Effects of different water and fertilizer treatments on the matrix properties and plant growth of tailings waste

Abstract

Phytoremediation is widely regarded as the most environmentally sustainable green technology for remediating mineral waste. The appropriate ratio of amendments can improve the substrate environment for plant growth and improve the repair efficiency. Study its improvement effect on tailings wasteland from the aspects of plant growth and nutritional elements. Considering that, this study explored the effects of water and fertilizer treatment on the physical and chemical properties and plant growth of quarry waste matrix with different ratios. The original soilwithout fertilizer and 45% water treatment was used as the control group (CK), and and the composite soil with different ratios of original soil and slag and various water and nitrogen fertilizer treatment combinations was used as the experimental group. Pennisetum alopecuroides (L.) Spreng, Campsis grandiflora (Thunb.) Schum, Setaria glauca (L.) Beauv, Periploca sepium Bunge and mugwort (Artemisia argyi Levl. Et Vant.)were planted in the control group and the experimental group respectively. After 30 days of nitrogen fertilizer and water treatment, an analysis was conducted to assess the physicochemical properties and the plant growth status of the tailing matrix for each experimental treatment. The results showed that the M5 treatment fostered the growth of Pennisetum alopecuroides (L.) Spreng and mugwort, while the M2 treatment promoted the growth of Campsis grandiflora (Thunb.) Schum, and the M3 treatment was beneficial to the growth of Setaria glauca (L.) Beauv and Periploca sepium Bunge. The soil matrix pH of Pennisetum alopecuroides (L.) Spreng, Campsis grandiflora (Thunb.) Schum, setaria glauca (L.) Beauv, and Periploca sepium Bunge and mugwort are all greater than 7.5, and macronutrient elements such as TK, AK, TN, AN, TP, and AP all have certain levels of improvement. PCA analysis showed that there were significant differences in substrate properties and plant growth properties between treatments for Pennisetum alopecuroides (L.) Spreng, Campsis grandiflora (Thunb.) Schum, Setaria glauca (L.) Beauv, Periploca sepium Bunge and mugwort (P<0.05). Correlation network and structural equation analysis showed that the water and fertilizer10 matrix had a significant positive correlation with soil AN and TN (P<0.05), and TK had a positive correlation with the growth status of five plants. The water and fertilizer substrate has a positive correlation with the growth status of Pennisetum alopecuroides (L.) Spreng, Setaria glauca (L.) Beauv, Periploca sepium Bunge and mugwort, and a negative correlation with the growth status of Campsis grandiflora (Thunb.) Schum.