Study On The Effects Of Jellfish (Rhopilema Esculenta Kishinouye) Farming On The Environment Of The Culture Ponds

Rhopilema esculenta Kishinouye belongs to Coelentera, Scyphozoa, Rhizostomeae, Rhizostomatidae, Rhopilema. Jellyfish has become a popular industry of aquaculture industry because of its fast growth, low cost of production, huge market, high economic benefit and small risk, etc. In the process of jellyfish high-density culture, the physiological and procreative activities including the excretion and feeding of jellyfish result in a series of problems to the ecological environment. Though research on the effects of sea-water aquculture on culture to the environment has been done in other types, litter related research has been reported in jellyfish as the research on jellyfish has just been done.This experiment was carried out in the farming ponds of jellyfish in JingHai Bay between April 2010 and November 2010.Using BACI experimental design, by comparing the indicators of aquatic water, sediment and seston (including DO,NH₄-N,NO₃-N,Chl a,SR and TOM) between culture pond and non-culture pond during this time, the effect of jellyfish culture to the culture environment can be studied.The main results are summarized as follows:①In July 2010, when the jellyfish were intensively cultured. The DO content of the bottom aquatic water in culture areas was significantly higher than in non-culture areas, while the difference of the DO content of surface and middle-level aquatic water between the culture areas and the non-culture areas was not significant. The Chl a content of the surface and middle-level aquatic water was significantly higher than that in the non-culture areas, while the Chl a content of bottom aquatic water in culture areas was significantly lower than that in non-culture areas. The NH₄-N content of each aqutic water layer in the culture areas was significantly higher than that in the non-culture. The NO₃-N content of the middle-level aqutic water in the culture areas was significantly lower than that in the non-culture, while its content of the bottom aquatic water in the culture areas was significantly higher than that in the non-culture areas.②During the jellyfish culture, both the NH₄-N and NO₃-N content of the sediment in the culture areas were significantly higher than those in the non-culture, while the Chl a and TOM content of the sediment in culture areas were significantly lower than those in the non-culture areas.③During the experiment, both the SR and NH₄-N content of the seston in culture areas were significantly higher than those in the non-culture, while the Chl a and TOM content of the seston in non-culture areas were significantly higher than those in the culture areas.