In the spring of 1641, the Far Eastern Company's work in the Outer Northeast, Northeast, Korea, Japan, Jeju Island, Taiwan Island, Nanyang Islands, Luzon, Indochina, Ceylon, India, Indochina Peninsula, and Hetao was all at a standstill, and all of them were engaged in vigorous spring ploughing.

The situation in the Hetao area is special because the Hetao irrigation area has a gentle topography, poor underground runoff, saline soil and groundwater, arid climate, and strong evaporation. In this natural environment, due to the implementation of flood irrigation, there is irrigation but no drainage, especially in the late autumn to store water for irrigation, the water consumption increases, the groundwater level increases significantly, and freezes in the one-meter soil layer in winter.

Due to the freezing and the reduction of evaporation, there is an obvious temperature difference between the frozen layer of the soil and the unfrozen layer of the subsoil, which makes the groundwater continue to gasify and move from the subsoil to the frozen layer, gradually thickening the frozen layer of the soil, and increasing the water content of the frozen layer of the frozen layer. The saline-alkali is dissolved in water, which makes the one-meter soil layer in a state of salt storage, which becomes the internal factor of thawing and evaporating salt accumulation in spring. In spring, the frozen layer is digested, the evaporation is strong, and the salinity accumulates year by year, resulting in serious salinization of the soil.

Zhou Lin summed up the lessons and lessons of the Hetao irrigation area in history, and adopted measures to replace the Yellow River water with well water for water storage in the Hetao base area, and made the diving table buried to a depth of 2 to 2 meters in the early stage of freezing. Below 5 meters, it promotes the transition from the peak of groundwater level to the state of well irrigation, leaching and desalination in autumn and winter. At the same time, it changed the state of large water content and salt storage in the frozen layer in winter, and avoided the return of salt and salt accumulation in spring.

In addition, since last year, Zhou Lin has also taken the lead in implementing a large-scale grassland rotation method in the Hetao area, mainly with grain crops and high-quality pastures such as alfalfa or grass rhinoceros, as well as legume crops, which are regularly rotated in proportion.

According to the characteristics of various crops and the condition of the cultivated soil, a rotation period of two to three years is adopted. Depending on the stubble characteristics of various crops, different crops will be planned to be planted. Arrange them in a certain order and rotate the planting on the same plot.

Among them, alfalfa and grass rhinoceros are perennial grasses with strong nitrogen fixation capacity, and after two or three years of planting, the compacted or loose soil will change to a fertile aggregate structure.

Alfalfa and rhinoceros not only have a strong ability to fix nitrogen, but also have a high nutritional value. Moreover, the grass yield is high, and two or three crops can be harvested in a year. The company has been promoting forage planting in various places for several years and has achieved great results. Farmers in the Far East rotate their pastures, and the annual harvest of forage can also be sold to the company's forage processing plants.

Alfalfa grass is mixed with other crop straw to process into concentrate feed, which can not only replace a large amount of corn as feed, but also fertilize the field and improve the soil. It will not only promote the development of agricultural production, but also encourage every household in the base area to raise pigs, cattle, sheep, chickens, ducks, and rabbits, thereby promoting the great development of agricultural and animal husbandry production, and greatly improving the living standards of the peasants in the base areas.

Legume crops can fix nitrogen through symbiotic rhizobia, and the number of leaf litter is large, and the leaf litter is rich in nitrogen, so the nitrogen content in the soil is relatively rich. The nutritional value of beans is very high, and China's traditional diet pays attention to "grains should be nourished." If you lose beans, you are bad", which means that grains are nutritious. But without beans it will be out of balance.

Beans contain high protein content, good quality, and their nutritional value is close to animal protein, which is the best plant protein. For example, soybeans, peanuts and square beans are rich in protein and contain a lot of edible oils. The stems and leaves of beans are feed with high nutritional value and excellent green manure. Fresh pods, seeds, stems and leaves also contain several vitamins and are nutritious vegetables and green fodder for livestock.

Grassland rotation is conducive to the combination of agriculture and animal husbandry, and improves the production efficiency of agricultural systems. It is conducive to reducing soil erosion, making full use of light, heat, water and land resources, improving the productivity of farmland system, improving degraded soil, and improving farmland ecology. Remove toxic substances and reduce pests, diseases and weeds.

Cultivated land with a grass rotation method will yield a good harvest no matter what crops are grown. Especially in the Northwest Hetao, because of drought and lack of rainfall, it is necessary to rely on yellow irrigation, and the area of salinized land is bound to increase after many years, and the most effective way to improve these secondary salinized lands is to incorporate alfalfa and other excellent varieties into the planting system.

Zhou Lin has informed the company of the experience of land rotation in the Hetao base. The company attaches great importance to Zhou Lin's suggestion and decides to start farming in the Northeast and Outer Northeast regions from this year.

At present, the company has begun to adjust the cultivated land of farmers in eastern Liaoning, Northeast China and Outer Northeast China, mainly planting crops, from the previous main planting of single corn, sweet potatoes and potatoes, to peanuts, soybeans, wheat, rice, sugar beet, sunflower, cotton, as well as a variety of high-quality grasses and leguminous forages and other crops.

After in-depth investigation and research, the Ministry of Agriculture and Forestry of the company screened the types of main crops and attached crops according to the production conditions and natural conditions of agriculture and animal husbandry in various places, determined the crop rotation combination and crop rotation method, divided the crop rotation division, made the crop rotation periodic table, and prepared the crop rotation plan, and scientifically carried out the field and grass rotation mechanism.

In the future, the company's agriculture and forestry department will also promote the cultivation method of grassland rotation on all cultivated land in the Far East-controlled area. For example, the three-year rotation of soybean-forage-corn combination with one cropping in the northern region, and the multi-cropping rotation of green manure crop-rice-rape-rice-wheat-rice-rice under the condition of multi-cropping in the south under the condition of multiple cropping. In addition, there are cereal rotation, bean rotation, grain and cash crop rotation, water and drought rotation and other crop rotation methods.

Crop rotation is a green, low-cost agricultural measure. Compared with chemical fertilizers and pesticides, the grassland rotation mechanism can regulate soil fertility, improve farmland ecology, and reduce diseases, insects and weeds, and some functions cannot be replaced by chemical fertilizers and pesticides. However, grassland rotation is one of the best strategies to improve soil fertility and increase grain production.

In modern China's agriculture, under the influence of various conditions such as less land and more people, large demand for food crops and the needs of the market economy, the problem of soil degradation is serious. These include soil erosion, desertification, soil salinization, soil depletion and soil pollution. In fact, the grassland rotation mechanism is a good solution, but China's national conditions and agricultural resource conditions make it difficult to implement a large-scale grassland rotation mechanism in various regions.

At present, most of the company's Hetao, Liaodong, Northeast and Outer Northeast are vast and sparsely populated, and most of the land is newly cultivated, and all kinds of conditions are met for the implementation of the grassland rotation mechanism.

The company's agriculture and forestry department can make full use of scientific planting technology, excellent seeds, sufficient chemical fertilizers and soil fertilizers, and scientific grassland rotation mechanism to carry out scientific and reasonable combination, change the planting habits of wide planting and thin harvest in this era, and achieve grass water storage, grass soil conservation, grass animal husbandry, grass to promote agriculture, in one fell swoop. In the end, we will achieve good results and gratifying results in improving soil and fertilizing fields and increasing grain production. (To be continued.) )