Utilization Status of Organic Fertilizer
Organic fertilizer is rich in organic nutrients such as organic matter, amino acids and proteins, and also contains inorganic nutrients such as nitrogen, phosphorus and potassium. It has always played an important role in the development of agriculture in China. Since the middle of the 20th century, due to the large-scale application of chemical fertilizers, people have paid insufficient attention to organic fertilizers, and the application area and application rate have gradually decreased, resulting in a decline in soil fertility and quality of agricultural products, and a decline in fertilization efficiency. With the development of the market economy and the increasing demand for green food, there is a higher demand for the quality of agricultural products. Therefore, the application of organic fertilizer has attracted wide attention. Because a large number of studies have shown that the application of organic fertilizer can not only improve crop yield, fertilize soil fertility, but also improve the quality of agricultural products, improve fertilizer utilization, save resources, and protect the ecological environment. It is an important way to achieve sustainable agricultural development.
1.Organic fertilizer type classification basis
Organic fertilizer is a general term for natural organic fertilizers that are locally sourced and collected locally in the countryside. Organic fertilizers are widely available in a wide variety of sources. Almost all materials that contain organic matter and provide a variety of nutrients can be called organic fertilizers. China is known for its traditional habit of accumulating and applying organic fertilizers, and a series of measures to make full use of various organic wastes for material and energy recycling in agricultural production.
In order to improve the validity of the survey data, the availability and comparability, and the national summary, on the basis of drawing on the achievements and practical experience of the predecessors, according to the organic fertilizer resources, characteristics and accumulation methods, the national organic fertilizer can be divided into: 10 categories of manure and urine, heap fertilizer, straw fertilizer, green manure, soil fertilizer, cake fertilizer, sea fertilizer, humic acid, agricultural town waste, biogas fertilizer, etc. Several varieties.
2.Organic fertilizer utilization status
2.1 Utilization of farmyard manure
One is a pile of manure. It is mainly used by farmers to use weeds, waste and crop straw in the high temperature season. The second is barnyard manure (excluding biogas residue, biogas slurry fertilizer). The third is biogas residue and biogas slurry. The main use of pigs, cattle, chickens and other livestock and poultry farming waste and farm waste as raw materials for biogas tanks, biogas is the main product, biogas residue, biogas slurry is a high-quality organic fertilizer. Biogas residue can be used as a base fertilizer or top dressing. The biogas slurry is used as a foliar fertilizer spray. Biogas fertilizer is a pollution-free organic fertilizer in agricultural production nowadays. It also treats pests and has obvious fertilizer effects, which is welcomed by farmers. The fourth is the soil and fertilizer. It is mainly used by farmers to clean the courtyard, clean the toilet, burn coal for cooking and heating, and use coal ash waste and municipal solid waste. After treatment, it can be used as fertilizer to promote the effective use of resources.
2.2 Crop straw utilization status
At present, the total amount of straw resources in China is 800.61 million tons. The main varieties are rice straw, wheat straw, corn stover, miscellaneous grain straw, potato straw, bean straw, cotton straw, rape straw and peanut straw. Among them, rice straw accounted for 25.6%, wheat straw accounted for 18.1%, corn straw accounted for 31.3%, 3 crop straw accounted for 75.0% of the total straw, and other crop straw accounted for 25%. At present, the main utilization methods of straw are direct returning to the field, dumping and returning to the field, returning the soil to the abdomen and serving as fuel. Most of the corn stalks are directly crushed and returned to the field, and a small part of them are silaged and returned to the fields. However, there is still a situation in which straw is incinerated; the bean straw portion is used as a fuel. Partially returning to the abdomen; sweet potato and peanut straw are mainly used as feed for returning to the field.
2.3 Farm waste utilization
There are two main aspects: one is to collect and use it back to the field; the other is to discharge into the environment, in which the excrement discharged into the environment consists of two parts, that is, piled up and discharged into the water body, because of the piled excrement and the discharge of human body water. The urine is not easy to separate, so the two are unified to be discharged into the environment. The excreta discharged into the environment is mainly cattle, poultry and pigs, accounting for 37%, 30% and 19% of the total phosphorus emissions to the environment, respectively.
2.4 Commercial organic fertilizer production
The production of commercial organic fertilizer is lagging behind. The number and output of organic fertilizer plants is small. There are also individual farmers who process and process some chicken manure. Prepared for use as a fertilizer. Commercial organic fertilizer is mainly used in the cultivation of vegetables and cash crops.