刺胞动物：珊瑚及其保护 Cnidaria: Corals and Protection

珊瑚纲动物生活在海底，是海洋生态系统中的重要成员。它们通常营单体或群体生活，形态各异。水螅型是珊瑚纲动物的主要形态，与水螅纲相比，它们的结构更为复杂。现代珊瑚纲动物全部属于水螅型。

Corals live in the ocean and are important members of marine ecosystems. They usually live alone or in groups and come in all kinds of shapes and sizes. The polyp form is the main form of corals and is more complex in structure compared to the medusa form. All modern corals belong to the hydroid polyp form.

其中，绿海葵是一种没有明显骨骼的珊瑚纲动物，身体像圆柱形，一端附着在其他物体上，另一端的口呈裂缝状，周围还有几圈触手。这些触手上有刺细胞，可以捕捉到一些小动物。绿海葵的口道内有纤毛的口道沟，有助于消化食物。

One of these animals is the giant green anemone (Anthopleura xanthogrammica), which is a type of coral without a skeleton. It has a cylindrical body with one end attached to other objects and a mouth at the other end, which is surrounded by several circles of tentacles. These tentacles have stinging cells that can catch small animals. The green sea anemone also has ciliated grooves in its mouth that aid in digestion.

绿海葵是一种非常神奇的海洋生物，它的消化循环腔结构非常复杂，由体壁的内胚层突出形成许多隔膜，隔膜将消化腔分隔成许多小室，从而起到支持消化腔道和增加消化面积的作用。这些隔膜丝上有丰富的刺细胞和腺细胞，可以进行细胞外和细胞内消化，这可称得上是一种聪明的形制。

The green anemone is a fascinating marine creature with a very complex digestive system. The structure of its digestive cavity is  intricate, with many partitions formed by the protrusion of the inner layer of the body wall. These partitions divide the digestive cavity into many small chambers, supporting the digestive canal and increasing the digestive surface area. The partitions are covered with richly endowed stinging and gland cells, which enable both intracellular and extracellular digestion. It's a really clever design!

而且，海葵还有着独特的繁殖方式。它们是雌雄异体的，生殖腺生长在隔膜上。受精卵在母体内发育，有些海葵则直接发育成为海葵，有些则需要经过浮浪幼虫阶段才能成为新的个体。不同的海葵还有不同的繁殖方式，真是有趣极了！

Furthermore, anemones have a unique way of reproducing. They are dioecious, and their reproductive glands grow on the partitions. Fertilized eggs develop inside the mother and some sea anemones can develop directly into a new individual, while others require a planula stage. Different sea anemones have different methods of reproduction, making them even more interesting!

开放动物学的朋友们可能早有印象，珊瑚礁和珊瑚岛的主要建造者是珊瑚虫。这些珊瑚虫生活在温暖的海洋环境中，多数是以群体的形式生活。它们的外胚层细胞可以分泌出珊瑚骨骼，这些骨骼的堆积就是珊瑚礁和珊瑚岛的基础。比如说，你可能听说或去过我国的西沙群岛或马尔代夫，那里的美丽珊瑚礁可是非常出名的哦！

Did you know that the main builders of coral reefs and coral islands are coral polyps? These small creatures live in warm ocean environments and mostly live in groups. Their outer layer of cells can secrete coral skeletons, which build up over time to form the foundation of coral reefs and islands. For example, you may have heard visited the Xisha Islands in China or the Maldives, both of which are known for their beautiful coral reefs!

但是，珊瑚虫的生存环境要求非常高，它们只能在水温在22到30度之间、水深不超过45米的环境中生存。而且，珊瑚礁对于海洋生物的多样性也有很大的意义，可以说是海洋中的热点地区之一。珊瑚礁甚至还可以在地质尺度下形成储油层，对石油勘探也有帮助。

But coral polyps are also very picky about their living conditions: they need warm water temperatures between 22 to 30 degrees Celsius and can only survive in shallow waters no deeper than 45 meters. Coral reefs are incredibly important for marine ecosystems and support a wide range of marine life. They even have geological significance, as they can form oil reservoirs that are helpful for oil exploration. 

可是，随着环境污染和全球气候变化的影响，珊瑚数量逐渐减少。

However, coral reefs are facing many threats from environmental pollution and climate change, which have caused a decline in their numbers.

据世界濒危物种红色名录，珊瑚早就已经成为了被列入濒危物种名单的海洋生物类群。我们应该共同保护海洋环境，让珊瑚虫和珊瑚礁得到更好的生存和发展。

In fact, corals are now listed as the first endangered marine species on the Red List of Endangered Species. We must work together to protect our oceans and ensure that coral polyps and their amazing coral reefs continue to thrive and grow.

让我们一起行动起来，保护我们珍爱的水体环境吧！通过妥善处理垃圾、合理利用资源的方式，我们可以为海洋生态系统的健康发展尽一份力量。相信只要我们每个人都能从自身做起，共同呵护江河湖海，刺胞动物的生态将会更加丰富，我们的家园也会更加美好！

Let's take action and protect our precious aquatic environment! By properly disposing of garbage and using resources wisely, we can contribute to the healthy development of marine ecosystems. We believe that if each of us starts with ourselves and works together to care for rivers, lakes, and seas, the ecology of cnidarians will become more abundant, and our home will be even more beautiful!