The self-pollution caused by mariculture

The self-pollution caused by mariculture is also one of the factors that cause red tide. Along with the development of the national coastal breeding industry, especially the vigorous development of the shrimp aquaculture industry, there is also a serious problem of self-pollution.

In the prawn culture, people give a large amount of feed and fresh bait. The increase of residual bait in the pool seriously pollutes the quality of aquaculture. On the other hand, a large number of sewage discharges into the sea, with a large amount of bait residue and faeces water containing ammonia, urea, uric acid, and other forms of nitrogen compounds, accelerating the eutrophication of seawater and providing suitable biological environment for the red tide organism to accelerate its proliferation, especially in high temperature, sultry, calm conditions when red tides happen most easily. Besides, natural factors are also important causes of red tides. What’s more, latitude location, season, ocean current and the degree of closure of sea area and some other natural factors can also have influence on them.

The destruction of Marine fisheries and aquatic resources are caused by red tide. Abnormal explosive proliferation of red tide organisms leads to the broken of Marine ecological balance. The relationship of food chain of Marine phytoplankton, zooplankton and benthic creatures, swimming creatures and interdependence and mutual restriction relationship become abnormal or broken, which will greatly undermined the main economic fish species of bait, destroyed the normal Marine food chain cycle, causing loss of fish, shrimp, crab, shellfish type feeding and sharp decline in fishery production.

The abnormal explosive propagation of red tide organisms can cause the lamella mechanical blockage of shrimps and shellfish, causing these creatures to suffocate and die. In the late period of red tides, large amounts of the red tide organisms die and in the role of bacterial decomposition, it can result in regional Marine environment seriously lacking oxygen or producing hydrogen sulfide and other harmful chemical substances, toxic, killing or anoxiating Marine creatures; In addition, some red tide creatures have biotoxins in their bodies or metabolites, which can directly poison fish, shrimp, shellfish and other organisms.