Tolerance and enrichment characteristics of Jasminum nudiflorum under copper treatment from soil and atmosphere

As one of the common garden shrub species in Beijing, Jasminum nudiflorum is very popular among citizens for its unique ornamental properties in early spring. Copper (Cu) pollution is one of the most serious heavy metal pollution types in Beijing. To explore the remediation effect of J. nudiflorum on urban copper pollution. By simulating the soil and atmospheric copper pollution conditions in Beijing, pot experiments were conducted to set up nine different concentrations of soil and atmosphere Cu treatments to verify the Cu enrichment ability and physiological growth characteristics of J. nudiflorum. The results were as follows: (1) Soil treatment and atmospheric deposition treatment and were able to significantly increase Cu content in root, stem and leaf of J. nudiflorum, among them, the contribution of soil ranged from 63.48% to 96.99%. The Cu content in each treatment showed the order of root>stem>leaf. (2) Under atmospheric treatment, photochemical conversion efficiency (Fv/Fm) and relative chlorophyll content (SPAD value) were increased, initial fluorescence (F0) was decreased, and photosynthetic capacity was promoted. The photosynthesis of J. nudiflorum was inhibited by soil treatment and co-treatment with soil and atmosphere. (3) Compared with atmospheric single factor treatment, soil single factor treatment and co-treatment with soil and atmosphere resulted in increased accumulation of reactive oxygen species (ROS), increased membrane lipid peroxidation, increased malondialdehyde (MDA) content, and decreased antioxidant enzyme activity and proline (PRO) content, and finally led to damage of the biofilm system. (4) The low-concentration Cu treatment promoted the growth of J. nudiflorum, while the high-concentration copper treatments (SHAL, SHAH) inhibited the growth of J. nudiflorum. The minimum value of the root tolerance index (TI) of J. nudiflorum was 69.19%, which indicated that J. nudiflorum belonged to a highly tolerant plant. In conclusion, under the simulated treatment of soil and atmosphere Cu pollution in Beijing, J. nudiflorum can effectively absorb and enrich Cu in soil and atmosphere while maintaining its own normal physiological and growth activities. This conclusion provides a certain theoretical basis for the prevention and control of Cu pollution and the maintenance and restoration of the ecological environment in Beijing.