1. Introduction
In the context of the growing global demand for food and the increasing pressure on terrestrial resources, the development of deep – sea aquaculture pastures has emerged as a significant solution. China, with its vast marine territory and a long – standing tradition in aquaculture, is actively promoting the construction of green and sustainable deep – sea aquaculture pastures. These pastures not only have the potential to enhance food security by increasing the supply of high – quality aquatic products but also play a crucial role in promoting sustainable development and protecting the marine ecological environment.
2. Current Status of China’s Deep – Sea Aquaculture Pastures
2.1 Development History
China’s exploration of deep – sea aquaculture began in the 1990s when gravity – type cages were introduced and popularized. Since then, with the continuous support of national policies and the progress of science and technology, the industry has been advancing by leaps and bounds. In the “13th Five – Year Plan” period, driven by policy guidance, technological innovation, and market demand, large – scale equipment – based aquaculture such as truss – type cages and aquaculture workboats has developed rapidly. Provinces along the coast, including Shandong, Guangdong, Fujian, and Hainan, have witnessed a boom in the construction of large – scale equipment for deep – sea aquaculture.
2.2 Existing Scale
By the end of 2023, coastal regions across the country had built more than 20,000 gravity – type cages, which are mainly used in waters with a depth of 20 meters. These cages are currently the most common and mature deep – sea aquaculture mode. In addition, 40 truss – type cages have been established, such as the “Dehai No.1” truss – type cage in Guangdong, which has withstood the test of a typhoon of magnitude 17. Moreover, there are 4 aquaculture workboats, among which the “Guoxin No.1” aquaculture workboat in Shandong is a 100,000 – ton – class vessel that adopts the innovative “ship – borne cabin aquaculture” technology and can carry out migratory aquaculture. The total deep – water aquaculture volume in the country has reached 43.98 million cubic meters, with a production of 390,000 tons, showing a significant increase compared with the initial stage of the “13th Five – Year Plan”.
2.3 Technological Achievements
In recent years, China has made remarkable technological achievements in deep – sea aquaculture. In terms of aquaculture equipment, the research and development of anti – wave and anti – current equipment, high – strength anti – fouling netting, and automatic and precise feeding systems have been promoted. For example, some deep – sea cages are equipped with advanced monitoring systems that can real – time monitor water quality, temperature, and the growth status of aquaculture species. In terms of breeding technology, efforts have been made to breed excellent aquaculture varieties suitable for deep – sea environments. Although there is still a certain gap compared with developed countries, continuous progress has been made in the fields of disease prevention and control, feed formulation, and intelligent management.
3. Significance of Green and Sustainable Deep – Sea Aquaculture Pastures
3.1 Ensuring Food Security
As the world’s population continues to grow, the demand for high – quality protein is also increasing. Aquatic products are an important source of high – quality protein. The development of deep – sea aquaculture pastures can expand the production space of aquatic products, effectively increasing the supply of aquatic products and alleviating the pressure on the food supply. With the improvement of people’s living standards, the demand for high – quality and pollution – free aquatic products is also on the rise. Deep – sea aquaculture, with its relatively clean water environment, has the potential to produce high – quality aquatic products, which can meet the needs of the domestic market and enhance China’s food security.
3.2 Promoting Sustainable Development
Compared with traditional near – shore aquaculture, deep – sea aquaculture has the advantage of less impact on the marine ecological environment. By transferring aquaculture activities to the deep – sea area, the over – crowded situation in near – shore waters can be alleviated, reducing problems such as eutrophication and disease transmission in near – shore aquaculture. At the same time, the development of green and sustainable deep – sea aquaculture pastures emphasizes the rational use of resources, such as the use of clean energy in aquaculture equipment and the implementation of scientific feeding methods to reduce waste. This helps to achieve the coordinated development of the aquaculture industry and the ecological environment, which is in line with the concept of sustainable development.
3.3 Protecting the Marine Ecological Environment
Properly planned and managed deep – sea aquaculture pastures can play a positive role in protecting the marine ecological environment. Some aquaculture species can filter seawater, absorb nutrients, and help improve water quality. For example, seaweed aquaculture can not only produce economic benefits but also absorb carbon dioxide and nitrogen and phosphorus nutrients in the water, playing a role in purifying the water environment. In addition, the development of deep – sea aquaculture can also drive the improvement of marine environmental monitoring and management capabilities, which is conducive to the overall protection of the marine ecological environment.
4. Challenges Faced by the Development of Deep – Sea Aquaculture Pastures
4.1 Technological Bottlenecks
4.1.1 Aquaculture Equipment
Although China has made certain achievements in the research and development of deep – sea aquaculture equipment, there are still some problems. The stability and durability of some equipment need to be further improved. For example, in the face of typhoons and strong ocean currents in the deep – sea area, some cages may be damaged, which not only affects the safety of aquaculture but also causes potential environmental pollution. In addition, the cost of some advanced equipment is too high, which restricts its large – scale promotion. The development of key equipment such as underwater cleaning robots and mechanized fish – gathering and harvesting equipment is still in its infancy, and there is a lack of complete sets of equipment systems.
4.1.2 Breeding Technology
The selection of aquaculture varieties suitable for deep – sea environments is still a challenge. At present, the number of excellent deep – sea aquaculture varieties in China is relatively limited. Some important seedlings, such as salmon and white – leg shrimp, still need to be imported. The breeding technology of deep – sea aquaculture varieties needs to be further improved. The traditional breeding technology has limitations in improving the disease – resistance and growth rate of aquaculture species. Molecular breeding technology, although promising, has not been widely applied due to its high technical difficulty and cost. In addition, the research on disease prevention and control in deep – sea aquaculture is still insufficient, and there is a lack of effective early warning and treatment systems for common diseases.
4.2 High Costs
4.2.1 Equipment Construction and Maintenance Costs
The construction of deep – sea aquaculture pastures requires a large amount of investment in equipment. The construction cost of large – scale cages, aquaculture workboats, and supporting facilities is extremely high. For example, the construction of a 100,000 – ton – class aquaculture workboat like “Guoxin No.1” requires a huge amount of capital. In addition, due to the harsh deep – sea environment, the maintenance cost of equipment is also very high. Regular inspections, repairs, and replacements of equipment parts are necessary, which further increases the operating cost of deep – sea aquaculture.
4.2.2 Operational Costs
The operation of deep – sea aquaculture pastures also incurs high costs. The transportation of feed, personnel, and products between the deep – sea area and the shore requires a lot of resources. The high – cost of long – distance transportation increases the overall cost of aquaculture. In addition, the cost of energy consumption in deep – sea aquaculture, especially for equipment that requires continuous power supply such as water quality monitoring systems and aeration equipment, is also a significant expense item.
4.3 Environmental Risks
4.3.1 Natural Disasters
The deep – sea area is often affected by natural disasters such as typhoons, tsunamis, and strong ocean currents. These natural disasters pose a great threat to the safety of deep – sea aquaculture pastures. Typhoons can cause the destruction of aquaculture equipment, the escape of aquaculture species, and even endanger the lives of aquaculture workers. Tsunamis and strong ocean currents can also damage equipment and disrupt the normal growth environment of aquaculture species. Although some preventive measures can be taken, accurately predicting and effectively coping with natural disasters in the deep – sea area is still a major challenge.
4.3.2 Ecological Impact
Although deep – sea aquaculture has the potential to be more environmentally friendly than near – shore aquaculture, improper development may still have an impact on the marine ecological environment. High – density aquaculture may lead to the accumulation of residual bait and fish excrement, increasing the content of organic matter, nitrogen, and phosphorus in the water, which may cause local eutrophication. In addition, the introduction of some non – native aquaculture species may have an impact on the local ecological balance if not properly managed.
5. Development Strategies for Green and Sustainable Deep – Sea Aquaculture Pastures
5.1 Strengthening Technological Innovation
5.1.1 Equipment Research and Development
Increase investment in the research and development of deep – sea aquaculture equipment. Encourage scientific research institutions and enterprises to cooperate to develop more stable, durable, and cost – effective aquaculture equipment. For example, research on new materials for cages to improve their anti – wave and anti – corrosion capabilities. Strengthen the development of key equipment such as underwater cleaning robots, automatic feeding systems, and mechanized fish – gathering and harvesting equipment to improve the automation and intelligence level of deep – sea aquaculture.
5.1.2 Breeding Technology Innovation
Vigorously promote the innovation of breeding technology. Increase investment in the research and development of deep – sea aquaculture varieties, and use modern breeding technologies such as molecular breeding and gene editing to cultivate aquaculture varieties with strong adaptability, high disease – resistance, and high economic value. Strengthen the research on disease prevention and control technology in deep – sea aquaculture, establish a complete disease early – warning and treatment system, and reduce the impact of diseases on aquaculture production.
5.2 Cost – Control Measures
5.2.1 Equipment – Related Cost Control
In terms of equipment construction, optimize the design of aquaculture equipment to reduce unnecessary costs while ensuring performance. Promote the standardization and modularization of equipment to improve production efficiency and reduce production costs. For equipment maintenance, establish a scientific maintenance plan, use advanced maintenance technologies and tools, and improve the efficiency of equipment maintenance to reduce maintenance costs.
5.2.2 Operational Cost Control
Optimize the transportation route between the deep – sea aquaculture area and the shore to reduce transportation costs. Explore the use of new energy sources in deep – sea aquaculture, such as solar energy, wind energy, and wave energy, to reduce energy consumption costs. In addition, improve the management level of deep – sea aquaculture pastures, optimize production processes, and improve production efficiency to reduce overall operating costs.
5.3 Environmental Risk Management
5.3.1 Natural Disaster Prevention
Strengthen the construction of a marine disaster monitoring and early – warning system. Use advanced satellite remote sensing, radar, and buoy monitoring technologies to accurately predict natural disasters such as typhoons and tsunamis. Develop emergency response plans for natural disasters, and regularly organize drills to improve the ability of deep – sea aquaculture pastures to respond to natural disasters. Strengthen the reinforcement of aquaculture equipment to improve its resistance to natural disasters.
5.3.2 Ecological Protection
Carry out scientific environmental impact assessments before the construction of deep – sea aquaculture pastures, and determine reasonable aquaculture density and species according to the carrying capacity of the marine environment. Promote the development of multi – trophic – level integrated aquaculture models, such as the combination of fish, shellfish, and seaweed aquaculture, to achieve the recycling of nutrients in the aquaculture system. Strengthen the monitoring of the marine ecological environment around deep – sea aquaculture pastures, and take timely measures to address any negative impacts on the environment.
6. Future Development Prospects
6.1 Market Outlook
With the continuous improvement of people’s living standards and the increasing awareness of healthy eating, the market demand for high – quality aquatic products will continue to grow. Deep – sea aquaculture, with its advantages of producing high – quality and pollution – free aquatic products, has broad market prospects. In the domestic market, as the income level of urban and rural residents increases, the consumption of high – end aquatic products is expected to show a significant upward trend. In the international market, China’s deep – sea aquaculture products also have the potential to gain a larger share with their excellent quality, which will promote the further development of the deep – sea aquaculture industry.
6.2 Industrial Chain Expansion
The development of deep – sea aquaculture pastures will drive the expansion and improvement of the entire industrial chain. In the upstream, it will promote the development of industries such as aquaculture equipment manufacturing, feed production, and seedling breeding. For example, the demand for high – quality aquaculture cages, advanced monitoring equipment, and specialized deep – sea aquaculture feed will increase, which will stimulate the innovation and development of related industries. In the downstream, it will promote the development of aquatic product processing, cold chain logistics, and sales industries. The emergence of more deep – sea aquaculture products will require more advanced processing technologies to increase product added value, and a more perfect cold chain logistics system to ensure the freshness of products, and the expansion of sales channels to reach more consumers.
6.3 Contribution to Sustainable Development
In the long run, green and sustainable deep – sea aquaculture pastures will make important contributions to China’s sustainable development. In terms of the economy, it will become a new growth point for the marine economy, driving employment and economic growth. In terms of the environment, it will help to protect the marine ecological environment and achieve the coordinated development of economic development and environmental protection. In terms of food security, it will provide a stable supply of high – quality aquatic products, ensuring the stability of the national food supply.
7. Conclusion
China’s green and sustainable deep – sea aquaculture pastures have broad development prospects. Although facing some challenges such as technological bottlenecks, high costs, and environmental risks, through strengthening technological innovation, implementing cost – control measures, and effectively managing environmental risks, these challenges can be gradually overcome. The development of deep – sea aquaculture pastures is of great significance for ensuring food security, promoting sustainable development, and protecting the marine ecological environment. With the continuous efforts of the government, scientific research institutions, and enterprises, China’s deep – sea aquaculture industry is expected to achieve leapfrog development in the near future, making important contributions to the global aquaculture industry and sustainable development.
