A new type of immobilized bacterial fertilizer, which was researched by Oil Crops Research Institute of Chinese Academy of Agricultural Sciences, was successfully developed not long ago and won the national invention patent. The immobilized bacterial fertilizer has the advantages of low production cost, long storage time and high effective bacteria number, which solves the production and storage problems of microbial bacterial fertilizer for spring harvest and summer sowing crops such as rape and wheat in China.
According to reports, the present invention uses sodium alginate as an embedding and fixing carrier to fix bacteria, activated carbon as an adsorption carrier and calcium dichloride as a fixing agent, and the combination of the three can adsorb a large number of bacterial cells and quickly dry them, so that living cells can be quickly dried and preserved, and are not easily influenced by microorganisms that pollute the environment. Fast-drying bacteria are dormant and can survive for a long time without exchanging substances with the outside world. Granular products have barrier function to protect bacteria from harmful environmental factors.
The Institute of Oil Crops, Chinese Academy of Agricultural Sciences, said nonsense that the invention solved five major problems in the production and application of microbial bacterial fertilizer in China at present, one is that the production and packaging are easy to pollute, the other is that the effective shelf life is short; Third, it is not easy to form a dominant community after bacteria fertilizer microorganisms enter the soil; Fourth, it is necessary to avoid agricultural measures such as pesticides and fertilizers, which are restricted by environmental factors when applied in the field; Fifth, it is difficult to produce and preserve bacterial manure in South China.
How to deal with the Pearl River Delta soil polluted by heavy metals? According to media reports, German scientists have recently developed a super-powerful bacterium that can eat toxic heavy metals. Yesterday (September 2), the reporter interviewed Chen Nengchang, a researcher of Guangdong Institute of Ecology and Soil, one of the soil remediation experts in the province, on the possibility and feasibility of "bacteria eating heavy metals" to repair soil. He pointed out that it is feasible in theory, but it faces problems such as how to separate and collect bacteria.
Found bacteria that can eat nuclear waste
According to the website of the American Physical Organization, German scientists have recently discovered a special kind of bacteria. It is said that this kind of bacteria can actually survive in toxic nuclear waste, and can also gather and adsorb toxic heavy metals. Foreign scientists believe that this bacterium has such strong adaptability that it may be used to clean up abandoned places containing toxic metals.
In this regard, Chen Nengchang told reporters that in theory, it is entirely possible for bacteria to eat heavy metals. "Eating" is actually an adsorption, that is, if microorganisms can survive in an environment with heavy metals, they will naturally adsorb heavy metals in the process of metabolism. According to reports, this method has developed well in Japan and Germany in the past few years.
However, it is understood that the research and experimental level of bacteria absorbing heavy metals in China is far less than that in foreign countries.
Soil remediation is still a big problem.
According to the investigation led by the State Environmental Protection Administration, the Pearl River Delta, the Yangtze River Delta and the Bohai Rim, where the economy developed first, are all facing serious soil pollution problems. Among them, 40% of farmland metal pollution in the Pearl River Delta exceeded the standard. The seriousness of heavy metal pollution has attracted the attention of a large number of experts.
Chen Nengchang is one of the experts. Recently, I did a soil remediation project in Dabaoshan, Wengyuan, Shaoguan. Dabaoshan is an area with serious heavy metal pollution caused by mining. Chen's method is to spread lime and silicon fertilizer in busy farming season to reduce the absorption rate of toxic heavy metals by crops. At the same time, they also plan to plant mustard, rape and other plants with better cadmium absorption function in the off-season this winter.
Chen pointed out that at present, in China, most experts are studying the remediation of soil contaminated by heavy metals by plant adsorption. Vetiveria zizanioides is one of them. Its root system is very developed, and the surface of the root can secrete chemicals to improve the activity of heavy metals, which can create an environment that is easy to absorb toxic substances in a local small environment. Therefore, it can be used to adsorb harmful substances such as heavy metals.
According to reports, the remediation of heavy metal pollution such as cadmium in this field has attracted many experts. For example, Sun Yat-sen University is studying Viola Baoshan, and Japanese experts are studying some ferns. As a kind of bioremediation, bacterial remediation is also considered as a promising method by many experts. However, some experts believe that these heavy metal-absorbing bacteria will become a serious problem if they are not easily separated and collected in the soil. Therefore, from the perspective of feasibility, the restoration and restoration of polluted farmland is still a considerable scientific problem.