Bio-fertilizer is also called microbial fertilizer. It is a kind of product that produces a specific fertilizer effect by the life activity of microorganisms and is a kind of fertilizer used in agricultural production. In recent years, some peasants and friends in the economic zone have indeed realized that fertilizers and fertilizers can be used fertilizers in practice and increase production. So what is the principle behind this? The current price of microbial fertilizer is indeed even higher than the price of organic fertilizer fertilizer, then! Why is it still used?
At present, the scope of application of microbial fertilizer covers basically all kinds of crops such as grain, vegetables, fruit trees, Chinese herbal medicine and tobacco. China's microbial fertilizer applications are mainly concentrated in the three major regions.
1 Southern rice planting area
The area of application reached 47 million mu in 2013, with an amount of more than 100,000 tons.
2 large and medium-sized cities around the area
The area is mostly the planting area of agricultural products with high economic value such as vegetables and fruits. The application of microbial fertilizer can improve the quality of agricultural products, reduce the occurrence of soil-borne diseases and increase the economic value of agricultural products.
3 Pearl River Delta, the Yangtze River Delta's contaminated farmland
Is exploring the application of microbial fertilizer to inhibit heavy metals, reduce pesticide consumption, protect the ecological environment of the technical methods and measures.
The evolution of soil environment
Since the 1970s and the 1980s, agricultural land in our country has been extensively using single chemical element fertilizers, such as large amounts of elemental fertilizers such as ammonium bicarbonate, thiamine, diamine and urea. Although these fertilizers can quickly absorb, increase production. However, this also caused the deterioration of the soil environment. Due to the large input of chemical fertilizers, a large amount of acid ions such as NO3- / SO42- / HPO4- accumulate gradually in the soil, causing the soil pH value to decrease gradually. The resulting soil hardness, compaction, the water will be flooding the land, clear days will be split. The deterioration of the soil environment has caused the following hazards:
1. Plant growth is slow, into sub-healthy state. Each plant has a suitable pH range, the vast majority of plant growth environment is slightly acidic and slightly alkaline environment. However, the presence of a large number of acid ions makes the plant roots can not normally absorb and secrete substances, resulting in root nutrition can not keep up. The root of the plant is the growth of the plant, his lack of nutrition has a direct impact on the growth of the entire plant. It even accelerated the weathering of primary and secondary aluminum-bearing minerals in the soil and released large amounts of aluminum ions, forming a formable aluminum compound that plants absorb. Long-term and excessive absorption of aluminum plants, will be poisoned, and even death.
2. Fertilizer utilization rate is low, big investment. After years of fertilizer inputs, soil minerals themselves have fixed a large amount of nutrients such as phosphorus and potassium to reach saturation. Re-fertilizers, then not only will not be adsorbed by the soil, but will be leaking along the water away, further causing the acidification of the soil environment. Soil acidification plant roots can not absorb the poor nutritional growth, farmers tend to increase fertilizer inputs, this will be more aggravate soil acid ion concentration, resulting in a vicious cycle.
3. Easy to breed bacteria, resulting in disease. Soil acidification will lead to some beneficial microbial flora reproductive capacity and decreased ability to live, and even death. On the contrary will make a number of harmful microorganisms took the opportunity to large-scale breeding, and then infected plant roots spread throughout the body. For example, the root rot of some crops is due to the invasion of harmful microorganisms.
Changes of rhizosphere microenvironment
The rhizosphere refers to the part of the soil that is affected by the root activity of the plant that is different in physical, chemical and biological properties from the soil. The range of the rhizosphere is small, generally means only millimeters away from the surface. Many rhizosphere chemical conditions and biochemical processes are different from soils. One of the most obvious is the rhizosphere pH, redox potential and changes in microbial activity. The distribution of nutrient concentration in rhizosphere soil solution is significantly different from soil.
Rhizosphere microorganisms are those that grow and multiply in the soil that is directly affected by the root system of the plant. Bacteria, actinomycetes, fungi and protozoa. They and plants are in an interdependent relationship that interacts with plant roots to promote each other. A large number of microorganisms gathered around the root system, the organic matter into inorganic substances for plants to provide effective nourishment; the same time, microbes can secrete vitamins, growth-stimulating hormone, and promote plant growth. During plant growth, dead root and root shedding (root hairs, epidermal cells, root crowns, etc.) and root and root excreted inorganic and organic substances are important sources of nutrients and energy sources for microorganisms.
Due to the interspersed root system, the rhizospheric aeration conditions and water conditions are better than the rhizosphere, thus forming an ecological environment conducive to microorganisms. The increase of acid ion concentration in the soil affects the physical and chemical changes of the root micro-ecological environment, resulting in the deterioration of the living environment of the microorganism and the ability of decomposing the organic matter and the secreted matter to decline, causing the root to be malnourished and affecting the growth of the plant
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