Green cactus in the ocean desert

There is a famous macro photography diving spot near Tawali Resort in Papua New Guinea, which is called Laoadi by local people, and it is about 25 minutes' boat ride from Tawali. It is the intersection of two rivers, and it is a slope composed of black volcanic sand, which is covered with many green algae called Halimeda. There are two kinds of giant salamanders in the waters of New Guinea, one is the giant salamander, and the other is the columnar salamander. As the name implies, H. marcoloba is generous, and H. cylindracea is slim. If we carefully observe these two kinds of green algae, we can often find many marine animals living in them, such as small flower branches and fairy palm ghost dragons. Just observe every moray eel patiently.

Why can halim flourish without being eaten by herbivorous fish? The reason is that abalone will secrete toxic secondary metabolites, which will reduce the chances of herbivorous fish eating. At the same time, abalone will also migrate chloroplasts at night, making the color white and not causing the appetite of herbivorous fish. Therefore, many marine animals know how to hide in Halimeda to avoid predators' attacks, and even change color with Halimeda. For example, Fairy Palm Ghost Dragon will turn green or white. In addition, the cell wall of abalone is highly calcified, which makes the texture hard, which is also the main reason why herbivorous fish don't like abalone. Because of this, Halimeda decomposed after death is the source of marine white calcium carbonate sand.

Another diving spot I like very much is the observation point, which is located in the northwest corner of Normanby Island, about 3? Hours, locals will take a bus here to other islands. The water here is yellow sand mixed with shiny mica and covered with many fallen leaves. Colorful sea lilies are often attached to sea lilies, and there are ghost dragons of corresponding colors on sea lilies. If you carefully search for fallen leaves and Halimeda, you can also find many different kinds of sea slugs, and ships will even stop here.

The next time you see a sandy slope in the South Pacific where hard corals can't grow in large numbers, please don't think that you can't find all kinds of creatures here. In fact, Halimeda green algae also plays a role in keeping small marine animals alive.

Scientific classification

Kingdom: plants

Division: Chlorophyta

Class: Bryophyceae

Objective: bryozoa objective.

Family: Haliotidis.