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StillnessDeep-ocean ecology fact

Marine snow is a continuous fall of organic particles, including plankton remains, mucus, faecal pellets and other debris, from upper waters into the deep sea.

Marine snow

OceanBiologyClimateScience

The story behind the card

Much of this material is eaten or broken down by bacteria on the way, and only a small fraction settles on the seabed, yet it is the main food supply for many deep-sea animals, far below where sunlight lets algae grow. Flakes grow as particles clump together and can sink tens to hundreds of metres a day. The name is often traced to the naturalist William Beebe, who saw particles drifting in his lights during bathysphere dives off Bermuda in the 1930s. Scientists measure the fall with sediment traps and underwater cameras, because it is a key part of the ocean's biological carbon pump: carbon taken up by plankton at the surface sinks, and what reaches the seabed can stay there for centuries or longer.

Türkçe oku
Deniz karı, plankton kalıntıları, mukus, dışkı topakları ve başka organik parçacıklardan oluşur. Bu parçacıklar üst sulardan derin denize durmadan yağar.

Bu parçacıkların çoğu yolda yenir ya da bakteriler onları ayrıştırır; deniz tabanına ancak küçük bir kısmı ulaşır. Yine de güneş ışığının ulaşmadığı, alglerin yetişemediği derinliklerde birçok canlının başlıca besin kaynağı budur. Tanecikler birbirine yapışarak büyür ve günde onlarca, hatta yüzlerce metre batabilir. Adın, 1930'larda Bermuda açıklarında batisferle dalan doğa bilimci William Beebe'ye dayandığı söylenir; Beebe projektörlerinin ışığında süzülen tanecikleri görmüştü. Bilim insanları bu yağışı tortu tuzakları ve su altı kameralarıyla ölçer, çünkü okyanusun biyolojik karbon pompasının önemli bir parçasıdır: yüzeyde planktonun aldığı karbon batar, tabana ulaşan kısmı ise yüzyıllarca, hatta daha uzun süre orada kalabilir.

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Background reading: Marine snow
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