃蟹、龍蝦和珊瑚等。而珊瑚是珊瑚礁的框架建設者,但珊瑚礁是迄今為止我們海洋中最多樣化的生態系統,然而珊瑚礁不會停止酸化的作用。珊瑚只是骨牌效應中的第一塊骨牌,具有破壞整個海洋的震撼力。

過度捕撈
許多海洋科學家認為過度捕撈是人類對海洋造成的最嚴重影響。據估計,全世界超過70%的魚類被開發或消耗掉。通過捕獲繁殖快的魚類,包括它們食用的食物到食用它們的捕食者,這些都是我們正在破壞整個生態系統的原因。這些損失使生態系統更容易受到其他干擾,例如污染。但需要徹底改革捕撈政策,需要全球合作,以實現可持續的系統。

不負責任的魚類養殖
水產養殖,或養魚業,是對迅速耗盡海洋魚類資源的日益增長的反應。雖然這聽起來是個好主意,但不幸的是,由於操作不善,它會帶來許多負面影響。水產養殖的主要問題是效率:生產一隻魚需要5至20條魚作為飼料。當魚類飼料、排泄物和藥物釋放到環境中時,在開放海洋作業中會容易發生營養和化學污染。養殖魚類可能會意外地釋放到野外,造成破壞性影響,例如喪失本地種群,傳播疾病和破壞生境。不幸的是,克服這個行業所面臨的挑戰的最大障礙是,該行業提供了世界近50%的魚類食品,目前仍處於相對不受監管的狀態。

鬼網捕魚
鬼網捕魚是對環境有害的問題,這是説明丟棄的漁網或釣線繼續捕獲魚和其他海洋生物時造成的後果。通常,當較大的捕食者嘗試吃掉被困住鬼網中較小的魚類時,這個陷阱會引發連鎖影響,而鬼網捕魚的問題最常見於已被廢棄的被動漁具,尤其是延繩捕魚。

失去特定物種
海洋最重要的捕食者被淘汰會產生嚴重的後果,影響到食物鏈。每年有50至1億條鯊魚被殺死,這是從漁船上捕獲的副漁獲物,或者是被直接捕撈鯊魚背鰭的鯊魚,魚翅都被廣泛用在亞洲。鯊魚被切掉鰭放回水中後,通常很難生存並流血至死。不幸的是,鯊魚繁殖相當緩慢,並且沒有大量後代,因此人類這些行為對它們脆弱的生態系統產生了長期的影響。儘管1986年暫停了許多種類的捕鯨活動,但這仍然是一個問題,日本等一些國家正在尋找漏洞,並遊說推翻這些法例。

失去珊瑚礁
保持珊瑚礁健康是當前的另一個主要問題。考慮到珊瑚礁支持著大量的小規模海洋生物,因此如何保護珊瑚礁是非常重要,它不僅滿足了即時食品需求,而且從經濟角度上也支持了更大的海洋生物和我們人類。全球暖化造成珊瑚白化的主要原因,但也有其他原因。科學正在研究各種方法,但是這也與設定「海洋保護區」有關。找出保護珊瑚礁這個「生命支持系統」的方法是我們海洋整體健康的重點。

海底鑽油
海底鑽油一直是一個爭論,但是很明顯,增加石油產量只會加劇我們海洋的兩難局面。化石燃料的使用是令我們的海洋不斷升溫和變得更加酸性的原因,但是海底鑽油的風險更大。從海底提取石油時,其他化學物質(例如汞,砷和鉛)也會隨之產生。此外,地震波還發現了存在石油,危害了水生哺乳動物和鯨魚。 2008年,由於埃克森美孚(ExxonMobil)使用這些技術進行石油勘探,結果有100條鯨魚擱淺。此外,運輸石油的基礎設施經常侵蝕海岸線,造成更多的問題。

汞(水銀)污染
科學家報告說,在過去20年中,我們海洋中的汞(水銀)含量上升了30%以上,並且在未來幾十年中還將繼續上升50%。燃煤發電廠的排放是主要的罪魁禍首,它釋放出有毒的汞,這種汞一直沿著食物鏈向上傳播,最終通過我們食用的魚來到我們身體。這種神經毒素會影響胎兒大腦的發育,並造成學習障礙。

海洋死區
海洋死區是海床中溶解氧很少或沒有溶解氧的區域。這些地區通常在大河口處發現,主要是由徑流中攜帶的肥料引起的。這種缺氧會殺死許多生物並破壞整個棲息地。按照我們目前的速度,死區將在本世紀末之前增加50%。

海洋垃圾
海洋是我們地球上最大的生命資源之一,但它也是我們最大的垃圾場。令人震驚的是,我們有非常多垃圾進入海洋。動物糾纏並被困在我們的垃圾中;破壞了珊瑚和海綿等精緻的海洋生物;海龜和海豚經常嗆死在塑料袋上(誤以為是水母或魷魚)或塑料碎片堵塞鳥類和其他海洋哺乳動物的消化系統使他們餓死。如果這還不夠糟糕,那麼希望太平洋上比德克薩斯州還大的垃圾漩渦能夠有助於喚醒人類。

我們的藉口還有甚麼?如果仍然繼續我們的生活方式,人類確實處於滅絕的過程中。

原文內容:

《Ocean Geographic》:Facebook & IG

Killing Ourselves Quickly…

Our ocean is the Earth’s life-support system. It provides food, oxygen, shapes our coastal environments, regulate our atmosphere and climate. Through the ages, mankind has relied on the ocean and its seemingly immense resources with little concern for conservation. However, in the last 100 years, our population grown from 1.8 billion in 1914 to 7.21 billion (ANU); coupled with industrial development, the use of fossil fuel and a consumerism economy, we have placed immeasurable stress on our world’s ocean. The ocean is getting warmer faster than predicted, creating havoc to the world’s climate.

Our ocean sustains all life on earth and yet we continue to neglect it, harming innumerable marine life, and polluting one of our most important resources. In the battle for preservation of our environment, the health of our oceans should be number one priority. Here, we would like to shed some light on the plight of our ocean, and how we are killing ourselves rapidly in the process.

Ocean Acidification
Ocean acidity has increased by 30% globally during the last 200 years. The changing acidity of our ocean threatens to throw off the delicate chemical balance upon which marine life depend for survival. The basic science behind acidification is that the ocean absorbs carbon dioxide through natural processes, but at the rate at which we are pumping it into the atmosphere through burning fossil fuels, the ocean’s pH balance is dropping to a point where life within the ocean is having trouble coping. Increased acidity in the ocean would lead to a shortage of carbonate, a key building block some animals (and plants) need to build their shells and skeletons; these animals include shellfish like clams, oysters, crabs, lobsters and corals. Corals are the framework builders of reefs, by far the most diverse ecosystem in our ocean. The effects of acidification will not stop with coral reefs; corals are simply the first piece in a domino effect with sweeping impact that will be felt throughout the ocean.

Overfishing
We are vacuuming all life out of the ocean as thought resources are infinite. In truth, we are already scratching the bottom of the barrel. Many marine scientists consider overfishing to be the worst impact humans are causing on the oceans. The Food and Agriculture Organization estimates that over 70% of the world’s fish species are either exploited or depleted. By capturing fish faster than they can reproduce, we are disrupting entire ecosystems that interact with those species, from the food they eat to the predators that eat them. These losses make the ecosystems even more vulnerable to other disturbances, such as pollution. A complete overhaul of fishing policies, requiring global cooperation, is needed to achieve a sustainable system.

Irresponsible Fish Farming
Aquaculture, or fish farming, is the growing response to rapidly depleting fish stock in ocean. While it sounds like a good idea, it unfortunately has many negative consequences due to poorly managed operations. The main problem with aquaculture is efficiency: 5 to 20 fish are needed as feed to produce one fish. Nutrient and chemical pollution can occur easily in open-ocean operations when fish feed, excrement and medication are released into the environment. Farmed fish may accidentally be released into the wild, with 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.

Ghost Fishing
Ghost fishing is an environmentally harmful issue, caused when discarded fishing nets or lines continue to catch fish and other marine life. Often, the traps trigger a chain-reaction when larger predators come to eat the smaller ones that have been ensnared, only to get themselves entangled in the mess. The issue of ghost fishing is most common with passive gear that has been abandoned, especially with the long liners.

Loss of Sentinel Species
Decimation of the ocean’s most important predators has significant consequences that ripple down the food chain. 50 to 100 million sharks are killed each year, either as bycatch from fishing vessels or directly hunted for their dorsal fins, used in an expensive soup popular across Asia. When finned, the sharks are thrown back into the water, often still alive and left to bleed to death. Unfortunately, sharks reproduce fairly slowly and do not have a large number of offspring, so these actions have long-lasting repercussions on the delicate ecosystems they help regulate. Despite the 1986 moratorium on many types of whaling, it still continues to be a problem, with some nations like Japan looking for loopholes and lobbying for lax regulations.

Loss of Coral Reefs
Keeping the coral reefs healthy is another major issue right now. A focus on how to protect the coral reefs is important, considering coral reefs support a huge amount of small sea life, which in turn supports both larger sea life and us, not only for immediate food needs but also economically. Global warming is the primary cause of coral bleaching, but there are other causes as well. Science is working on ways, but it also is a matter of setting aside marine conservation areas. Figuring out ways to protect this “life support system” is a must for the overall health of our ocean.

Offshore Drilling
Offshore drilling continues to be a debate, but it is clear that greater oil production would only exacerbate the dilemmas of our oceans. The use of fossil fuels is the reason our oceans have been heating up and becoming more acidic, but offshore drilling takes the risks even further. When oil is extracted from the ocean floor, other chemicals like mercury, arsenic, and lead come up with it. In addition, the seismic waves used to find oil harm aquatic mammals and disorient whales. In 2008, 100 whales had beached themselves as a result of ExxonMobil exploring for oil with these techniques. Furthermore, the infrastructure transporting oil often erodes the coastline, creating more problems.

Mercury Pollution
Scientists report that mercury levels in our ocean have risen over 30% in the last 20 years, and will continue increase another 50% in the next few decades. Emissions from coal power plants are the primary culprit, dispensing poisonous mercury that works its way up the food chain, eventually coming to us through the fish we eat. This neurotoxin affects the development of the brain in foetuses and has been linked to learning disabilities.

Dead Zones
Dead zones are areas of the sea floor with little or no dissolved oxygen. These areas are often found at the mouths of large rivers, and are caused primarily by fertilizers carried in runoff. This lack of oxygen kills many creatures and destroys entire habitats. At our current rate, dead zones will increase by 50% before the end of this century.

Garbage
The oceans are among our biggest resource for life on earth, but it is also our biggest dumping ground. It is astounding how much of our trash finds its way into the ocean. Animals become entangled and trapped in our garbage, delicate sea life like coral and sponges are destroyed, sea turtles and dolphins often choke on plastic bags (mistaking them for jellyfish or squid) or plastic bits clog up the digestive system of birds and other marine mammals causing them to starve to death. If that is 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.

The dinosaurs did not see the meteors coming. What is our excuse? Continue the way we live, we are truly on the course of extinction.

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