The deep sea has been documented as the largest biome on earth. Typical deep-sea ecosystems such as hydrothermal vents, cold seeps, seamounts, oceanic trenches, and whale falls, shattering the early understanding of the deep sea as a "no-go area" for life. However, the difficulty of deep-sea access, limited by the technology of deep-sea equipment, has limited human insight into the unique environment characterized by high pressure, high/low temperature, limited light, and nutrient scarcity in the deep sea. So far, less than 1 ‱ of the whole deep-sea ecosystem has been visually observed or physically sampled. In-depth understandings of biodiversity, function, and service of the deep-sea ecosystem, and the impact by anthropologic activity are far from well known. Thus, it is critical to developing technologies that can obtain deep-sea organisms, ecosystem development, and interactions with environmental changes.
This study is led by Prof. Si Zhang (Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), China). A bibliometric analysis over the past five decades showed that there was a strong interrelation between the types of deep-sea equipment and the research hotspot of the deep-sea organisms. Recently, the research of deep-sea organisms is gradually shifting from identifying species and environmental characteristics to exploring ecosystems and connectivity.
Research achievements are closely in line with the developing technologies. Deep-sea submersibles, microbial bioreactors, seafloor observatory, and molecular biology methods have promoted the discovery of new species in the deep sea, bringing new opportunities to study the adaptability of deep-sea organisms to extreme environments, as well as biological connectivity. These technologies can assist in achieving the controlled culture of deep-sea organisms with specific ecological service functions, providing a new window for exploiting high-value deep-sea biological resources.
Innovating deep-sea equipment performance is essential to break through the bottleneck of deep-sea organism research. In the future, advanced and specialized equipment that meets the requirements of deep-sea organism research must be developed for exploring, surveying, observing, sampling, experimenting, and conducting models in the deep-sea floor environment. Different perspectives of research on the biology of deep pelagic and benthic ecosystems should be considered as well.The main areas of innovation are as follows:
1. Improving the ability to explore deeper, wider, and longer-term deep-sea ecosystems
2. Developing large-scale in-situ conditions-retaining simulators
3. Enhancing the self-adaption ability of the deep-sea environment
The research team is working on building a long-term underwater laboratory that can carry three scientists and multiple devices into the deep-sea cold seep ecosystem for long periods of time to conduct multiple in-situ experiments and long-term investigations. Also, the team is building a long-period and large-scale simulator to create an artificial ecosystem of deep-sea cold seep.
