Chrysanthemum Heart Gracilariaceae, Clam, And Purification Of Microbial Agents On The Shrimp Pond Environment Application Research

Dissolved inorganic nutrient (DIN) of the aquacultural environment is one of the main pollutions from aquaculture. In recent years, guided by the"Cleaner Production"and"Ecological culture", integrated culture pattern of shrimp and other species was paid great attention to. In the paper, different experiments in field enclosures such as: Gracilaria lichenoides and Fenneropenaeus chinensis polyculture, Scapharca subcrenata and Fenneropenaeus chinensis polyculture, Gracilaria lichenoides-Scapharca subcrenata and Fenneropenaeus chinensis polyculture were conducted. Through investigations on the variation of physi-chemical and biological factors and growth of the cultural species, the ecological effects of Gracilaria lichenoides and Scapharca subcrenata in the culture systems were discussed,The aim of this study is to find out measures to maintain a sustainable development of mariculture. The main results are following:1) This experiment was preliminary discussed environmental effects of Gracilaria.lichenoides on the water quality in shrimp cleaner production in enclosures. There were fifteen enclosures(5×5m)in respective which shrimp was cultured at density of 32ind·m^-2 and Gracilaria.lichenoides was cultured in different densities(120,240,360,480g·m^-2) in this experiment, in which were conducted five groups were treatments and three repetitions. After a period of ninety days cultured, the results showed Gracilaria. lichenoides have perfect effect on NH₄⁺-N and PO₄^3--P uptake rates 52.15% and 19.37% (P<0.05). So Gracilaria.lichenoides had a cleaner production effect on shrimp culture. The growth,survive rates and gross yields of shrimp with Gracilaria.lichenoides were better than control group(P<0.05). In different polytreatmeants, the optimum mixed densities of Gaillardia.lichenides was 360g·m^-2.2) There were fifteen enclosures(5×5m)in respective which shrimp was cultured at density of 32ind·m^-2 and Scapharca subcrenata was cultured in different densities (10,20,30,40g·m^-2) in this experiment, in which were conducted five groups were treatments and three repetitions. The results showed Scapharca subcrenata had a cleaner production effect on shrimp culture environment. In different polytreatmeants, the optimum mixed densities of Scapharca subcrenata was 30ind·m^-2.3) After the second experiment, Gracilaria.lichenoides was cultured in the optimum mixed densities(360g·m^-2) in this experiment. After a period of fifty days cultured again, the results showed the growth, survive rates and gross yields of shrimp in the treatments were better than control group(P<0.05). The results of water and sediment quality showed Gracilaria. lichenoides and Scapharca subcrenata could act as effective bio-filters in bioremediation for deteriorating environment. Functions it plays include assimilating large amount of dissolved organic and inorganic nutrients, releasing oxygen via photosynthesis, and establishing cleaner environment for shrimp culture in coastal hays and shallow seas.4) In the study of microbial products in purification control of aquaculture,...