Study on aquaculture capacity of offshore cage aquaculture based on dissolved oxygen dimension analysis model

ZHANG Jing; TANG Baogui

doi:10.13984/j.cnki.cn37-1141.2025.01.005

Abstract：The concentration of nutrients such as nitrogen and phosphorus in water,sulfide content in sediment and dissolved oxygen content in water may be the limiting factors for aquaculture capacity in baiting type offshore cage aquaculture.However,studies on nitrogen,phosphorus,sulfide content in sediment and other limiting factors are all based on the perspective of meeting environmental standards.From the perspective of aquaculture itself,the content of dissolved oxygen is often the key factor to control aquaculture density and limit aquaculture capacity.For this purpose,A dimension analysis model of dissolved oxygen was established and the aquaculture capacity of Trachinotus ovatus was cal-culated as an example in Houshui bay offshore cage aquaculture in this paper.The results showed that the theoretical cage culture capacity of Trachinotus ovatus was about 22500 tons.Compared with the existing fish production,it can be seen that the aquaculture capacity has reached saturation in Houshui bay offshore cage aquaculture.According to the results of the aquaculture capacity and the proportion of current cage culture specifications,the estimated number of cages with a circumference of 40 m and 60 m were about 2127 and 435,respectively,and the total number was about 2562 which could be judged that the number of cage culture in Houshui bay has also reached saturation,and it was not suit-able to be further developed.Due to the limitations of each method,the aquaculture capacity should not be exceeded in practice,and the number of cage culture could be comprehensively considered according to the calculation results of the two methods.The development trend was to eliminat cages with 40 m circumference year by year and developed large-scale cages,which could not only reduced the number of cage culture,but also reasonably adjusted the density of single cage according to the aquaculture capaci-ty,so as to obtain the maximum economic and environmental benefits.