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The C. farreri China's major marine aquaculture shellfish one With the growing scale of the development of shellfish farming, aquaculture environmental degradation, increased disease, the reason is obviously closely related to pollution and scallop culture. Shellfish excretion of the main factors affecting the water quality of the breeding waters, nitrogen, phosphorus scallops excrement greater impact on the two elements of water, so the form of the scallop excretion of nitrogen and phosphorus analysis, excretion rate and particle Study of the degradation rate of the nitrogen, phosphorus discharges is very necessary. Scallops nitrogen and phosphorus excretion mainly exists in two forms, ie mainly by the the urination process of the formation of dissolved nitrogen, phosphorus and by the the defecation process of the formation of particulate nitrogen and phosphorus. Experimental deposition biological half-site water the scallop waste nitrogen, phosphorus forms and the form of excreta excretion rate were determined. At the same time, to take the simulated experiment and measured particulate excretion rate of degradation of the organic nitrogen and phosphorus. And explored under the experimental conditions, temperature, shell length and bait density of environmental factors on nitrogen excretion, the establishment of the mathematical model, and the threshold condition is false fecal estimated. The results show that within the range of experimental conditions, the scallop excreta Nd The NP distribution range: 2.12 ± 1.21μg/h/ind, 0.78 ± 0.63μg/h/ind, Pd, PP, and the distribution ranges were: 0.41 ± 0.33μg/h/ind, 0.17 ± 0.15μg/h/ind. Nd, Np total percentage of nitrogen excretion were 72.9%, 27.1%, which ammonia nitrogen accounted for 49.6%, Pd, Pp total phosphorus excretion percentage was 70.4%, 29.6%, respectively. Various forms of N, P excretion rate increased with increasing temperature. Experimental set temperature and chlorophyll a concentration range have false manure generated fake feces and the true fecal excretion chlorophyll a concentrations positively correlated, and the chlorophyll a concentration of more than 54.07 ± 6.92ug / L when false The increase in fecal excretion was significantly higher than the true dung. In the experimental temperature, the scallops particulate excretion of total nitrogen, total phosphorus degradation rate: 0.235mg the · d -1 , 0.061mg \u0026 d -1 . Was dissolved in water COD degradation rate constant k ranges from 0.066 to 0.012, with an average of 0.09. In the experimental temperature range (9.2 to 27.3 ° C) Nd and Np with the increase in temperature and shell length (or weight) showed a tendency to increase deceleration, it is the relationship between temperature and shell length can be quantified with a logarithmic curve
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