[Environmental safety assessment on the new super absorbent polymers applied into a soil-Chinese cabbage system]

Super absorbent polymers (SAPs), a new water retention material, have a potential for application in water-saving agricultural production. In this study, we investigated the effects of SAPs, synthesized from natural plant extracts, on Chinese cabbage fresh weight, soil water content, soil water stable aggregates, soil microbial biomass (carbon) and soil microbial respiration under three water conditions (excessive, normal and deficient) and two SAPs application strategies (bulk treatment and spraying treatment). The results showed that the SAPs significantly promoted the soil water content, water-stable aggregates (> 0.25 mm) and the soil microbial activities, especially under the water deficient conditions. Meanwhile, SAP application strategy was of great significance to the effects on Chinese cabbage and soil properties. Compared with the control treatment under normal water condition, spraying treatment of Jaguar C (S-JC) could reduce irrigation water amount by about 25% without reducing the crop production. Furthermore, compared with the control treatment under the same water condition with S-JC (deficient), it could increase Chinese cabbage production by 287%. Thus, SAPs is an environmental friendly water-saving technique in agricultural production.