Search results
Results from the WOW.Com Content Network
For trout, stocking rates of 30 to 50 kg/m 3 are normal at the end of a rearing cycle, while for marine species, such as sea bass and sea bream, the achievable load is lower, between 15 and 20 kg/m 3. The total volume required for a raceway is calculated by dividing the total amount of fish in kg by the desired stocking rate in kg per m 3. [17]
To produce one kilograms of farmed salmon, products from several kilograms of wild fish are fed to them – this can be described as the "fish-in-fish-out" (FIFO) ratio. In 1995, salmon had a FIFO ratio of 7.5 (meaning 7.5 kilograms of wild fish feed were required to produce one kilogram of salmon); by 2006 the ratio had fallen to 4.9. [ 103 ]
A maize crop yielding 6–9 tonnes of grain per hectare (2.5 acres) requires 31–50 kilograms (68–110 lb) of phosphate fertilizer to be applied; soybean crops require about half, 20–25 kg per hectare. [21] Yara International is the world's largest producer of nitrogen-based fertilizers. [22]
A number of countries have created their own national standards and certifying bodies for organic aquaculture. While there is not simply one international organic aquaculture standardization process, one of the largest certification organizations is the Global Trust, [9] which delivers assessments and certifications to match the highest quality organic aquaculture standards.
Adding urea to the ocean can cause phytoplankton blooms that serve as a food source for zooplankton and in turn feed for fish. This may increase fish catches. [ 54 ] However, if cyanobacteria and dinoflagellates dominate phytoplankton assemblages that are considered poor quality food for fish then the increase in fish quantity may not be large ...
On a dry-dry basis, 2–4 kg of wild-caught fish are needed to produce 1 kg of salmon. [23] The ratio may be reduced if non-fish sources are added. [20] Wild salmon require about 10 kg of forage fish to produce 1 kg of salmon, as part of the normal trophic level energy transfer. The difference between the two numbers is related to farmed salmon ...
Typical build ratios are .5 to 1 square foot of grow space for every 1 U.S. gal (3.8 L) of aquaculture water in the system. 1 U.S. gal (3.8 L) of water can support between .5 lb (0.23 kg) and 1 lb (0.45 kg) of fish stock depending on aeration and filtration.
Marine shrimp farming is an aquaculture business for the cultivation of marine shrimp or prawns [Note 1] for human consumption. Although traditional shrimp farming has been carried out in Asia for centuries, large-scale commercial shrimp farming began in the 1970s, and production grew steeply, particularly to match the market demands of the United States, Japan and Western Europe.