Decapitation and root pruning, can impact plant morphological and physiological characteristics, which may determine the efficiency of phytoremediation. However, the effects of decapitated and root-pruned plants on the characterization of dissolved organic matter (DOM) and enzymatic activity, which determine the bioavailability of soil pollutants, have rarely been reported. This study aims to characterize DOM and enzymatic activity in the rhizosphere soil of Sedum alfredii when treated by decapitation and root pruning. Decapitation, slight pruning (10% root cutting), and their combination stimulated S. alfredii to secrete more DOM in the rhizosphere soil compared with the control. Furthermore, the proportions of hydrophilic increased from 42.7% in the control to 57.1% in the decapitation and slight pruning combination. Soil urease, invertase, and neutral phosphatase activities were higher in the rhizosphere soil of decapitated and root-pruned S. alfredii, and the highest values were observed with their combination. DOM from the soils of decapitated and root-pruned S. alfredii had significantly higher Cd extraction ability compared with that of the untreated species. Based on the findings of this study, we suggest that decapitation and root pruning can improve the phytoremediation efficiency of S. alfredii by increasing the bioavailability of Cd in its rhizosphere.

断头和根修剪会影响植物的形态和生理特性，这可能决定植物修复的效率。然而，很少有人报道断头和修剪过的植物对溶解性有机物（DOM）和酶活性（决定土壤污染物的生物利用度）表征的影响。这项研究旨在表征断头和根修剪处理后景天草根际土壤中的DOM和酶活性。断头，轻度修剪（砍伐根的10％）及其组合刺激了S. alfredii与对照相比，在根际土壤中分泌更多的DOM。此外，亲水性的比例从对照组的42.7％增加到断头和轻微修剪组合的57.1％。断头和根修剪的S. alfredii的根际土壤中的脲酶，转化酶和中性磷酸酶活性较高，与它们的组合最高。与未经处理的物种相比，去头和根修剪的苜蓿链球菌土壤中的DOM具有更高的Cd提取能力。基于这项研究的结果，我们建议断头和根修剪可以通过增加Cd在其根际中的生物利用度来提高S. alfredii的植物修复效率。