An organic fertilization system for sustaining soil health in plastic greenhouses

Plastic-greenhouse soils are estimated to be approx. 4 million ha. However, excessive use of inorganic fertilizers leads to severe soil degradation and environmental pollution. This review aims to propose an organic fertilization system using organic carbon sources to improve plant nutrient uptake. It reviewed literature on environmental constraints of plastic-greenhouse crops and the use of organic carbon sources on bio-stimulant production and soil toxin removal, and conducted an incubation experiment, an organic fertilization system design, and a field survey to verify the system. The organic fertilization system includes a basal application of organic amendments during the fallow period, in conjunction with the application of soluble carbon sources and/or bio-stimulants via fertigation during the plant production period. The organic carbon sources facilitate bio-stimulant production and accelerate soil toxin breakdown by harnessing in-situ soil microbial activity. The field survey demonstrated its effectiveness in promoting sustainable soil management. The organic fertilization system fully utilizes summer heat, fallow periods, and organic carbon sources to remediate soil constraints caused by excessive inorganic fertilization. Future studies should focus on screening effective carbon sources to produce bio-stimulants, and to degrade soil toxins in plastic greenhouses.