1, the demand of producing safe and high-quality horticultural products: soilless culture is the only cultivation method that can be completely controlled manually at present, and every step of production can be intelligently controlled to ensure that the products are safe and harmless and the quality is controllable. 2. Expansion of non-arable agricultural production: Soilless cultivation does not depend on the land where crops are produced, and only needs to use less substrate or water and fertilizer, and cooperate with greenhouse facilities and cultivation facilities to produce high-quality vegetables and flowers.

1. What is the practical significance of soilless culture technology?

1, it is necessary to produce safe and high-quality horticultural products.

(1) The expansion activities and living consumption of human beings have brought serious pollution to the atmospheric environment and cultivated land. At the same time, the unreasonable use of chemical fertilizers and pesticides in agriculture has also seriously affected the soil microecological balance, leading to the decline of soil quality. Animals, plants and insects living on land are facing survival challenges, such as unhealthy plant growth, aggravated pests and diseases, increased cost of prevention and control, unhealthy food, and increasingly hidden dangers of quality and safety.

(2) Soilless culture is the only cultivation method that can be completely controlled manually. From the selection of substrate and nutrient solution raw materials, the index requirements of irrigation water, to the scientific preparation of nutrition, standardized production technology and accurate cultivation control, every link of production can be intelligently controlled to ensure the safety and harmlessness of products and controllable quality.

2. The need to expand non-cultivated agricultural production.

Soilless culture can achieve high-yield cultivation of crops with less substrate or water and fertilizer, and can produce crops independently of land. Therefore, no matter whether it is Gobi desert or coastal beach, abandoned industrial and mining enterprises or landfill sites, as long as environmental improvement is carried out and the interference of these unfavorable factors is isolated, high-quality vegetables and flowers can be produced by taking advantage of its surface advantage of receiving natural sunlight and cooperating with greenhouse facilities, cultivation facilities, clean and pollution-free water and nutrient solution.

3. The needs of horticultural production and greening to expand the three-dimensional space of the city

With the development of modern urbanization, the blind development of construction real estate and the change of industrial age, more and more idle buildings will appear in large and medium-sized cities in the coming decades. How to use the indoor space of idle buildings and the facade and roof of high-rise buildings to expand urban green space, realize the functions of agricultural production and urban ecological adjustment, meet the supply of fresh food nearby, and beautify urban life is an inevitable trend of urban development in the future. Soilless culture will play an important role in the development of urbanization, three-dimensional greening and beautification, and high quality, safe and efficient production of vegetables and flowers.

4. Solve the obstacles of continuous cropping in protected cultivation.

(1) China is a big country in protected horticulture, and its protected cultivation area accounts for more than 80% of the world's total area. With the extension of greenhouse cultivation years, the obstacle of continuous cropping in greenhouse is becoming more and more serious, especially in the northern solar greenhouse. Continuous cropping and continuous cropping have become a major obstacle to high quality, high yield and high efficiency of vegetables, and the biggest crux of affecting vegetable safety.

(2) Greenhouse is a permanent agricultural facility, such as sunlight greenhouse and high-grade multi-span greenhouse, which can be used to produce horticultural crops for at least 15 years after completion, but the obstacle of continuous cropping in greenhouse is inevitable. The cost of greenhouse demolition and soil replacement is very high. How to realize the sustainable production of greenhouse, soilless culture is what people have to adopt. Replaceable? Mode of production. With the increasingly serious obstacle of continuous cropping in greenhouse, the problem of vegetable quality and safety is prominent, and vigorously popularizing soilless culture technology is the inevitable trend of the development of protected horticulture in China in the future.

5, the shortage of labor resources, the need for the development of factory farming.

(1) Since 2006, the phenomenon of labor shortage has generally started in all parts of China. It is not only difficult for factories and enterprises to recruit workers, but also the labor force engaged in agricultural production in rural areas is decreasing day by day. Rural left-behind women and the elderly have become the main force of agricultural labor, the quality of workers has generally declined, and the phenomenon of land and greenhouse abandonment has spread rapidly. Some enterprises or cooperative vegetable production enterprises can't recruit suitable labor. Even if there is, their wages and expenses are getting higher and higher, and the output of vegetable facilities on an acre of land is not enough to pay the wages of a labor force. Labor wage expenditure has become the main cost of agricultural production enterprises.

(2) Under the traditional facility environment, soil cultivation, sowing, fertilization and weeding are mainly manual operations, with poor production conditions, high labor intensity and more physical consumption. Most modern young people are unwilling to do this job, and the agricultural labor force is facing serious shortage and shortage. Without scientific supervision and policy guidance, food safety (quantity) and food safety (quality) will plague China's economic construction, social stability and national development.

Second, what are the ways of soilless culture?

1, submerged liquid flow culture

The nutrient solution layer is deep, and the roots of plants can extend in the deeper liquid layer. Each plant occupies a large amount of nutrient solution, and the concentration, dissolved oxygen, pH value, temperature and water storage of nutrient solution are not easy to change sharply, which provides a stable growth environment for plant roots.

2, nutrient solution film cultivation

In this method, plants are planted in shallow flowing nutrient solution. The nutrient solution layer of this method is shallow, and the root system of the plant is partly immersed in the nutrient solution and the other part is exposed to the water in the planting tank, which can better solve the aerobic problem of the root system of the plant.

3. Floating plate capillary culture

The method adopts the floating plate wet felt root separation technology of the cultivation bed, creates an oxygen-enriched environment to cultivate wet roots, and solves the contradiction between water and gas. A large amount of nutrient solution is stored in a long horizontal cultivation bed.