Application of sodium humate in aquaculture
Humic acid is a macromolecular organic substance widely found in nature. It is widely used in agriculture, forestry, animal husbandry, petroleum, chemical, building materials, medical and health, environmental protection and other fields, spanning dozens of industries. In particular, it now advocates ecological agriculture construction, pollution-free agricultural production, green food, pollution-free environmental protection products, etc., and makes humic acid highly respected. It turns out that human life and survival are inseparable from humic acid, and it is indeed a development. The promising sunrise industry belongs to a new type of special industry.
Humic acid contains complex macromolecular aromatics. The acid has a hydrophilic reversible colloidal property, which can be agglomerated and can be peptized. The internal surface area is large. The strong adsorption structure exists in the structure of the sulphuric acid, the oxidized reactive group and the ruthenium. The nitrogen-containing ring, such as noise extraction and pyrrole, has strong ion exchange performance and cationic coupling ability. The structure has a certain ability to reduce the wake-up and half-awake base. Therefore, these structures allow humic acid to function as ion exchange, chelation, adsorption, and peptization.
In recent years, with the rapid development of large-scale, intensive farms and aquaculture areas, the aquaculture environmental pollution problems have become more and more prominent. The high-density culture has made the excrement content of the over-fishing stocks in the water body. If the water is too high, the BOD and COD in the water body will be seriously exceeded. The fattening pond will cause eutrophication of the water body.
The indiscriminate use of chemical agents causes the ecological balance of the water body to be destroyed. The cross-infection between the water bodies has led to a more frequent abuse of drugs. There is a wide range of space for the application of sodium humate to remediate the polluted environment for various pollution problems.
First, improve water quality, fertilizer, water
The application of waterborne pesticides enriches various heavy metal ions in water. The humic acid extracted from weathered coal has a certain complexation with harmful heavy metal ions in wastewater, and the composite produced by the reaction of sodium humate with cellulose. The better complexation effect is expected to develop into an inexpensive heavy metal sewage treatment agent. The adsorption and desorption mechanism of sodium humate on bentazone was studied by adsorption kinetics, adsorption isotherm and IR, ESR techniques. Hydrogen bonding and charge transfer in the adsorption process of bentazone on sodium humate are also possible. The mechanism of existence. Polluted water contains a large amount of organic pollutants, which affects the eutrophication of water bodies. The main role of various biochemical indicators exceeding sodium humate is adsorption complexing to reduce the concentration of organic matter. If it contains microorganisms, humic acid will assist microorganisms. KIM et al. studied the effect of colloidal granules formed in water on the adsorption and mineralization of natural organic compounds. DJvacca et al. first published the promotion of humic acid on degrading bacteria. Its function is to adsorb complex phenanthrene and so on to improve the solubility of water-soluble organic substances, and concentrate it to the effective range of degrading functional microorganisms.
It promotes the cell transport of these compounds by microbial cells and promotes the role of electron transporters on the cell membrane. Although this mechanism is still unknown, it is known that humic acid has a certain influence on the existence and function of microorganisms. On the other hand, during heavy rain, the dissolved oxygen in the water of the pond is convected by the lower layer of the pool water, with less sunlight and poor photosynthesis, which easily leads to insufficient dissolved oxygen at the bottom of the pool. At the same time, the water temperature, pH value and salinity will also decrease.
However, if the dissolved oxygen in the aquaculture water is low, the organic matter at the bottom of the pond cannot be oxidatively decomposed normally, and more toxic substances such as ammonia nitrogen and nitrite are generated, which may cause damage to the cultured species and easily lead to disease occurrence. It has been verified that the addition of sodium humate in the fish pond is beneficial to adjust the H+ ion concentration and buffer the pH of the water (the pH of the freshwater aquaculture pond is generally controlled at 6.5-7.5, and the pH of the marine culture pond is maintained between 7.8 and 8.6). . Secondly, sodium humate can adsorb NH 3 and H 2 S in water and play a role in purifying the pool. Sodium humate reacts with various heavy metal ions to form an insoluble chelate compound, which reduces the toxicity of excessive water-soluble harmful metals to fish and shrimp, and ensures the relative balance of algae phase and bacterial phase.