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StillnessOcean ecosystem fact

Kelp forests grow in cool coastal seas from giant brown algae, not plants, and shelter a great variety of fish, invertebrates, seals and sea otters.

NOAA Ocean Service

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The story behind the card

Kelp are large brown algae. Instead of roots they have a grip-like base called a holdfast, and gas-filled bulbs hold their fronds up towards the light. Giant kelp can grow up to about 60 centimetres a day and reach more than 30 metres, forming a canopy at the surface like the treetops of a forest. Kelp forests grow along cool coasts from California and Chile to South Africa, Australia and Norway. In the North Pacific, sea otters help protect them by eating sea urchins, which graze on kelp. Where otters were hunted out for their fur, urchins multiplied and stripped forests down to bare rock, leaving what are called urchin barrens.

Türkçe oku
Kelp ormanları bitkilerden değil, soğuk kıyı sularında yetişen dev esmer alglerden oluşur. Birçok balığa, omurgasıza, foka ve deniz samuruna barınak olur.

Kelpler büyük esmer alglerdir. Kökleri yoktur; onun yerine kayaya pençe gibi tutunan bir tabanları vardır. Gazla dolu küçük keseler de yapraksı kısımlarını ışığa doğru ayakta tutar. Dev kelp günde 60 santimetreye kadar uzayabilir ve boyu 30 metreyi geçebilir; su yüzeyinde, bir ormanın ağaç tepeleri gibi bir örtü oluşturur. Kelp ormanları Kaliforniya ve Şili'den Güney Afrika'ya, Avustralya'ya ve Norveç'e kadar soğuk kıyılarda yetişir. Kuzey Pasifik'te deniz samurları, kelpleri kemiren deniz kestanelerini yiyerek bu ormanları korur. Samurların kürkleri için avlanıp yok edildiği yerlerde deniz kestaneleri çoğaldı ve ormanları çıplak kayalığa çevirdi.

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Background reading: Kelp forest
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