深水珊瑚林

Deep-Sea Coral Forest

2018年在南海发现的深水珊瑚林,为底栖生物乃至碳循环研究弥补了重大空缺。受技术限制,以前深海底栖生物的研究主要局限在沉积覆盖的软基底,以为石质海底是一片贫瘠世界。1990年代中期,应用深潜技术首先在大西洋发现了深海珊瑚礁,为海洋科学开辟了新的研究方向。深海珊瑚包括两类:一类是属于六方珊瑚的石珊瑚,以其文石质的外骨骼形成珊瑚礁;另一类是以柳珊瑚为主的珊瑚林,柳珊瑚属于八方珊瑚,可以形成高镁方解石的骨骼。这些碳酸盐骨骼都能够记录深海的环境变化,是古海洋学研究的绝佳材料。太平洋由于文石补偿面过浅,不利于深水珊瑚礁发育,深水珊瑚林应当普遍发育,可惜至今尚未得到重视,绝大部分海域属于研究空白。通过对深水珊瑚礁和珊瑚林的组成以及分布的介绍,讨论深水珊瑚林在海洋生态学中的重要性及其在古海洋学再造中的意义。

The discovery of deep sea coral forests in the spring of 2018 filled a significant gap in the benthos research and even in carbon cycling in the South China Sea.Previously,the researches of deep-sea benthos were restricted to the sediment-covered soft bottom due to the technical limitations,and the rocky hard bottom was believed to be barren of life.Using submersible technique in the mid-1990 s,deep-water coral reefs were first discovered in the Atlantic Ocean,which opened a new research direction in marine sciences.Two groups of deep sea corals have been recognized:scleractinian hexacorals and gorgonian octocorals.The aragonite skeleton of the former group build up deep sea coral reefs,while the latter make up deep sea coral forests with high-Mg calcite skeleton in many gorgonian corals.All kinds of carbonate coral skeletons can record environment changes of the deep sea and provide excellent material for high-resolution paleoceanography.Although the development of deep sea coral reefs in the Pacific Ocean is hampered by its extremely shallow aragonite compensation depth,deep sea coral forests are ubiquitous in the ocean.Up to now,most parts of the Pacific have not yet explored in this respect,and deep sea corals remain outside the research scope.The present paper is a literature review and calls for attention to the deep sea forests.It starts with the composition and distribution of deep sea coral reefs and forests,followed by discussions on the significance of deep sea coral forests in marine ecology and in paleoceanographic reconstructions.