Most often it is red, but actually nowadays you can get almost any color you like.

紅色是最常見的，但現今幾乎想漆成什麼樣的顏色都行。

The reason for it goes back to the earliest days of sailing ships.

船被漆成這樣的原因要追溯到帆船時代的早期。

Back in those days, wooden sailing ships would slowly plot around the world.

在當時，木製的帆船在世界各地緩慢地航行著。

A combination of their slow speed and rough hull made them an ideal breeding ground for underwater growth.

他們緩慢的速度與粗糙的船殼表面，造就了對水下生物來說完美的繁殖場。

Just take a look under a pier, you will see the sort of growth these ships used to suffer, which would be barnacles, worms, seaweed, and things like that.

往隨便一個碼頭底下看去，便能看到曾讓這些船隻深受困擾的水下生物，包含了藤壺、蠕蟲、海草等等。

So what's the issue?

所以這有什麼問題？

Well, all of these things have negative impacts on ships over time.

這個嘛，這些東西在長久下來會對船隻有不良影響。

You get the obvious of things like damage to the hull itself due to worms and the actual growth,

明顯的問題包含因為蠕蟲與海生植物對船殼本身造成的損壞，

then you get issues like the additional weight that they have to carry around, and reduction in maximum speed due to the extra drag.

還有這些生物等於船隻的額外載重，並且會因為其造成的阻力而使船隻的行駛速度下降。

Of course on sailing vessels, that drag-on weight would impact their ability to sail upwind, which would yet further reduce their efficiency.

而理所當然的，這種附加的重量會使帆船逆風而行的能力變差，進一步降低效率。

What you need is a way to stop marine life from growing on the bottom of the hull, and this is where antifouling comes in.

這使得人們必須想出能夠讓水中生物不要在船殼上成長的方法，而這就是抗污技術大顯身手的時候了。

Antifouling, fairly obviously, is just a system designed to reduce fouling by animal and plant life on the underwater sections of a boat or a ship.

抗汙技術顧名思義，就是一種設計用來防止動物或植物在船隻吃水線以下的部分造成汙損的系統。

Early solutions were to place copper sheets on the hulls of ships.

早期的解決方案是在船殼上覆蓋一層銅板。

The Cutty Sark is a great example of this, and I'll link to the Greenwich Maritime Museum below if you want to see more about that.

卡蒂薩克號便是一個很好的例子。如果你想了解更多關於這艘船的資訊，可以查閱我附在資訊欄中，格林威治海洋博物館的連結。

The primary purpose of the copper sheets was actually to stop worms eating their way through old wooden hulls.

銅板的主要目的是防止蠕蟲侵蝕並吃穿木製的船殼。

A secondary benefit though, is that the copper would reduce the growth of plant life.

而它帶來的第二個好處，則是銅能夠減緩植物的生長。

Of course, as wooden hulls were replaced by iron, worm issues did reduce, but they've never been eliminated.

當然，隨著木製船殼被鐵製船殼取代，蠕蟲的問題確實減少了，但不代表就此消聲匿跡。

Just look at the leisure industry today, and you'll still see plenty of wooden hulls around.

看看現今休閒用船隻產業，便仍能在許多船上發現木製船殼。

And of course regardless of its construction material, we still have the same old issue of drag caused by the growth of plant life.

而不論船殼的材質為何，船體上生長的水生植物仍會造成減緩船隻速度的老問題。

It's probably more important now to keep that under control, what were the cost of fuel and efficiency savings on long passage.

控制這樣的問題在現今甚至可能反而更加重要，因為它是遠途航程中燃油成本與效率低落的原因之一。

We still need antifouling to stop a combination of worms barnacles and weed from growing on the underside of hulls.

我們仍然需要抗汙技術來阻止蠕蟲、藤壺和海草在船殼上生長。

But instead of using the old technique of copper sheets, we now use a form of paint instead.

但我們不再使用過去的銅板覆蓋法，而是使用一種特定的塗料。

That antifouling paint works on the same principle and actually still uses copper as a biocide, though is mostly cuprous oxide now mixed in with the paint rather than copper sheets.

抗汙塗料的原理與銅板相同，而且仍使用了銅做為生物滅除劑，但現在主要使用的是混在塗料中的氧化銅，而不是一塊塊的銅板。

It's the natural red color of those copper oxides that's led to the traditional red color of antifouling.

而正是這些銅氧化物自然的紅色色澤，讓傳統抗汙塗料有著經典的紅色色彩。

Modern antifouling systems can be broken down into two broad categories: hard and soft.

現代抗汙系統可以大略分為兩大類：硬式與軟式。

Soft coatings are designed to wear off over time, continuously exposing fresh biocides as the outer layer of the paint wears off.

軟式塗層會隨著時間逐漸褪去，在外層塗料剝落的同時持續性地釋放出新的生物滅除劑。

Hard coatings on the other hand are designed to be a lot more durable. They're meant to last a lot longer.

在另一方面，硬是塗料則設計得更能持久使用。他們能持續更長時間。

As the biocides are released, the durable layer of paint remains, but of course the biocides contained in the outermost layer do get used up.

在生物滅除劑被釋放出來的同時，耐用的塗層仍保持在船殼上。但在最外層中的生物滅除劑當然仍會隨時間演進而耗盡。

Both systems work on the same principle: They gradually release biocides, commonly based on the chemical element copper.

兩種系統的運作原理相同：都是逐漸釋放出通常以銅為基底的生物滅除劑。

The difference is that soft coatings slowly allow the paint to flake off as well.

兩者不同的是，軟式塗料會使噴漆也跟著慢慢剝落。

As you can imagine there are environmental considerations to think of.

而如你所能想見的，這背後還有環境保護的疑慮。

No matter what way you look at it, antifouling releases biocides, and possibly paint, into the environment.

無論從哪個角度去看，抗汙塗料都會像環境釋放出生物滅除劑，有時還有可能會釋放出噴漆。

That is one reason a lot of ports don't allow cleaning of hulls. They don't want the extra dose of biocides and paint released by the scrubbing process.

這也是許多港口不允許清理船殼的原因之一。他們不想要接受洗刷過程中可能釋放出的額外生物滅除劑與噴漆。

So what are your other options?

那麼你有什麼其他選擇呢？

The cleanest one is to simply use normal hardware and paint on the other side of the hull, but that will result in a lot of aquatic growth.

最乾淨的選擇便是使用普通材質的船殼，然後在吃水線下也漆上一樣的噴漆。但這麼做會使船殼上布滿水生植物。

That's fine on a small boat that you can pull out of the water and clean quite often, but is not so great on a container ship running around the world.

如果是一艘能夠經常拉到岸上清潔的小船那倒還好，但對於經常在世界各處到處航行的貨輪來說則不怎麼理想。

What would happen if, for example, a container ship picked up some seaweed in Asia and carried it into the Baltic Sea, where it takes hold and overtakes some of the native species?

而且假如，舉例來說，有一艘貨輪在亞洲停留時讓一些海草附到了上面去，然後把這些海草帶到了波羅地海，並讓它們在當地蓬勃發展並取代了一些原生物種呢？

Similar things have happened, and do actually continue to happen.

過去曾發生過類似的事情，而且確實仍在持續發生。

Though it's not so much from hull growth because of antifouling. It's more of an issue for a ballast water, but that's a topic for another video.

雖然主要的原因其實不是抗汙塗料，而是壓艙水所造成的問題。不過我們到另一個影片再來討論吧。

So aside from just using no antifouling, what could you do?

所以除了完全不使用抗汙塗料以外，你還能怎麼做？

There is talk of systems that slowly ooze some sort of jelly from the hull.

有人提出了一個會慢慢從船殼內滲出某種凝膠的系統。

The theory is that as the growth attaches to the hull, the oozing jelly seeps off and takes the growth away with it.

理論上當水生植物附到船殼上時，凝膠便會從船殼滲出，並和水生植物一起脫落。

I've never seen that in use, but if anyone has, let me know in the comments below, because it'd be fascinating to look into.

我從來沒看過實際運用時的情況，但如果有人有看過的，請在評論欄中留言告訴我。看起來肯定相當有意思。

Otherwise, there are some silicon based paints that make it hard for barnacles and things to stick to the hull itself.

其他的辦法還有以矽膠為基底的噴漆，它能讓藤壺與其他生物更難附著到船殼上。

Unfortunately, these don't actually stop the growth, but it makes it easier to clean off.

遺憾的是，它們實際上無法阻止水生植物的生長，但能夠使其更好被清除。

Said that, most ports don't allow cleaning anyway, not only because of the historical antifouling issues, but also they don't want to clean off species that are not native to the harbor itself.

說是這麼說，大部分的港口根本不允許船隻清潔船殼，而這不但是因為抗汙塗料一直以來的問題，還有他們並不想清理本來不屬於該港口原生生物的其他物種。

The last thing they want is to be overcome by some sort of invasive weed from the other side of the world.

他們可不想解決遠從世界的另一頭而來的侵略性海草。

Anyway, hopefully you've enjoyed today's video, and have liked learning about the paint on the bottom of the hull.

無論如何，希望你喜歡今天的影片，並高興自己學到了關於船殼底部噴漆的知識。

For more content like this every other Friday, be sure to subscribe right here on the channel.

我們每個星期五會發布更多類似的內容，所以記得在這裡訂閱本頻道。

Until next time, thank you for watching, and good bye.

直到下次再見，感謝收看。