Soilless cultivation refers to the method of planting plants without using natural soil, using or not using substrates, cultivating plant roots with nutrient solution or adopting other methods. Some scholars also define soilless cultivation, which is a technology in which natural soil is not used as a nutrient substrate in the process of crop cultivation, and crops are planted on a cultivation bed made of artificial substrate material without soil.
1. Traditional soilless cultivation
First of all, various inorganic fertilizers should be prepared into nutrient solutions, which not only ensure the balance between various elements, but also ensure that the growth needs of crops are met, with particular attention to the effectiveness of trace elements. Secondly, in the preparation process, various equipments are also required to be used together. The salts in the nutrient solution can pollute the environment when the water drains out of the system during irrigation.
2. Organic ecological soilless culture
Organic eco-type soilless cultivation refers to a cultivation technique that uses organic solid fertilizer and directly irrigates crops instead of irrigating crop roots with the culture medium used in traditional soilless cultivation. The organic ecotype can achieve fertilizer and water management through top dressing and fresh water irrigation. The organic substrate is the basis of plant nutrition, and the cost is lower than that of the nutrient solution prepared by inorganic fertilizers. Since the organic ecological soilless cultivation is irrigated with water, even if the liquid is discharged from the system, the pollution to the environment is smaller than that of the traditional soilless cultivation.
In the traditional organic ecological formula, peat, vermiculite, perlite, and peat are non-renewable resources, and excessive exploitation will destroy the wetland environment; vermiculite requires high calcination conditions, and all three are high-cost matrix materials.