What are the methods and precautions of returning straw to the field?
(1) Straw is crushed and returned to the field.
The form of straw returning to the field is that the harvested straw is mechanically crushed, cultivated and directly pressed into the soil. This can fully retain the nutrients of straw in the soil, but there are also some shortcomings, mainly as follows:
① Due to the excessive or uneven amount of straw returning to the field, the contradiction between soil microorganisms (that is, microorganisms transformed from straw) and crop seedlings on nutrients is easy to occur, and even the phenomenon of yellow seedlings, dead seedlings and yield reduction occurs. Therefore, under normal circumstances, the straw per mu should not exceed 300 kg, nor should it exceed 500 kg, otherwise it will affect the decomposition speed of straw in soil and crop yield. Therefore, when straw is directly returned to the field, some nitrogen fertilizer and some phosphorus fertilizer should be applied appropriately to supplement phosphorus deficiency.
(2) After the straw is ploughed and returned to the field, the soil becomes too loose, the proportion of pore size is uneven, and there are too many macropores, which leads to wind running, and the soil and seeds can not be in close contact, which affects the germination and growth of seeds, makes the root system of wheat unstable, and even leads to hanging roots. The measures we should take are timely irrigation or rolling, so that the soil is in close contact with the seeds and can germinate normally. Or improve the grinding fineness, preferably below 3.5 cm.
③ It is prone to diseases and insect pests. Some pests and diseases such as eggs and bacteria in straw can't be killed in the process of direct crushing of straw, but remain in the soil after returning to the field, and the pests and diseases occur directly or in the next winter. Therefore, effective measures should be taken to deal with it.
(2) Straw mulching and returning to the field
In this way, the straw is crushed and directly covered on the ground. This can reduce the evaporation of soil moisture, achieve the purpose of moisture conservation, and increase after decay.
Soil organic matter. But this will bring inconvenience to irrigation, waste water resources and seriously affect sowing. This form is suitable for mechanization on demand and also suitable for arid areas.
(3) Returning compost to the field
Composting is to fully decompose crop straw at high temperature and then apply it to the soil. Some composting methods are through livestock pens, and some are carried out by adding biological bacteria and water. This is beneficial to the absorption of plants. However, in the process of straw decomposition, a certain amount of nitrogen is lost, which is labor-consuming, time-consuming and occupies land, so it is rarely used by ordinary farmers now.
(4) burning and returning to the field
After burning straw, the effective components become waste gas and are discharged into the air, which wastes a lot of energy. The remaining potassium, calcium, inorganic salts and trace elements can be used by plants to kill eggs, pathogens and grass seeds during combustion. However, incineration has caused waste of resources, environmental pollution and ecological damage, and at the same time affected traffic and people's lives, becoming a major public hazard. We must resolutely take measures to ban burning.
(5) Returning to the field via abdomen
In this form, straw is used as feed, some nutrients, such as sugar, protein, cellulose, etc., are digested and absorbed in the abdomen of animals, and the rest are converted into feces, which are applied to the soil to improve soil fertility. However, the nutrients absorbed by animals are effectively converted into meat, milk and so on. , for human consumption, improve the utilization rate. This method is the most scientific and ecological, and should be advocated and popularized.
(6) Returning stubble to field
That is, when harvesting rice, leave the rice stubble above 10 cm and turn it over.
Soil can also play the role of returning straw to the field. When ploughing high stubble land, it should be ploughed over 15 cm, thoroughly turn the stubble into deep soil, and carefully rake the ground to prevent the stubble from floating on the water and affecting the rice transplanting operation. If the rice stubble is not thoroughly turned, it can be pressed under the field with a rolling rake. The advantages of high stubble can not only play the role of returning straw to the field, but also have the advantages of simple method, labor saving, reducing the haulage of straw back and forth and low cost.
Returning straw to field has many advantages, but it also has disadvantages. Whether or not to return the straw to the field and how to return it to the field should be determined according to the actual situation of the local area, the household and the plot, and it must not be across the board. In addition, if the local animal husbandry is developed and forage grass is scarce, it is not appropriate to promote the implementation of straw returning measures, because straw is a good feed for livestock, and feeding livestock with straw can greatly reduce the feed cost, make livestock survive the winter safely and promote the development of animal husbandry. Pay attention to the following items when returning to the site:
Control the amount of straw directly returned to the field: the amount of straw directly returned to the field is generally dry straw 100 kg ~ 150 kg or wet straw 350 kg ~ 500 kg per mu.
When chemical weeding is carried out, the effective dosage should be appropriately increased: the direct return of straw to the field correspondingly accelerates the degradation speed of herbicides in soil and shortens the residue period of pesticides. Therefore, the effective dosage should be appropriately increased when chemical weeding is carried out.
Appropriate replenishment of soil moisture: Adequate moisture is an important condition to ensure microbial decomposition of straw. After returning the straw to the field, the soil is looser and the water demand is greater. Therefore, it is necessary to ensure that there is enough water in the rice field to facilitate the full decomposition of straw.
Scientifically increase the application of nitrogen fertilizer: the carbon-nitrogen ratio of rice straw is 75∶ 1, while the carbon-nitrogen ratio required by soil microorganisms to decompose organic matter is 25∶ 1. It shows that a large amount of nitrogen fertilizer needs to be supplemented after rice straw is directly returned to the field. Otherwise, the straw decomposed by microorganisms will compete with crops for nitrogen and water in the soil, which is not conducive to the normal growth of crops. Therefore, the application amount of nitrogen fertilizer should be increased as soon as possible after returning straw to the field to ensure the effect of returning straw to the field.
1. What is the present situation of peanut production in Liaoning Province?
Peanut is the main oil crop and cash crop in Liaoning Province. In recent years, it is the third largest crop in Liaoning Province after corn and rice. Liaoning province belongs to arid and semi-arid areas, and there are many medium and low yield fields, especially in the sandy land in northwest Liaoning and the hillside in south Liaoning. Peanut is a drought-tolerant, barren-tolerant and stable crop, which is suitable for planting in sandy land. Moreover, the autumn temperature is high, the sunshine is good, and there are few rainy days, which is suitable for drying peanuts, and the produced peanuts are less polluted by Aspergillus flavus. The development of peanut industry will play an important role in promoting the rational distribution of crops in Liaoning province, making full use of natural resources such as land and light, improving productivity per unit area, increasing planting benefits and farmers' income. The arable land suitable for peanut planting in Liaoning Province is about 6.5438+million mu, mainly distributed in Fuxin, Jinzhou, Tieling, Shenyang, Huludao, Anshan and Dalian. In 20 13, the peanut planting area in Liaoning was 447,000 hectares, and the total annual output was about 445,000 tons. About 70% of peanuts are exported, accounting for about 20% of the country.
In 20 13, the peanut planting area in Fuxin city was 2,787,600 mu, and the output reached 608,000 tons, ranking as 1, with an average yield of 2 18 kg per mu. The planting area of peanuts in Tieling City is 8 1.75 million mu, and the output reaches 20 1. 1 10,000 tons, ranking second, with an average mu.
The output is 246 kg; The peanut planting area in Shenyang is 607,800 mu, and the output reaches/kloc-0.40 million tons, ranking third, with an average yield of 230 kg per mu. The peanut planting area in Jinzhou is 580,500 mu, and the output reaches 2 1.22 million tons, ranking fourth, with an average yield per mu 1.93 kg. The peanut planting area in Huludao City is 335,900 mu, and the output reaches 48,000 tons, ranking fifth, with an average yield per mu 143 kg. The peanut planting area in Dalian is 86,700 mu, and the output reaches 1.73 million tons, ranking sixth, with an average yield of 200 kg per mu. The peanut planting area in Anshan City is 80,900 mu, and the output reaches 1.54 tons, ranking seventh, with an average yield per mu of 1.9 1 kg. The total peanut planting area in other cities is 97,500 mu, and the output reaches 23,300 tons.