They can be kilometers long, they can be meters deep, and arguably, they're the most dominant influence on how healthy any coastal marine ecosystem is going to be, because what they do is they're filtering the water constantly, they're holding sand and dirt in place.
Pot avea kilometri lungime, ajungând la metri adâncime. Au, probabil, o influență crucială asupra sănătății  ecosistemului marin de coastă, deoarece filtrează constant apa, fixează nisipul și solul.