Freshwater nuclear pearl culture management technology: is the price of freshwater nuclear pearl expensive? Pearl, fresh water or sea water?

1 selection of pearl breeding water body

The water body of    pearl cultivation is at least more than 2000 centimeters, there is micro-running water, the water depth is more than 2m, and the water is too shallow. Pearl clam is easily affected by toxic substances such as hydrogen sulfide, ammonia and methane in the bottom layer. During the peak period of pearl growth from May to October, it is best to create slow flow conditions.

The water body of pearl cultivation should be selected to investigate the physicochemical and biological properties of the sediment. If the sediment contains a variety of anaerobic bacteria, a large number of poisons such as hydrogen sulfide, methane, amine and methylindole will be produced in the high temperature season. Before bead production, quicklime must be sprinkled on the sediment for improvement treatment.

   2 aquaculture water sports bead density

In order to determine the culture density of pearl mussel by   , the palatable feed biomass in cultured waters should be determined. The palatable algae and Chlamydomonas Lobomonass.p. Based on the study of the characteristics of culture and reproduction, the algal production potential of the bead-breeding water body was predicted, and the best bead-breeding density was determined.

Determination of the best pearl layer by    3

The physical, chemical and biological properties of each layer of    pearl water body are different, so the pearl clam must be cultured in the best pearl water layer. According to the relationship between algae biomass and transparency, the formula of the best pearl water layer can be obtained: the best pearl water layer (cm) two transparency (cm) x 0.8.

The aquaculture water layer of    pearl mussel is too shallow, and it is easy to produce thermal coma in high temperature season. The number of cyanobacteria in shallow water is the most in high temperature season, and its toxin affects the growth of pearl clam. Of course, the aquaculture water layer should not be too deep, otherwise the bait biomass is insufficient.

   4 supplements nutrient elements in pearl-rearing water

   (1) rare earth elements

The content of rare earth elements in the waters of    pearl cultivation is generally very low, because the existing state of rare earth elements in nature is mostly mineral character composition, or exists in the state of adsorption between mineral particles, so the soluble rare earth which is directly absorbed and utilized by pearl clam in water can not meet the normal needs of pearl clam. Therefore, the application of a small amount of soluble total element rare earth in the waters of Yuzhu can show obvious effect.

Although    rare earth elements are not nutrient elements needed in large quantities of shellfish, nor are they inherent components of pearls and shells, rare earth elements can act as "activators" in the physiological and biochemical processes of pearl secretion and deposition. When there is a lack of some elements necessary for pearlite deposition, such as Ca, Mg, Zn, Se and so on, some elements in rare earths can be substituted.

At the same time, among the rare earth elements, there are light-making elements and chromogenic elements of pearls, which play an important role in improving the quality traits such as pearl finish, refractive index and color saturation.

The experimental results of the authors of    show that the effect of rare earth on the secretion of pearl of Hyriopsis cumingii is mixed rare earth light rare earth and heavy rare earth. The suitable concentrations of mixed rare earths, light rare earths and heavy rare earths are 100g/m3, 100-300g/m3 and 100-150g/m3, respectively.

The physical and chemical properties of the soil under the water where    is developed from different soil parent materials are different, and the background values of rare earths in the water are also different. The content of rare earth in water increases with the increase of subsoil viscosity. In the water area of the bottom soil developed from the parent material of granite, the content of rare earth in the water body is high, and the concentration should be reduced when it is used, while in the water area with heavy sandy soil, the content of rare earth in the water body is generally low, so it is appropriate to increase its concentration.

Introduction of photosynthetic bacteria into    (2)

Among    photosynthetic bacteria (PSB), green sulfur bacteria, red sulfur bacteria and red non-hydrophobic bacteria are suitable for pearl clam breeding. Their bacteria not only have extremely high protein content (about 58% crude protein), but also have no inferior amino acid composition compared with yeast, soybean and egg white, so they are palatable food organisms with excellent quality. At the same time, PSB can effectively improve the main ecological factors (pH, DO, COD, ammonia nitrogen, etc.), especially the unique function of eliminating H2S which is produced by anaerobic decomposition of sediment under anoxic condition and highly toxic to pearl mussel.

   C02+2H2S → [CH2O] + H20+2S2

After the introduction of photosynthetic bacteria into the waters of    Yuzhu, no matter it is anaerobic and bright, or it is good and dark, it can reproduce well. Therefore, the PSB population is often in an advantageous position in the competition. Under the condition of anaerobic light, hydrogen or organic matter can be used as hydrogen donor, fixed carbonic acid and propagated, and organic compounds such as lower fatty acids can also be used as carbon source.

Is the price of freshwater nuclear pearls expensive? Generally speaking, it is possible for the market price to be more than 100 yuan, 200 yuan, 300 yuan, 400 yuan or more. Is pearl fresh water or sea water expensive? Sea water is more expensive than fresh water.