the brief introduction of land-based fish farming

    the technology of land-based fish farming is the lastest and well-recognized scientific research achievement, developed by shanghai fisheries research institute and shanghai fishery technical extension station. the project of land-based fish farming was passed the authentication in dec,2000. experts in aquaculture regarded the project as "a leading technology at home and advanced one abroad, due to its creative way of culture, advanced technological design, the unique and effective hardware and the perfect land=based fish farming technology." "the research achievement of land-based fish farming technology provides a completely new mode of modern technology in fish farming. it has successfully resolved the problems caused by the traditional aquaculture, such as environment pollution and make it possible to culture marine fish species in shanghai and inland provinces. it's a revolution of aquaculture in chinese history." the project was awarded a first-class prize for advance in science and technology bye shanghai science committee in dec, 2001 and gained the patent of invention, as well as other newly-practical patents.
the land-based fish farming which in based on land and high-technique,makes the culture environment and process controllable artificially and effectively. it is a closed recirculating system for aquaculture, and could be free from the effect of natural water environment on aquaculture. it can be used either for fresh water aquaculture or for marine culture. its main features are as follows:
1. high density in small water body. the capacity per cubic meter can reach 25 to 50 kilos for aquatic product, 50 times larger than traditional pond fish culture, with a capacity of 0.5 to 1 kilos. so the resource of land can be effectively saved through land-based fish farming.
2. water-saving. land-based fish farming consumes only 5% volume of water as much as traditional pond culture needed to produce the same yield. it's a model of water-saving agricultureal project.
3. electricity-saving. it only consumes 10 watts of electrical power to purify 1 metric ton of water while the previous factory fish farms and the current oversea land-based fish farming faclilties usually need with and average of more than 200 watts.
4. health, environment protection and non-pollution. it adopts closed and recirculating water treatment technology to ensure 99% of the water being recycled and reused. the water quality in the course of production is strictly monitored and controlled to prevent from any enternal impact to culture so that the cultured products can meet the demands of green, safe and healthy standard. there is no discharge of wastes and no pollution the natural environment.
5. energy-saving. controlling the water temperature can be realized through its small culture water body, thus making scientific fish faming and all-reason production in an optimal temperature and high oxygen environment and reducing the farming periods. furthmore, it is possible to adopt solar energy or off-peak electrical power to heat water to reduce the cost of production.
6. technology with small system and large combination. each culture pond, equipped with physical and biological treatment facilities forms and independently running system. the investors can make the system any intensive production scale according to their demands of abilities of investment. this unique technology can also make it possible for the investor to raise fish with different temperature of salinity in a combined system and the various fish can grow up uninterferedly with each other just as the chinese saying goes"they reign over their own territory and never interfere with each other." it can also prevent the fish from cross infection of fish diseases while the multi-species production would bring about enormous flexibility to fish farms to satisfy the different market demands.
along with the various advantages, the land-based fish farming technology also has some inevitable drawbacks, such as the need of continuously electrical power, all-day attendance and the trained technical workers. compared with the traditional pond farming the operation cose and hardware investment is high that make the land-based fish farming technology temporally unlikely to be extended in today's china where the traditional aquaculture still plays a major role in the supply of aquatic products. but it is convinced that the traditional aquacuture will give way to land-based fish farming with the country becomes stronger and the environment law is perfectively established. nevertheless. the development of land-based fish farming even at present, still finds its significant importance in the following aspects:
1. through selecting and advantageous location we can apply the land-based fish farming equipment to the urban big markets with wholesale or auction, including the importing and exporting markets. all the goods in the market can be transacted transparently.
2. it's a necessary project in the modern agriculture garden and a show window of modern fisheries. it can also be used as a spot or scene for popularizing scientific education and sightseeing agriculture.
3. it can be used poduce high-value aquatic products. it's cost-effective to adopt this technology for production of fish at a price of 40 rmb/kg and with a period of no more than 6 months from fingerling to marketable size fish. it is alse profitable for holding of taste-change culture and the off-season production. besides, the land-based fish farming technology will play an important role in those giant aquatic enterprised to produce secure, healthy an dgreen seafood.
4. in water shortage area, such as the western provinces of china, it is practical to use the land-based fish farming equipment for the production of marine or freshwater fish.
the land-based fish farming i a sustainable developing cause which extends a broad and promising future due to an active response to the developing needs of urban aquaculture, equipment aquaculture and modern aquaculture. the foreign opinion has considered the "the prospects for land-based fish farming is like a new type of trawling fleet to catch fish without the necessity to run the risk of sea-going. it shows how the increasing world-wide problem is eventually being resolved completely."